[FFmpeg-devel,PATCHv12] libavcodec: v4l2: add support for v4l2 mem2mem codecs

Submitted by Jorge Ramirez-Ortiz on Sept. 11, 2017, 2:26 p.m.

Details

Message ID 1505139993-3789-2-git-send-email-jorge.ramirez-ortiz@linaro.org
State New
Headers show

Commit Message

Jorge Ramirez-Ortiz Sept. 11, 2017, 2:26 p.m.
This patchset enhances Alexis Ballier's original patch and validates
    it using Qualcomm's Venus hardware (driver recently landed upstream
    [1]).

    This has been tested on Qualcomm's DragonBoard 410c and 820c
    Configure/make scripts have been validated on Ubuntu 10.04 and
    16.04.

    Tested decoders:
           - h264
           - h263
           - mpeg4
           - vp8
           - vp9
           - hevc

    Tested encoders:
           - h264
           - h263
           - mpeg4

    Tested transcoding (concurrent encoding/decoding)

    Some of the changes introduced:
        - v4l2: code cleanup and abstractions added
        - v4l2: follow the new encode/decode api.
        - v4l2: fix display size for NV12 output pool.
        - v4l2: handle EOS.
        - v4l2: vp8 and mpeg4 decoding and encoding.
        - v4l2: hevc and vp9 support.
        - v4l2: generate EOF on dequeue errors.
        - v4l2: h264_mp4toannexb filtering.
        - v4l2: fixed make install and fate issues.
        - v4l2: codecs enabled/disabled depending on pixfmt defined
        - v4l2: pass timebase/framerate to the context
        - v4l2: runtime decoder reconfiguration.
        - v4l2: add more frame information
        - v4l2: free hardware resources on last reference being released
        - v4l2: encoding: disable b-frames for upstreaming (patch required)

    [1] https://lwn.net/Articles/697956/

    Reviewed-by: Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
    Reviewed-by: Alexis Ballier <aballier@gentoo.org>
    Tested-by: Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
---
 Changelog                 |   1 +
 configure                 |  28 ++
 libavcodec/Makefile       |  15 ++
 libavcodec/allcodecs.c    |   9 +
 libavcodec/v4l2_buffers.c | 448 ++++++++++++++++++++++++++++++++
 libavcodec/v4l2_buffers.h | 121 +++++++++
 libavcodec/v4l2_context.c | 638 ++++++++++++++++++++++++++++++++++++++++++++++
 libavcodec/v4l2_context.h | 208 +++++++++++++++
 libavcodec/v4l2_fmt.c     | 182 +++++++++++++
 libavcodec/v4l2_fmt.h     |  34 +++
 libavcodec/v4l2_m2m.c     | 332 ++++++++++++++++++++++++
 libavcodec/v4l2_m2m.h     |  94 +++++++
 libavcodec/v4l2_m2m_dec.c | 226 ++++++++++++++++
 libavcodec/v4l2_m2m_enc.c | 350 +++++++++++++++++++++++++
 14 files changed, 2686 insertions(+)
 create mode 100644 libavcodec/v4l2_buffers.c
 create mode 100644 libavcodec/v4l2_buffers.h
 create mode 100644 libavcodec/v4l2_context.c
 create mode 100644 libavcodec/v4l2_context.h
 create mode 100644 libavcodec/v4l2_fmt.c
 create mode 100644 libavcodec/v4l2_fmt.h
 create mode 100644 libavcodec/v4l2_m2m.c
 create mode 100644 libavcodec/v4l2_m2m.h
 create mode 100644 libavcodec/v4l2_m2m_dec.c
 create mode 100644 libavcodec/v4l2_m2m_enc.c

Comments

wm4 Sept. 19, 2017, 7:35 p.m.
On Mon, 11 Sep 2017 16:26:33 +0200
Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> wrote:

>     This patchset enhances Alexis Ballier's original patch and validates
>     it using Qualcomm's Venus hardware (driver recently landed upstream
>     [1]).
> 
>     This has been tested on Qualcomm's DragonBoard 410c and 820c
>     Configure/make scripts have been validated on Ubuntu 10.04 and
>     16.04.
> 
>     Tested decoders:
>            - h264
>            - h263
>            - mpeg4
>            - vp8
>            - vp9
>            - hevc
> 
>     Tested encoders:
>            - h264
>            - h263
>            - mpeg4
> 
>     Tested transcoding (concurrent encoding/decoding)
> 
>     Some of the changes introduced:
>         - v4l2: code cleanup and abstractions added
>         - v4l2: follow the new encode/decode api.
>         - v4l2: fix display size for NV12 output pool.
>         - v4l2: handle EOS.
>         - v4l2: vp8 and mpeg4 decoding and encoding.
>         - v4l2: hevc and vp9 support.
>         - v4l2: generate EOF on dequeue errors.
>         - v4l2: h264_mp4toannexb filtering.
>         - v4l2: fixed make install and fate issues.
>         - v4l2: codecs enabled/disabled depending on pixfmt defined
>         - v4l2: pass timebase/framerate to the context
>         - v4l2: runtime decoder reconfiguration.
>         - v4l2: add more frame information
>         - v4l2: free hardware resources on last reference being released
>         - v4l2: encoding: disable b-frames for upstreaming (patch required)
> 
>     [1] https://lwn.net/Articles/697956/
> 
>     Reviewed-by: Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
>     Reviewed-by: Alexis Ballier <aballier@gentoo.org>
>     Tested-by: Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
> ---

I assume this version fixes the lifetime issues I've pointed out. I
also assume the data flow issues got solved. With that, it would look
good to me, I guess. If nobody else has comments it could be applied.

Btw. I noticed that this apparently never sets chroma_location?
Jorge Ramirez-Ortiz Sept. 19, 2017, 7:48 p.m.
On 09/19/2017 12:35 PM, wm4 wrote:
> On Mon, 11 Sep 2017 16:26:33 +0200
> Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> wrote:
>
>>      This patchset enhances Alexis Ballier's original patch and validates
>>      it using Qualcomm's Venus hardware (driver recently landed upstream
>>      [1]).
>>
>>      This has been tested on Qualcomm's DragonBoard 410c and 820c
>>      Configure/make scripts have been validated on Ubuntu 10.04 and
>>      16.04.
>>
>>      Tested decoders:
>>             - h264
>>             - h263
>>             - mpeg4
>>             - vp8
>>             - vp9
>>             - hevc
>>
>>      Tested encoders:
>>             - h264
>>             - h263
>>             - mpeg4
>>
>>      Tested transcoding (concurrent encoding/decoding)
>>
>>      Some of the changes introduced:
>>          - v4l2: code cleanup and abstractions added
>>          - v4l2: follow the new encode/decode api.
>>          - v4l2: fix display size for NV12 output pool.
>>          - v4l2: handle EOS.
>>          - v4l2: vp8 and mpeg4 decoding and encoding.
>>          - v4l2: hevc and vp9 support.
>>          - v4l2: generate EOF on dequeue errors.
>>          - v4l2: h264_mp4toannexb filtering.
>>          - v4l2: fixed make install and fate issues.
>>          - v4l2: codecs enabled/disabled depending on pixfmt defined
>>          - v4l2: pass timebase/framerate to the context
>>          - v4l2: runtime decoder reconfiguration.
>>          - v4l2: add more frame information
>>          - v4l2: free hardware resources on last reference being released
>>          - v4l2: encoding: disable b-frames for upstreaming (patch required)
>>
>>      [1] https://lwn.net/Articles/697956/
>>
>>      Reviewed-by: Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
>>      Reviewed-by: Alexis Ballier <aballier@gentoo.org>
>>      Tested-by: Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
>> ---
> I assume this version fixes the lifetime issues I've pointed out.

yes, the buffer issues  are resolved and the user can now close the 
encoder/decoder without losing the buffer references.

> I
> also assume the data flow issues got solved.

data flow?

> With that, it would look
> good to me, I guess. If nobody else has comments it could be applied.

please let me post v13 - today/tomorrow-  which cleans the code a bit more 
making it easier to understand and maintain (maybe it will trigger more questions?)

> Btw. I noticed that this apparently never sets chroma_location?

I'll look into that for v13 as well.

> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
wm4 Sept. 19, 2017, 7:54 p.m.
On Tue, 19 Sep 2017 12:48:06 -0700
Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> wrote:

> > I
> > also assume the data flow issues got solved.  
> 
> data flow?

Wasn't there some confusion about how send/receive works, and how to
connect it to how v4l2 data flow works?

(Also could we replace all instances of v4l2 with v4l? The original v4l
is dead AFAIK, and the 2 is redundant and confusing.)
Jorge Ramirez-Ortiz Sept. 19, 2017, 8:05 p.m.
On 09/19/2017 12:54 PM, wm4 wrote:
> On Tue, 19 Sep 2017 12:48:06 -0700
> Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> wrote:
>
>>> I
>>> also assume the data flow issues got solved.
>> data flow?
> Wasn't there some confusion about how send/receive works, and how to
> connect it to how v4l2 data flow works?

ah yes, you are right. yes that was fixed as well (removing the timeouts when 
waiting for buffers).

>
> (Also could we replace all instances of v4l2 with v4l? The original v4l
> is dead AFAIK, and the 2 is redundant and confusing.)

do you mind if we keep the v4l2 (after all the API is called that way); just 
that v4l doesn't mean much anymore and it might create confusion to v4l2 developers
also notice that the kernel interface file is called videodev2.h.
Jorge Ramirez-Ortiz Sept. 21, 2017, 2:01 a.m.
On 09/19/2017 12:35 PM, wm4 wrote:
> On Mon, 11 Sep 2017 16:26:33 +0200
> Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> wrote:
>
>>      This patchset enhances Alexis Ballier's original patch and validates
>>      it using Qualcomm's Venus hardware (driver recently landed upstream
>>      [1]).
>>
>>      This has been tested on Qualcomm's DragonBoard 410c and 820c
>>      Configure/make scripts have been validated on Ubuntu 10.04 and
>>      16.04.
>>
>>      Tested decoders:
>>             - h264
>>             - h263
>>             - mpeg4
>>             - vp8
>>             - vp9
>>             - hevc
>>
>>      Tested encoders:
>>             - h264
>>             - h263
>>             - mpeg4
>>
>>      Tested transcoding (concurrent encoding/decoding)
>>
>>      Some of the changes introduced:
>>          - v4l2: code cleanup and abstractions added
>>          - v4l2: follow the new encode/decode api.
>>          - v4l2: fix display size for NV12 output pool.
>>          - v4l2: handle EOS.
>>          - v4l2: vp8 and mpeg4 decoding and encoding.
>>          - v4l2: hevc and vp9 support.
>>          - v4l2: generate EOF on dequeue errors.
>>          - v4l2: h264_mp4toannexb filtering.
>>          - v4l2: fixed make install and fate issues.
>>          - v4l2: codecs enabled/disabled depending on pixfmt defined
>>          - v4l2: pass timebase/framerate to the context
>>          - v4l2: runtime decoder reconfiguration.
>>          - v4l2: add more frame information
>>          - v4l2: free hardware resources on last reference being released
>>          - v4l2: encoding: disable b-frames for upstreaming (patch required)
>>
>>      [1] https://lwn.net/Articles/697956/
>>
>>      Reviewed-by: Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
>>      Reviewed-by: Alexis Ballier <aballier@gentoo.org>
>>      Tested-by: Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
>> ---
> I assume this version fixes the lifetime issues I've pointed out. I
> also assume the data flow issues got solved. With that, it would look
> good to me, I guess. If nobody else has comments it could be applied.
>
> Btw. I noticed that this apparently never sets chroma_location?

I didnt find anything in v4l2 to retrieve the chroma_location from the kernel 
driver (the API doesnt handle this information).
does ffmpeg need this field and if so, can it be retrieved from somewhere else 
(bitstream perhaps)?

just posted v13. I think the overall quality and feature set should be 
acceptable to be merged upstream (but of course, looking forward for comments if 
not and will continue to be as responsive as possible)



> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
wm4 Sept. 21, 2017, 3:31 a.m.
On Wed, 20 Sep 2017 19:01:52 -0700
Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> wrote:

> > Btw. I noticed that this apparently never sets chroma_location?  
> 
> I didnt find anything in v4l2 to retrieve the chroma_location from the kernel 
> driver (the API doesnt handle this information).
> does ffmpeg need this field and if so, can it be retrieved from somewhere else 
> (bitstream perhaps)?

Yes, chroma location matters. Some users notice if the location is
incorrect. It can be retrieved from the bitstream, but that would
require you to parse it. Which probably would require additional code.
(You can't rely on the pre-filled parameters by libavformat, because an
API user doesn't have to use libavformat.)

I suggest you make the kernel devs add this parameter. There might be
more such missing parameters, I noticed this one only by chance.
Jorge Ramirez-Ortiz Sept. 21, 2017, 5:04 a.m.
On 09/20/2017 08:31 PM, wm4 wrote:
> On Wed, 20 Sep 2017 19:01:52 -0700
> Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> wrote:
>
>>> Btw. I noticed that this apparently never sets chroma_location?
>> I didnt find anything in v4l2 to retrieve the chroma_location from the kernel
>> driver (the API doesnt handle this information).
>> does ffmpeg need this field and if so, can it be retrieved from somewhere else
>> (bitstream perhaps)?
> Yes, chroma location matters. Some users notice if the location is
> incorrect. It can be retrieved from the bitstream, but that would
> require you to parse it. Which probably would require additional code.
> (You can't rely on the pre-filled parameters by libavformat, because an
> API user doesn't have to use libavformat.)

ok.

>
> I suggest you make the kernel devs add this parameter. There might be
> more such missing parameters, I noticed this one only by chance.

I see. I'll find out what is the process to modify the API and why the current 
drivers don't use it.
Notice that -even if the API change is accepted in the coming months - all the 
drivers currently available in the field wont be using it in the near future 
though (they will be returning a default, null I guess).

I just dont have any control on the drivers or the API itself: do you think this 
will be blocking the upstream process?

> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel

Patch hide | download patch | download mbox

diff --git a/Changelog b/Changelog
index ca0758a..03c242b 100644
--- a/Changelog
+++ b/Changelog
@@ -47,6 +47,7 @@  version <next>:
 - SUP/PGS subtitle muxer
 - convolve video filter
 - VP9 tile threading support
+- V4L2 mem2mem HW assisted codecs
 
 version 3.3:
 - CrystalHD decoder moved to new decode API
diff --git a/configure b/configure
index 4dd11ef..74a396c 100755
--- a/configure
+++ b/configure
@@ -185,6 +185,7 @@  Individual component options:
   --enable-filter=NAME     enable filter NAME
   --disable-filter=NAME    disable filter NAME
   --disable-filters        disable all filters
+  --disable-v4l2_m2m       disable V4L2 mem2mem code [autodetect]
 
 External library support:
 
@@ -1624,6 +1625,7 @@  HWACCEL_AUTODETECT_LIBRARY_LIST="
     vda
     vdpau
     videotoolbox
+    v4l2_m2m
     xvmc
 "
 
@@ -2751,6 +2753,7 @@  omx_rpi_select="omx"
 qsvdec_select="qsv"
 qsvenc_select="qsv"
 vaapi_encode_deps="vaapi"
+v4l2_m2m_deps_any="linux_videodev2_h"
 
 hwupload_cuda_filter_deps="cuda"
 scale_npp_filter_deps="cuda libnpp"
@@ -2760,6 +2763,8 @@  nvenc_deps="cuda"
 nvenc_deps_any="dlopen LoadLibrary"
 nvenc_encoder_deps="nvenc"
 
+h263_v4l2m2m_decoder_deps="v4l2_m2m h263_v4l2_m2m"
+h263_v4l2m2m_encoder_deps="v4l2_m2m h263_v4l2_m2m"
 h264_crystalhd_decoder_select="crystalhd h264_mp4toannexb_bsf h264_parser"
 h264_cuvid_decoder_deps="cuda cuvid"
 h264_cuvid_decoder_select="h264_mp4toannexb_bsf"
@@ -2778,6 +2783,8 @@  h264_vda_decoder_deps="vda"
 h264_vda_decoder_select="h264_decoder"
 h264_vdpau_decoder_deps="vdpau"
 h264_vdpau_decoder_select="h264_decoder"
+h264_v4l2m2m_decoder_deps="v4l2_m2m h264_v4l2_m2m"
+h264_v4l2m2m_encoder_deps="v4l2_m2m h264_v4l2_m2m"
 hevc_cuvid_decoder_deps="cuda cuvid"
 hevc_cuvid_decoder_select="hevc_mp4toannexb_bsf"
 hevc_mediacodec_decoder_deps="mediacodec"
@@ -2789,12 +2796,15 @@  hevc_qsv_encoder_deps="libmfx"
 hevc_qsv_encoder_select="hevcparse qsvenc"
 hevc_vaapi_encoder_deps="VAEncPictureParameterBufferHEVC"
 hevc_vaapi_encoder_select="vaapi_encode golomb"
+hevc_v4l2m2m_decoder_deps="v4l2_m2m hevc_v4l2_m2m"
+hevc_v4l2m2m_encoder_deps="v4l2_m2m hevc_v4l2_m2m"
 mjpeg_cuvid_decoder_deps="cuda cuvid"
 mjpeg_vaapi_encoder_deps="VAEncPictureParameterBufferJPEG"
 mjpeg_vaapi_encoder_select="vaapi_encode jpegtables"
 mpeg1_cuvid_decoder_deps="cuda cuvid"
 mpeg1_vdpau_decoder_deps="vdpau"
 mpeg1_vdpau_decoder_select="mpeg1video_decoder"
+mpeg1_v4l2m2m_decoder_deps="v4l2_m2m mpeg1_v4l2_m2m"
 mpeg2_crystalhd_decoder_select="crystalhd"
 mpeg2_cuvid_decoder_deps="cuda cuvid"
 mpeg2_mmal_decoder_deps="mmal"
@@ -2805,6 +2815,7 @@  mpeg2_qsv_encoder_deps="libmfx"
 mpeg2_qsv_encoder_select="qsvenc"
 mpeg2_vaapi_encoder_deps="VAEncPictureParameterBufferMPEG2"
 mpeg2_vaapi_encoder_select="vaapi_encode"
+mpeg2_v4l2m2m_decoder_deps="v4l2_m2m mpeg2_v4l2_m2m"
 mpeg4_crystalhd_decoder_select="crystalhd"
 mpeg4_cuvid_decoder_deps="cuda cuvid"
 mpeg4_mediacodec_decoder_deps="mediacodec"
@@ -2812,6 +2823,8 @@  mpeg4_mmal_decoder_deps="mmal"
 mpeg4_omx_encoder_deps="omx"
 mpeg4_vdpau_decoder_deps="vdpau"
 mpeg4_vdpau_decoder_select="mpeg4_decoder"
+mpeg4_v4l2m2m_decoder_deps="v4l2_m2m mpeg4_v4l2_m2m"
+mpeg4_v4l2m2m_encoder_deps="v4l2_m2m mpeg4_v4l2_m2m"
 mpeg_vdpau_decoder_deps="vdpau"
 mpeg_vdpau_decoder_select="mpeg2video_decoder"
 msmpeg4_crystalhd_decoder_select="crystalhd"
@@ -2822,16 +2835,20 @@  vc1_cuvid_decoder_deps="cuda cuvid"
 vc1_mmal_decoder_deps="mmal"
 vc1_vdpau_decoder_deps="vdpau"
 vc1_vdpau_decoder_select="vc1_decoder"
+vc1_v4l2m2m_decoder_deps="v4l2_m2m vc1_v4l2_m2m"
 vp8_cuvid_decoder_deps="cuda cuvid"
 vp8_mediacodec_decoder_deps="mediacodec"
 vp8_qsv_decoder_deps="libmfx"
 vp8_qsv_decoder_select="qsvdec vp8_qsv_hwaccel vp8_parser"
 vp8_vaapi_encoder_deps="VAEncPictureParameterBufferVP8"
 vp8_vaapi_encoder_select="vaapi_encode"
+vp8_v4l2m2m_decoder_deps="v4l2_m2m vp8_v4l2_m2m"
+vp8_v4l2m2m_encoder_deps="v4l2_m2m vp8_v4l2_m2m"
 vp9_cuvid_decoder_deps="cuda cuvid"
 vp9_mediacodec_decoder_deps="mediacodec"
 vp9_vaapi_encoder_deps="VAEncPictureParameterBufferVP9"
 vp9_vaapi_encoder_select="vaapi_encode"
+vp9_v4l2m2m_decoder_deps="v4l2_m2m vp9_v4l2_m2m"
 wmv3_crystalhd_decoder_select="crystalhd"
 wmv3_vdpau_decoder_select="vc1_vdpau_decoder"
 
@@ -6095,9 +6112,20 @@  perl -v            > /dev/null 2>&1 && enable perl      || disable perl
 pod2man --help     > /dev/null 2>&1 && enable pod2man   || disable pod2man
 rsync --help 2> /dev/null | grep -q 'contimeout' && enable rsync_contimeout || disable rsync_contimeout
 
+# check V4L2 codecs available in the API
 check_header linux/fb.h
 check_header linux/videodev2.h
 check_code cc linux/videodev2.h "struct v4l2_frmsizeenum vfse; vfse.discrete.width = 0;" && enable_safe struct_v4l2_frmivalenum_discrete
+check_code cc linux/videodev2.h "int i = V4L2_CAP_VIDEO_M2M_MPLANE | V4L2_CAP_VIDEO_M2M | V4L2_BUF_FLAG_LAST;" || disable v4l2_m2m
+check_code cc linux/videodev2.h "int i = V4L2_PIX_FMT_VC1_ANNEX_G;" && enable vc1_v4l2_m2m
+check_code cc linux/videodev2.h "int i = V4L2_PIX_FMT_MPEG1;" && enable mpeg1_v4l2_m2m
+check_code cc linux/videodev2.h "int i = V4L2_PIX_FMT_MPEG2;" && enable mpeg2_v4l2_m2m
+check_code cc linux/videodev2.h "int i = V4L2_PIX_FMT_MPEG4;" && enable mpeg4_v4l2_m2m
+check_code cc linux/videodev2.h "int i = V4L2_PIX_FMT_HEVC;" && enable hevc_v4l2_m2m
+check_code cc linux/videodev2.h "int i = V4L2_PIX_FMT_H263;" && enable h263_v4l2_m2m
+check_code cc linux/videodev2.h "int i = V4L2_PIX_FMT_H264;" && enable h264_v4l2_m2m
+check_code cc linux/videodev2.h "int i = V4L2_PIX_FMT_VP8;" && enable vp8_v4l2_m2m
+check_code cc linux/videodev2.h "int i = V4L2_PIX_FMT_VP9;" && enable vp9_v4l2_m2m
 
 check_header sys/videoio.h
 check_code cc sys/videoio.h "struct v4l2_frmsizeenum vfse; vfse.discrete.width = 0;" && enable_safe struct_v4l2_frmivalenum_discrete
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 999632c..68193ec 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -137,6 +137,7 @@  OBJS-$(CONFIG_VIDEODSP)                += videodsp.o
 OBJS-$(CONFIG_VP3DSP)                  += vp3dsp.o
 OBJS-$(CONFIG_VP56DSP)                 += vp56dsp.o
 OBJS-$(CONFIG_VP8DSP)                  += vp8dsp.o
+OBJS-$(CONFIG_V4L2_M2M)                += v4l2_m2m.o v4l2_context.o v4l2_buffers.o v4l2_fmt.o
 OBJS-$(CONFIG_WMA_FREQS)               += wma_freqs.o
 OBJS-$(CONFIG_WMV2DSP)                 += wmv2dsp.o
 
@@ -323,6 +324,8 @@  OBJS-$(CONFIG_H263_DECODER)            += h263dec.o h263.o ituh263dec.o        \
                                           intelh263dec.o h263data.o
 OBJS-$(CONFIG_H263_ENCODER)            += mpeg4videoenc.o mpeg4video.o  \
                                           h263.o ituh263enc.o flvenc.o h263data.o
+OBJS-$(CONFIG_H263_V4L2M2M_DECODER)    += v4l2_m2m_dec.o
+OBJS-$(CONFIG_H263_V4L2M2M_ENCODER)    += v4l2_m2m_enc.o
 OBJS-$(CONFIG_H264_DECODER)            += h264dec.o h264_cabac.o h264_cavlc.o \
                                           h264_direct.o h264_loopfilter.o  \
                                           h264_mb.o h264_picture.o \
@@ -340,6 +343,8 @@  OBJS-$(CONFIG_H264_QSV_DECODER)        += qsvdec_h2645.o
 OBJS-$(CONFIG_H264_QSV_ENCODER)        += qsvenc_h264.o
 OBJS-$(CONFIG_H264_VAAPI_ENCODER)      += vaapi_encode_h264.o vaapi_encode_h26x.o
 OBJS-$(CONFIG_H264_VIDEOTOOLBOX_ENCODER) += videotoolboxenc.o
+OBJS-$(CONFIG_H264_V4L2M2M_DECODER)    += v4l2_m2m_dec.o
+OBJS-$(CONFIG_H264_V4L2M2M_ENCODER)    += v4l2_m2m_enc.o
 OBJS-$(CONFIG_HAP_DECODER)             += hapdec.o hap.o
 OBJS-$(CONFIG_HAP_ENCODER)             += hapenc.o hap.o
 OBJS-$(CONFIG_HEVC_DECODER)            += hevcdec.o hevc_mvs.o \
@@ -353,6 +358,8 @@  OBJS-$(CONFIG_HEVC_QSV_DECODER)        += qsvdec_h2645.o
 OBJS-$(CONFIG_HEVC_QSV_ENCODER)        += qsvenc_hevc.o hevc_ps_enc.o       \
                                           hevc_data.o
 OBJS-$(CONFIG_HEVC_VAAPI_ENCODER)      += vaapi_encode_h265.o vaapi_encode_h26x.o
+OBJS-$(CONFIG_HEVC_V4L2M2M_DECODER)    += v4l2_m2m_dec.o
+OBJS-$(CONFIG_HEVC_V4L2M2M_ENCODER)    += v4l2_m2m_enc.o
 OBJS-$(CONFIG_HNM4_VIDEO_DECODER)      += hnm4video.o
 OBJS-$(CONFIG_HQ_HQA_DECODER)          += hq_hqa.o hq_hqadata.o hq_hqadsp.o \
                                           canopus.o
@@ -422,6 +429,7 @@  OBJS-$(CONFIG_MPC8_DECODER)            += mpc8.o mpc.o
 OBJS-$(CONFIG_MPEGVIDEO_DECODER)       += mpeg12dec.o mpeg12.o mpeg12data.o
 OBJS-$(CONFIG_MPEG1VIDEO_DECODER)      += mpeg12dec.o mpeg12.o mpeg12data.o
 OBJS-$(CONFIG_MPEG1VIDEO_ENCODER)      += mpeg12enc.o mpeg12.o
+OBJS-$(CONFIG_MPEG1_V4L2M2M_DECODER)   += v4l2_m2m_dec.o
 OBJS-$(CONFIG_MPEG2_MMAL_DECODER)      += mmaldec.o
 OBJS-$(CONFIG_MPEG2_QSV_DECODER)       += qsvdec_other.o
 OBJS-$(CONFIG_MPEG2_QSV_ENCODER)       += qsvenc_mpeg2.o
@@ -429,9 +437,12 @@  OBJS-$(CONFIG_MPEG2VIDEO_DECODER)      += mpeg12dec.o mpeg12.o mpeg12data.o
 OBJS-$(CONFIG_MPEG2VIDEO_ENCODER)      += mpeg12enc.o mpeg12.o
 OBJS-$(CONFIG_MPEG2_MEDIACODEC_DECODER) += mediacodecdec.o
 OBJS-$(CONFIG_MPEG2_VAAPI_ENCODER)     += vaapi_encode_mpeg2.o
+OBJS-$(CONFIG_MPEG2_V4L2M2M_DECODER)   += v4l2_m2m_dec.o
 OBJS-$(CONFIG_MPEG4_DECODER)           += xvididct.o
 OBJS-$(CONFIG_MPEG4_MEDIACODEC_DECODER) += mediacodecdec.o
 OBJS-$(CONFIG_MPEG4_OMX_ENCODER)       += omx.o
+OBJS-$(CONFIG_MPEG4_V4L2M2M_DECODER)   += v4l2_m2m_dec.o
+OBJS-$(CONFIG_MPEG4_V4L2M2M_ENCODER)   += v4l2_m2m_enc.o
 OBJS-$(CONFIG_MPL2_DECODER)            += mpl2dec.o ass.o
 OBJS-$(CONFIG_MSA1_DECODER)            += mss3.o
 OBJS-$(CONFIG_MSCC_DECODER)            += mscc.o
@@ -605,6 +616,7 @@  OBJS-$(CONFIG_VC1_DECODER)             += vc1dec.o vc1_block.o vc1_loopfilter.o
 OBJS-$(CONFIG_VC1_CUVID_DECODER)       += cuvid.o
 OBJS-$(CONFIG_VC1_MMAL_DECODER)        += mmaldec.o
 OBJS-$(CONFIG_VC1_QSV_DECODER)         += qsvdec_other.o
+OBJS-$(CONFIG_VC1_V4L2M2M_DECODER)     += v4l2_m2m_dec.o
 OBJS-$(CONFIG_VC2_ENCODER)             += vc2enc.o vc2enc_dwt.o diractab.o
 OBJS-$(CONFIG_VCR1_DECODER)            += vcr1.o
 OBJS-$(CONFIG_VMDAUDIO_DECODER)        += vmdaudio.o
@@ -624,6 +636,8 @@  OBJS-$(CONFIG_VP8_CUVID_DECODER)       += cuvid.o
 OBJS-$(CONFIG_VP8_MEDIACODEC_DECODER)  += mediacodecdec.o
 OBJS-$(CONFIG_VP8_QSV_DECODER)         += qsvdec_other.o
 OBJS-$(CONFIG_VP8_VAAPI_ENCODER)       += vaapi_encode_vp8.o
+OBJS-$(CONFIG_VP8_V4L2M2M_DECODER)     += v4l2_m2m_dec.o
+OBJS-$(CONFIG_VP8_V4L2M2M_ENCODER)     += v4l2_m2m_enc.o
 OBJS-$(CONFIG_VP9_DECODER)             += vp9.o vp9data.o vp9dsp.o vp9lpf.o vp9recon.o \
                                           vp9block.o vp9prob.o vp9mvs.o vp56rac.o \
                                           vp9dsp_8bpp.o vp9dsp_10bpp.o vp9dsp_12bpp.o
@@ -631,6 +645,7 @@  OBJS-$(CONFIG_VP9_CUVID_DECODER)       += cuvid.o
 OBJS-$(CONFIG_VP9_MEDIACODEC_DECODER)  += mediacodecdec.o
 OBJS-$(CONFIG_VP9_VAAPI_ENCODER)       += vaapi_encode_vp9.o
 OBJS-$(CONFIG_VPLAYER_DECODER)         += textdec.o ass.o
+OBJS-$(CONFIG_VP9_V4L2M2M_DECODER)     += v4l2_m2m_dec.o
 OBJS-$(CONFIG_VQA_DECODER)             += vqavideo.o
 OBJS-$(CONFIG_WAVPACK_DECODER)         += wavpack.o
 OBJS-$(CONFIG_WAVPACK_ENCODER)         += wavpackenc.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index ce0bc7e..756ce56 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -208,8 +208,10 @@  static void register_all(void)
     REGISTER_ENCDEC (H263,              h263);
     REGISTER_DECODER(H263I,             h263i);
     REGISTER_ENCDEC (H263P,             h263p);
+    REGISTER_ENCDEC (H263_V4L2M2M,      h263_v4l2m2m);
     REGISTER_DECODER(H264,              h264);
     REGISTER_DECODER(H264_CRYSTALHD,    h264_crystalhd);
+    REGISTER_ENCDEC (H264_V4L2M2M,      h264_v4l2m2m);
     REGISTER_DECODER(H264_MEDIACODEC,   h264_mediacodec);
     REGISTER_DECODER(H264_MMAL,         h264_mmal);
     REGISTER_DECODER(H264_QSV,          h264_qsv);
@@ -220,6 +222,7 @@  static void register_all(void)
     REGISTER_ENCDEC (HAP,               hap);
     REGISTER_DECODER(HEVC,              hevc);
     REGISTER_DECODER(HEVC_QSV,          hevc_qsv);
+    REGISTER_ENCDEC (HEVC_V4L2M2M,      hevc_v4l2m2m);
     REGISTER_DECODER(HNM4_VIDEO,        hnm4_video);
     REGISTER_DECODER(HQ_HQA,            hq_hqa);
     REGISTER_DECODER(HQX,               hqx);
@@ -254,6 +257,7 @@  static void register_all(void)
     REGISTER_ENCDEC (MPEG2VIDEO,        mpeg2video);
     REGISTER_ENCDEC (MPEG4,             mpeg4);
     REGISTER_DECODER(MPEG4_CRYSTALHD,   mpeg4_crystalhd);
+    REGISTER_ENCDEC (MPEG4_V4L2M2M,     mpeg4_v4l2m2m);
     REGISTER_DECODER(MPEG4_MMAL,        mpeg4_mmal);
 #if FF_API_VDPAU
     REGISTER_DECODER(MPEG4_VDPAU,       mpeg4_vdpau);
@@ -263,8 +267,10 @@  static void register_all(void)
     REGISTER_DECODER(MPEG_VDPAU,        mpeg_vdpau);
     REGISTER_DECODER(MPEG1_VDPAU,       mpeg1_vdpau);
 #endif
+    REGISTER_DECODER(MPEG1_V4L2M2M,     mpeg1_v4l2m2m);
     REGISTER_DECODER(MPEG2_MMAL,        mpeg2_mmal);
     REGISTER_DECODER(MPEG2_CRYSTALHD,   mpeg2_crystalhd);
+    REGISTER_DECODER(MPEG2_V4L2M2M,     mpeg2_v4l2m2m);
     REGISTER_DECODER(MPEG2_QSV,         mpeg2_qsv);
     REGISTER_DECODER(MPEG2_MEDIACODEC,  mpeg2_mediacodec);
     REGISTER_DECODER(MSA1,              msa1);
@@ -362,6 +368,7 @@  static void register_all(void)
     REGISTER_DECODER(VC1IMAGE,          vc1image);
     REGISTER_DECODER(VC1_MMAL,          vc1_mmal);
     REGISTER_DECODER(VC1_QSV,           vc1_qsv);
+    REGISTER_DECODER(VC1_V4L2M2M,       vc1_v4l2m2m);
     REGISTER_ENCODER(VC2,               vc2);
     REGISTER_DECODER(VCR1,              vcr1);
     REGISTER_DECODER(VMDVIDEO,          vmdvideo);
@@ -373,7 +380,9 @@  static void register_all(void)
     REGISTER_DECODER(VP6F,              vp6f);
     REGISTER_DECODER(VP7,               vp7);
     REGISTER_DECODER(VP8,               vp8);
+    REGISTER_ENCDEC (VP8_V4L2M2M,       vp8_v4l2m2m);
     REGISTER_DECODER(VP9,               vp9);
+    REGISTER_DECODER(VP9_V4L2M2M,       vp9_v4l2m2m);
     REGISTER_DECODER(VQA,               vqa);
     REGISTER_DECODER(BITPACKED,         bitpacked);
     REGISTER_DECODER(WEBP,              webp);
diff --git a/libavcodec/v4l2_buffers.c b/libavcodec/v4l2_buffers.c
new file mode 100644
index 0000000..939bbd4
--- /dev/null
+++ b/libavcodec/v4l2_buffers.c
@@ -0,0 +1,448 @@ 
+/*
+ * V4L2 buffer helper functions.
+ *
+ * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
+ * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/videodev2.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <poll.h>
+#include "libavcodec/avcodec.h"
+#include "libavcodec/internal.h"
+#include "v4l2_context.h"
+#include "v4l2_buffers.h"
+#include "v4l2_m2m.h"
+
+#define USEC_PER_SEC 1000000
+
+static inline V4L2m2mContext *buf_to_m2mctx(V4L2Buffer *buf)
+{
+    return V4L2_TYPE_IS_OUTPUT(buf->context->type) ?
+        container_of(buf->context, V4L2m2mContext, output) :
+        container_of(buf->context, V4L2m2mContext, capture);
+}
+
+static inline void v4l2_set_pts(V4L2Buffer *out, int64_t pts)
+{
+    V4L2m2mContext *s = buf_to_m2mctx(out);
+    AVRational v4l2_timebase = { 1, USEC_PER_SEC };
+    int64_t v4l2_pts;
+
+    if (pts == AV_NOPTS_VALUE)
+        pts = 0;
+
+    /* convert pts to v4l2 timebase */
+    v4l2_pts = av_rescale_q(pts, s->avctx->time_base, v4l2_timebase);
+    out->buf.timestamp.tv_usec = v4l2_pts % USEC_PER_SEC;
+    out->buf.timestamp.tv_sec = v4l2_pts / USEC_PER_SEC;
+}
+
+static inline uint64_t v4l2_get_pts(V4L2Buffer *avbuf)
+{
+    V4L2m2mContext *s = buf_to_m2mctx(avbuf);
+    AVRational v4l2_timebase = { 1, USEC_PER_SEC };
+    int64_t v4l2_pts;
+
+    /* convert pts back to encoder timebase */
+    v4l2_pts = avbuf->buf.timestamp.tv_sec * USEC_PER_SEC + avbuf->buf.timestamp.tv_usec;
+
+    return av_rescale_q(v4l2_pts, v4l2_timebase, s->avctx->time_base);
+}
+
+static enum AVColorPrimaries v4l2_get_color_primaries(V4L2Buffer *buf)
+{
+    enum v4l2_ycbcr_encoding ycbcr;
+    enum v4l2_colorspace cs;
+
+    cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
+        buf->context->format.fmt.pix_mp.colorspace :
+        buf->context->format.fmt.pix.colorspace;
+
+    ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
+        buf->context->format.fmt.pix_mp.ycbcr_enc:
+        buf->context->format.fmt.pix.ycbcr_enc;
+
+    switch(ycbcr) {
+    case V4L2_YCBCR_ENC_XV709:
+    case V4L2_YCBCR_ENC_709: return AVCOL_PRI_BT709;
+    case V4L2_YCBCR_ENC_XV601:
+    case V4L2_YCBCR_ENC_601:return AVCOL_PRI_BT470M;
+    default:
+        break;
+    }
+
+    switch(cs) {
+    case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_PRI_BT470BG;
+    case V4L2_COLORSPACE_SMPTE170M: return AVCOL_PRI_SMPTE170M;
+    case V4L2_COLORSPACE_SMPTE240M: return AVCOL_PRI_SMPTE240M;
+    case V4L2_COLORSPACE_BT2020: return AVCOL_PRI_BT2020;
+    default:
+        break;
+    }
+
+    return AVCOL_PRI_UNSPECIFIED;
+}
+
+static enum AVColorRange v4l2_get_color_range(V4L2Buffer *buf)
+{
+    enum v4l2_quantization qt;
+
+    qt = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
+        buf->context->format.fmt.pix_mp.quantization :
+        buf->context->format.fmt.pix.quantization;
+
+    switch (qt) {
+    case V4L2_QUANTIZATION_LIM_RANGE: return AVCOL_RANGE_MPEG;
+    case V4L2_QUANTIZATION_FULL_RANGE: return AVCOL_RANGE_JPEG;
+    default:
+        break;
+    }
+
+     return AVCOL_RANGE_UNSPECIFIED;
+}
+
+static enum AVColorSpace v4l2_get_color_space(V4L2Buffer *buf)
+{
+    enum v4l2_ycbcr_encoding ycbcr;
+    enum v4l2_colorspace cs;
+
+    cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
+        buf->context->format.fmt.pix_mp.colorspace :
+        buf->context->format.fmt.pix.colorspace;
+
+    ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
+        buf->context->format.fmt.pix_mp.ycbcr_enc:
+        buf->context->format.fmt.pix.ycbcr_enc;
+
+    switch(cs) {
+    case V4L2_COLORSPACE_SRGB: return AVCOL_SPC_RGB;
+    case V4L2_COLORSPACE_REC709: return AVCOL_SPC_BT709;
+    case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_SPC_FCC;
+    case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_SPC_BT470BG;
+    case V4L2_COLORSPACE_SMPTE170M: return AVCOL_SPC_SMPTE170M;
+    case V4L2_COLORSPACE_SMPTE240M: return AVCOL_SPC_SMPTE240M;
+    case V4L2_COLORSPACE_BT2020:
+        if (ycbcr == V4L2_YCBCR_ENC_BT2020_CONST_LUM)
+            return AVCOL_SPC_BT2020_CL;
+        else
+             return AVCOL_SPC_BT2020_NCL;
+    default:
+        break;
+    }
+
+    return AVCOL_SPC_UNSPECIFIED;
+}
+
+static enum AVColorTransferCharacteristic v4l2_get_color_trc(V4L2Buffer *buf)
+{
+    enum v4l2_ycbcr_encoding ycbcr;
+    enum v4l2_xfer_func xfer;
+    enum v4l2_colorspace cs;
+
+    cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
+        buf->context->format.fmt.pix_mp.colorspace :
+        buf->context->format.fmt.pix.colorspace;
+
+    ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
+        buf->context->format.fmt.pix_mp.ycbcr_enc:
+        buf->context->format.fmt.pix.ycbcr_enc;
+
+    xfer = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
+        buf->context->format.fmt.pix_mp.xfer_func:
+        buf->context->format.fmt.pix.xfer_func;
+
+    switch (xfer) {
+    case V4L2_XFER_FUNC_709: return AVCOL_TRC_BT709;
+    case V4L2_XFER_FUNC_SRGB: return AVCOL_TRC_IEC61966_2_1;
+    default:
+        break;
+    }
+
+    switch (cs) {
+    case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_TRC_GAMMA22;
+    case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_TRC_GAMMA28;
+    case V4L2_COLORSPACE_SMPTE170M: return AVCOL_TRC_SMPTE170M;
+    case V4L2_COLORSPACE_SMPTE240M: return AVCOL_TRC_SMPTE240M;
+    default:
+        break;
+    }
+
+    switch (ycbcr) {
+    case V4L2_YCBCR_ENC_XV709:
+    case V4L2_YCBCR_ENC_XV601: return AVCOL_TRC_BT1361_ECG;
+    default:
+        break;
+    }
+
+    return AVCOL_TRC_UNSPECIFIED;
+}
+
+static void v4l2_free_buffer(void *opaque, uint8_t *unused)
+{
+    V4L2Buffer* avbuf = opaque;
+    V4L2m2mContext *s = buf_to_m2mctx(avbuf);
+
+    atomic_fetch_sub_explicit(&s->refcount, 1, memory_order_acq_rel);
+    if (s->reinit) {
+        if (!atomic_load(&s->refcount))
+            sem_post(&s->refsync);
+        return;
+    }
+
+    if (avbuf->context->streamon) {
+        ff_v4l2_buffer_enqueue(avbuf);
+        return;
+    }
+
+    if (!atomic_load(&s->refcount))
+        ff_v4l2_m2m_codec_end(s->avctx);
+}
+
+static int v4l2_buf_to_bufref(V4L2Buffer *in, int plane, AVBufferRef **buf)
+{
+    V4L2m2mContext *s = buf_to_m2mctx(in);
+
+    if (plane >= in->num_planes)
+        return AVERROR(EINVAL);
+
+    /* even though most encoders return 0 in data_offset encoding vp8 does require this value */
+    *buf = av_buffer_create((char *)in->plane_info[plane].mm_addr + in->planes[plane].data_offset,
+                            in->plane_info[plane].length, v4l2_free_buffer, in, 0);
+    if (!*buf)
+        return AVERROR(ENOMEM);
+
+    in->status = V4L2BUF_RET_USER;
+    atomic_fetch_add_explicit(&s->refcount, 1, memory_order_relaxed);
+
+    return 0;
+}
+
+static int v4l2_bufref_to_buf(V4L2Buffer *out, int plane, const uint8_t* data, int size, AVBufferRef* bref)
+{
+    if (plane >= out->num_planes)
+        return AVERROR(EINVAL);
+
+    memcpy(out->plane_info[plane].mm_addr, data, FFMIN(size, out->plane_info[plane].length));
+
+    out->planes[plane].bytesused = FFMIN(size, out->plane_info[plane].length);
+    out->planes[plane].length = out->plane_info[plane].length;
+
+    return 0;
+}
+
+/******************************************************************************
+ *
+ *              V4L2uffer interface
+ *
+ ******************************************************************************/
+
+int ff_v4l2_buffer_avframe_to_buf(const AVFrame *frame, V4L2Buffer* out)
+{
+    int i, ret;
+
+    for(i = 0; i < out->num_planes; i++) {
+        ret = v4l2_bufref_to_buf(out, i, frame->buf[i]->data, frame->buf[i]->size, frame->buf[i]);
+        if (ret)
+            return ret;
+    }
+
+    v4l2_set_pts(out, frame->pts);
+
+    return 0;
+}
+
+int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *avbuf)
+{
+    V4L2m2mContext *s = buf_to_m2mctx(avbuf);
+    int i, ret;
+
+    av_frame_unref(frame);
+
+    /* 1. get references to the actual data */
+    for (i = 0; i < avbuf->num_planes; i++) {
+        ret = v4l2_buf_to_bufref(avbuf, i, &frame->buf[i]);
+        if (ret)
+            return ret;
+
+        frame->linesize[i] = avbuf->plane_info[i].bytesperline;
+        frame->data[i] = frame->buf[i]->data;
+    }
+
+    /* 1.1 fixup special cases */
+    switch (avbuf->context->av_pix_fmt) {
+    case AV_PIX_FMT_NV12:
+        if (avbuf->num_planes > 1)
+            break;
+        frame->linesize[1] = avbuf->plane_info[0].bytesperline;
+        frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
+        break;
+    default:
+        break;
+    }
+
+    /* 2. get frame information */
+    frame->key_frame = !!(avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME);
+    frame->format = avbuf->context->av_pix_fmt;
+    frame->color_primaries = v4l2_get_color_primaries(avbuf);
+    frame->colorspace = v4l2_get_color_space(avbuf);
+    frame->color_range = v4l2_get_color_range(avbuf);
+    frame->color_trc = v4l2_get_color_trc(avbuf);
+    frame->pts = v4l2_get_pts(avbuf);
+
+    /* these two values are updated also during re-init in v4l2_process_driver_event */
+    frame->height = s->output.height;
+    frame->width = s->output.width;
+
+    /* 3. report errors upstream */
+    if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
+        av_log(avbuf->context->log_ctx, AV_LOG_ERROR, "%s: driver decode error\n", avbuf->context->name);
+        frame->decode_error_flags |= FF_DECODE_ERROR_INVALID_BITSTREAM;
+    }
+
+    return 0;
+}
+
+int ff_v4l2_buffer_buf_to_avpkt(AVPacket *pkt, V4L2Buffer *avbuf)
+{
+    int ret;
+
+    av_packet_unref(pkt);
+    ret = v4l2_buf_to_bufref(avbuf, 0, &pkt->buf);
+    if (ret)
+        return ret;
+
+    pkt->size = V4L2_TYPE_IS_MULTIPLANAR(avbuf->buf.type) ? avbuf->buf.m.planes[0].bytesused : avbuf->buf.bytesused;
+    pkt->data = pkt->buf->data;
+
+    if (avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME)
+        pkt->flags |= AV_PKT_FLAG_KEY;
+
+    if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
+        av_log(avbuf->context->log_ctx, AV_LOG_ERROR, "%s driver encode error\n", avbuf->context->name);
+        pkt->flags |= AV_PKT_FLAG_CORRUPT;
+    }
+
+    pkt->dts = pkt->pts = v4l2_get_pts(avbuf);
+
+    return 0;
+}
+
+int ff_v4l2_buffer_avpkt_to_buf(const AVPacket *pkt, V4L2Buffer *out)
+{
+    int ret;
+
+    ret = v4l2_bufref_to_buf(out, 0, pkt->data, pkt->size, pkt->buf);
+    if (ret)
+        return ret;
+
+    v4l2_set_pts(out, pkt->pts);
+
+    if (pkt->flags & AV_PKT_FLAG_KEY)
+        out->flags = V4L2_BUF_FLAG_KEYFRAME;
+
+    return 0;
+}
+
+int ff_v4l2_buffer_initialize(V4L2Buffer* avbuf, int index)
+{
+    V4L2Context *ctx = avbuf->context;
+    int ret, i;
+
+    avbuf->buf.memory = V4L2_MEMORY_MMAP;
+    avbuf->buf.type = ctx->type;
+    avbuf->buf.index = index;
+
+    if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
+        avbuf->buf.length = VIDEO_MAX_PLANES;
+        avbuf->buf.m.planes = avbuf->planes;
+    }
+
+    ret = ioctl(ctx->fd, VIDIOC_QUERYBUF, &avbuf->buf);
+    if (ret < 0)
+        return AVERROR(errno);
+
+    if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
+        avbuf->num_planes = 0;
+        for (;;) {
+            /* in MP, the V4L2 API states that buf.length means num_planes */
+            if (avbuf->num_planes >= avbuf->buf.length)
+                break;
+            if (avbuf->buf.m.planes[avbuf->num_planes].length)
+                avbuf->num_planes++;
+        }
+    } else
+        avbuf->num_planes = 1;
+
+    for (i = 0; i < avbuf->num_planes; i++) {
+
+        avbuf->plane_info[i].bytesperline = V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ?
+            ctx->format.fmt.pix_mp.plane_fmt[i].bytesperline :
+            ctx->format.fmt.pix.bytesperline;
+
+        if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
+            avbuf->plane_info[i].length = avbuf->buf.m.planes[i].length;
+            avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.m.planes[i].length,
+                                           PROT_READ | PROT_WRITE, MAP_SHARED,
+                                           ctx->fd, avbuf->buf.m.planes[i].m.mem_offset);
+        } else {
+            avbuf->plane_info[i].length = avbuf->buf.length;
+            avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.length,
+                                          PROT_READ | PROT_WRITE, MAP_SHARED,
+                                          ctx->fd, avbuf->buf.m.offset);
+        }
+
+        if (avbuf->plane_info[i].mm_addr == MAP_FAILED)
+            return AVERROR(ENOMEM);
+    }
+
+    avbuf->status = V4L2BUF_AVAILABLE;
+
+    if (V4L2_TYPE_IS_OUTPUT(ctx->type))
+        return 0;
+
+    if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
+        avbuf->buf.m.planes = avbuf->planes;
+        avbuf->buf.length   = avbuf->num_planes;
+
+    } else {
+        avbuf->buf.bytesused = avbuf->planes[0].bytesused;
+        avbuf->buf.length    = avbuf->planes[0].length;
+    }
+
+    return ff_v4l2_buffer_enqueue(avbuf);
+}
+
+int ff_v4l2_buffer_enqueue(V4L2Buffer* avbuf)
+{
+    int ret;
+
+    avbuf->buf.flags = avbuf->flags;
+
+    ret = ioctl(avbuf->context->fd, VIDIOC_QBUF, &avbuf->buf);
+    if (ret < 0)
+        return AVERROR(errno);
+
+    avbuf->status = V4L2BUF_IN_DRIVER;
+
+    return 0;
+}
diff --git a/libavcodec/v4l2_buffers.h b/libavcodec/v4l2_buffers.h
new file mode 100644
index 0000000..8901a09
--- /dev/null
+++ b/libavcodec/v4l2_buffers.h
@@ -0,0 +1,121 @@ 
+/*
+ * V4L2 buffer helper functions.
+ *
+ * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
+ * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_V4L2_BUFFERS_H
+#define AVCODEC_V4L2_BUFFERS_H
+
+enum V4L2Buffer_status {
+    V4L2BUF_AVAILABLE,
+    V4L2BUF_IN_DRIVER,
+    V4L2BUF_RET_USER,
+};
+
+/**
+ * V4L2Buffer (wrapper for v4l2_buffer management)
+ */
+typedef struct V4L2Buffer {
+    /* each buffer needs to have a reference to its context */
+    struct V4L2Context *context;
+
+    /* keep track of the mmap address and mmap length */
+    struct V4L2Plane_info {
+        int bytesperline;
+        void * mm_addr;
+        size_t length;
+    } plane_info[VIDEO_MAX_PLANES];
+
+    int num_planes;
+
+    /* the v4l2_buffer buf.m.planes pointer uses the planes[] mem */
+    struct v4l2_buffer buf;
+    struct v4l2_plane planes[VIDEO_MAX_PLANES];
+
+    int flags;
+    enum V4L2Buffer_status status;
+
+} V4L2Buffer;
+
+/**
+ * Extracts the data from a V4L2Buffer to an AVFrame
+ *
+ * @param[in] frame The AVFRame to push the information to
+ * @param[in] buf The V4L2Buffer to get the information from
+ *
+ * @returns 0 in case of success, EINVAL if the number of planes is incorrect,
+ * ENOMEM if the AVBufferRef cant be created.
+ */
+int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *buf);
+
+/**
+ * Extracts the data from a V4L2Buffer to an AVPacket
+ *
+ * @param[in] pkt The AVPacket to push the information to
+ * @param[in] buf The V4L2Buffer to get the information from
+ *
+ * @returns 0 in case of success, EINVAL if the number of planes is incorrect,
+ * ENOMEM if the AVBufferRef cant be created.
+ *
+ */
+int ff_v4l2_buffer_buf_to_avpkt(AVPacket *pkt, V4L2Buffer *buf);
+
+/**
+ * Extracts the data from an AVPacket to a V4L2Buffer
+ *
+ * @param[in]  frame AVPacket to get the data from
+ * @param[in]  avbuf V4L2Bfuffer to push the information to
+ *
+ * @returns 0 in case of success, negative otherwise
+ */
+int ff_v4l2_buffer_avpkt_to_buf(const AVPacket *pkt, V4L2Buffer *out);
+
+/**
+ * Extracts the data from an AVFrame to a V4L2Buffer
+ *
+ * @param[in]  frame AVFrame to get the data from
+ * @param[in]  avbuf V4L2Bfuffer to push the information to
+ *
+ * @returns 0 in case of success, negative otherwise
+ */
+int ff_v4l2_buffer_avframe_to_buf(const AVFrame *frame, V4L2Buffer* out);
+
+/**
+ * Initializes a V4L2Buffer
+ *
+ * @param[in]  avbuf V4L2Bfuffer to initialize
+ * @param[in]  index v4l2 buffer id
+ *
+ * @returns 0 in case of success, negative otherwise
+ */
+int ff_v4l2_buffer_initialize(V4L2Buffer* avbuf, int index);
+
+/**
+ * Enqueues a V4L2Buffer
+ *
+ * @param[in] avbuf V4L2Bfuffer to push to the driver
+ *
+ * @returns 0 in case of success, negative otherwise
+ */
+int ff_v4l2_buffer_enqueue(V4L2Buffer* avbuf);
+
+
+#endif // AVCODEC_V4L2_BUFFERS_H
diff --git a/libavcodec/v4l2_context.c b/libavcodec/v4l2_context.c
new file mode 100644
index 0000000..1baaa5e
--- /dev/null
+++ b/libavcodec/v4l2_context.c
@@ -0,0 +1,638 @@ 
+/*
+ * V4L2 context helper functions.
+ *
+ * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
+ * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/videodev2.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <poll.h>
+#include "libavcodec/avcodec.h"
+#include "libavcodec/internal.h"
+#include "v4l2_buffers.h"
+#include "v4l2_fmt.h"
+#include "v4l2_m2m.h"
+
+struct v4l2_format_update {
+    uint32_t v4l2_fmt;
+    int update_v4l2;
+
+    enum AVPixelFormat av_fmt;
+    int update_avfmt;
+};
+
+static inline V4L2m2mContext *ctx_to_m2mctx(V4L2Context *ctx)
+{
+    return V4L2_TYPE_IS_OUTPUT(ctx->type) ?
+        container_of(ctx, V4L2m2mContext, output) :
+        container_of(ctx, V4L2m2mContext, capture);
+}
+
+static inline unsigned int v4l2_get_width(V4L2Context *ctx, struct v4l2_format *fmt)
+{
+    return V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ? fmt->fmt.pix_mp.width : fmt->fmt.pix.width;
+}
+
+static inline unsigned int v4l2_get_height(V4L2Context *ctx, struct v4l2_format *fmt)
+{
+    return V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ? fmt->fmt.pix_mp.height : fmt->fmt.pix.height;
+}
+
+static inline int v4l2_type_supported(V4L2Context *ctx)
+{
+    return ctx->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE ||
+        ctx->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE ||
+        ctx->type == V4L2_BUF_TYPE_VIDEO_CAPTURE ||
+        ctx->type == V4L2_BUF_TYPE_VIDEO_OUTPUT;
+}
+
+static inline void v4l2_save_to_context(V4L2Context* ctx, struct v4l2_format_update *fmt)
+{
+    ctx->format.type = ctx->type;
+
+    if (fmt->update_avfmt)
+        ctx->av_pix_fmt = fmt->av_fmt;
+
+    if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
+        /* update the sizes to handle the reconfiguration of the capture stream at runtime */
+        ctx->format.fmt.pix_mp.height = ctx->height;
+        ctx->format.fmt.pix_mp.width = ctx->width;
+        if (fmt->update_v4l2)
+            ctx->format.fmt.pix_mp.pixelformat = fmt->v4l2_fmt;
+
+    } else {
+        ctx->format.fmt.pix.height = ctx->height;
+        ctx->format.fmt.pix.width = ctx->width;
+        if (fmt->update_v4l2)
+            ctx->format.fmt.pix.pixelformat = fmt->v4l2_fmt;
+    }
+}
+
+static int v4l2_handle_event(V4L2Context *ctx)
+{
+    V4L2m2mContext *s = ctx_to_m2mctx(ctx);
+    struct v4l2_format cap_fmt = s->capture.format;
+    struct v4l2_format out_fmt = s->output.format;
+    struct v4l2_event evt;
+    int ret;
+
+    ret = ioctl(ctx->fd, VIDIOC_DQEVENT, &evt);
+    if (ret < 0) {
+        av_log(ctx->log_ctx, AV_LOG_ERROR, "%s VIDIOC_DQEVENT\n", ctx->name);
+        return 0;
+    }
+
+    ret = ioctl(s->fd, VIDIOC_G_FMT, &cap_fmt);
+    if (ret) {
+        av_log(s->capture.log_ctx, AV_LOG_ERROR, "%s VIDIOC_G_FMT\n", s->capture.name);
+        return 0;
+    }
+
+    ret = ioctl(s->fd, VIDIOC_G_FMT, &out_fmt);
+    if (ret) {
+        av_log(s->output.log_ctx, AV_LOG_ERROR, "%s VIDIOC_G_FMT\n", s->output.name);
+        return 0;
+    }
+
+    if (evt.type != V4L2_EVENT_SOURCE_CHANGE)
+        return 0;
+
+    if (v4l2_get_height(&s->output, &s->output.format) != v4l2_get_height(&s->output, &out_fmt) ||
+        v4l2_get_width(&s->output, &s->output.format) != v4l2_get_width(&s->output, &out_fmt)) {
+
+        av_log(s->output.log_ctx, AV_LOG_DEBUG, "%s changed (%dx%d) -> (%dx%d)\n",
+            s->output.name,
+            v4l2_get_width(&s->output, &s->output.format), v4l2_get_height(&s->output, &s->output.format),
+            v4l2_get_width(&s->output, &out_fmt), v4l2_get_height(&s->output, &out_fmt));
+
+        /* full reinit required to queue new output buffers since the current ones
+           are too small */
+        s->full_reinit = 1;
+
+        s->output.height = v4l2_get_height(ctx, &out_fmt);
+        s->output.width = v4l2_get_width(ctx, &out_fmt);
+    }
+
+    if (v4l2_get_height(&s->capture, &s->capture.format) != v4l2_get_height(&s->capture, &cap_fmt) ||
+        v4l2_get_width(&s->capture, &s->capture.format) != v4l2_get_width(&s->capture, &cap_fmt)) {
+
+        av_log(s->capture.log_ctx, AV_LOG_DEBUG, "%s changed (%dx%d) -> (%dx%d)\n",
+            s->capture.name,
+            v4l2_get_width(&s->capture, &s->capture.format), v4l2_get_height(&s->capture, &s->capture.format),
+            v4l2_get_width(&s->capture, &cap_fmt), v4l2_get_height(&s->capture, &cap_fmt));
+
+        s->capture.height = v4l2_get_height(ctx, &cap_fmt);
+        s->capture.width = v4l2_get_width(ctx, &cap_fmt);
+
+        /* streamoff capture and unmap and remap new capture buffers */
+        ret = ff_v4l2_m2m_codec_reinit(s);
+        if (ret)
+            av_log(ctx->log_ctx, AV_LOG_ERROR, "avpriv_v4l2m2m_reinit\n");
+
+        /* let the caller function know that reinit was executed */
+        return 1;
+    }
+
+    return 0;
+}
+
+static int v4l2_stop_decode(V4L2Context *ctx)
+{
+    struct v4l2_decoder_cmd cmd = {
+        .cmd = V4L2_DEC_CMD_STOP,
+    };
+    int ret;
+
+    ret = ioctl(ctx->fd, VIDIOC_DECODER_CMD, &cmd);
+    if (ret) {
+        /* DECODER_CMD is optional */
+        if (errno == ENOTTY)
+            return ff_v4l2_context_set_status(ctx, VIDIOC_STREAMOFF);
+    }
+
+    return 0;
+}
+
+static int v4l2_stop_encode(V4L2Context *ctx)
+{
+    struct v4l2_encoder_cmd cmd = {
+        .cmd = V4L2_ENC_CMD_STOP,
+    };
+    int ret;
+
+    ret = ioctl(ctx->fd, VIDIOC_ENCODER_CMD, &cmd);
+    if (ret) {
+        /* ENCODER_CMD is optional */
+        if (errno == ENOTTY)
+            return ff_v4l2_context_set_status(ctx, VIDIOC_STREAMOFF);
+    }
+
+    return 0;
+}
+
+static V4L2Buffer* v4l2_dequeue_v4l2buf(V4L2Context *ctx, int timeout)
+{
+    struct v4l2_plane planes[VIDEO_MAX_PLANES];
+    struct v4l2_buffer buf = { 0 };
+    V4L2Buffer* avbuf = NULL;
+    struct pollfd pfd = {
+        .events =  POLLIN | POLLRDNORM | POLLPRI | POLLOUT | POLLWRNORM, /* default blocking capture */
+        .fd = ctx->fd,
+    };
+    int ret;
+
+    if (V4L2_TYPE_IS_OUTPUT(ctx->type))
+        pfd.events =  POLLOUT | POLLWRNORM;
+
+    for (;;) {
+        ret = poll(&pfd, 1, timeout);
+        if (ret > 0)
+            break;
+        if (errno == EINTR)
+            continue;
+        return NULL;
+    }
+
+    /* 0. handle errors */
+    if (pfd.revents & POLLERR) {
+        av_log(ctx->log_ctx, AV_LOG_WARNING, "%s POLLERR\n", ctx->name);
+        return NULL;
+    }
+
+    /* 1. handle resolution changes */
+    if (pfd.revents & POLLPRI) {
+        ret = v4l2_handle_event(ctx);
+        if (ret) {
+            /* drop the buffer (if there was one) since we had to reconfigure capture (unmap all buffers) */
+            return NULL;
+        }
+    }
+
+    /* 2. dequeue the buffer */
+    if (pfd.revents & (POLLIN | POLLRDNORM | POLLOUT | POLLWRNORM)) {
+
+        if (!V4L2_TYPE_IS_OUTPUT(ctx->type)) {
+            /* there is a capture buffer ready */
+            if (pfd.revents & (POLLIN | POLLRDNORM))
+                goto dequeue;
+
+            /* the driver is ready to accept more input; instead of waiting for the capture
+             * buffer to complete we return NULL so input can proceed (we are single threaded)
+             */
+            if (pfd.revents & (POLLOUT | POLLWRNORM))
+                return NULL;
+        }
+
+dequeue:
+        memset(&buf, 0, sizeof(buf));
+        buf.memory = V4L2_MEMORY_MMAP;
+        buf.type = ctx->type;
+        if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
+            memset(planes, 0, sizeof(planes));
+            buf.length = VIDEO_MAX_PLANES;
+            buf.m.planes = planes;
+        }
+
+        ret = ioctl(ctx->fd, VIDIOC_DQBUF, &buf);
+        if (ret) {
+            if (errno != EAGAIN) {
+                ctx->done = errno;
+                if (errno != EPIPE)
+                    av_log(ctx->log_ctx, AV_LOG_DEBUG, "%s VIDIOC_DQBUF, errno (%s)\n",
+                        ctx->name, av_err2str(AVERROR(errno)));
+            }
+        } else {
+            avbuf = &ctx->buffers[buf.index];
+            avbuf->status = V4L2BUF_AVAILABLE;
+            avbuf->buf = buf;
+            if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
+                memcpy(avbuf->planes, planes, sizeof(planes));
+                avbuf->buf.m.planes = avbuf->planes;
+            }
+        }
+    }
+
+    return avbuf;
+}
+
+static V4L2Buffer* v4l2_getfree_v4l2buf(V4L2Context *ctx)
+{
+    int timeout = 0; /* return when no more buffers to dequeue */
+    int i;
+
+    /* get back as many output buffers as possible */
+    if (V4L2_TYPE_IS_OUTPUT(ctx->type)) {
+          do {
+          } while (v4l2_dequeue_v4l2buf(ctx, timeout));
+    }
+
+    for (i = 0; i < ctx->num_buffers; i++) {
+        if (ctx->buffers[i].status == V4L2BUF_AVAILABLE)
+            return &ctx->buffers[i];
+    }
+
+    return NULL;
+}
+
+static int v4l2_release_buffers(V4L2Context* ctx)
+{
+    struct v4l2_requestbuffers req = {
+        .memory = V4L2_MEMORY_MMAP,
+        .type = ctx->type,
+        .count = 0, /* 0 -> unmaps buffers from the driver */
+    };
+    int i, j;
+
+    for (i = 0; i < ctx->num_buffers; i++) {
+        V4L2Buffer *buffer = &ctx->buffers[i];
+
+        for (j = 0; j < buffer->num_planes; j++) {
+            struct V4L2Plane_info *p = &buffer->plane_info[j];
+            if (p->mm_addr && p->length)
+                if (munmap(p->mm_addr, p->length) < 0)
+                    av_log(ctx->log_ctx, AV_LOG_ERROR, "%s unmap plane (%s))\n", ctx->name, av_err2str(AVERROR(errno)));
+        }
+    }
+
+    return ioctl(ctx->fd, VIDIOC_REQBUFS, &req);
+}
+
+static inline int v4l2_try_raw_format(V4L2Context* ctx, enum AVPixelFormat pixfmt)
+{
+    struct v4l2_format *fmt = &ctx->format;
+    uint32_t v4l2_fmt;
+    int ret;
+
+    v4l2_fmt = ff_v4l2_format_avfmt_to_v4l2(pixfmt);
+    if (!v4l2_fmt)
+        return AVERROR(EINVAL);
+
+    if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type))
+        fmt->fmt.pix_mp.pixelformat = v4l2_fmt;
+    else
+        fmt->fmt.pix.pixelformat = v4l2_fmt;
+
+    fmt->type = ctx->type;
+
+    ret = ioctl(ctx->fd, VIDIOC_TRY_FMT, fmt);
+    if (ret)
+        return AVERROR(EINVAL);
+
+    return 0;
+}
+
+static int v4l2_query_raw_format(V4L2Context* ctx, enum AVPixelFormat *p)
+{
+    enum AVPixelFormat pixfmt = ctx->av_pix_fmt;
+    struct v4l2_fmtdesc fdesc;
+    int ret;
+
+    memset(&fdesc, 0, sizeof(fdesc));
+    fdesc.type = ctx->type;
+
+    if (pixfmt != AV_PIX_FMT_NONE) {
+        ret = v4l2_try_raw_format(ctx, pixfmt);
+        if (ret)
+            pixfmt = AV_PIX_FMT_NONE;
+        else
+            return 0;
+    }
+
+    for (;;) {
+        ret = ioctl(ctx->fd, VIDIOC_ENUM_FMT, &fdesc);
+        if (ret)
+            return AVERROR(EINVAL);
+
+        pixfmt = ff_v4l2_format_v4l2_to_avfmt(fdesc.pixelformat, AV_CODEC_ID_RAWVIDEO);
+        ret = v4l2_try_raw_format(ctx, pixfmt);
+        if (ret){
+            fdesc.index++;
+            continue;
+        }
+
+        *p = pixfmt;
+
+        return 0;
+    }
+
+    return AVERROR(EINVAL);
+}
+
+static int v4l2_query_coded_format(V4L2Context* ctx, uint32_t *p)
+{
+    struct v4l2_fmtdesc fdesc;
+    uint32_t v4l2_fmt;
+    int ret;
+
+    /* translate to a valid v4l2 format */
+    v4l2_fmt = ff_v4l2_format_avcodec_to_v4l2(ctx->av_codec_id);
+    if (!v4l2_fmt)
+        return AVERROR(EINVAL);
+
+    /* check if the driver supports this format */
+    memset(&fdesc, 0, sizeof(fdesc));
+    fdesc.type = ctx->type;
+
+    for (;;) {
+        ret = ioctl(ctx->fd, VIDIOC_ENUM_FMT, &fdesc);
+        if (ret)
+            return AVERROR(EINVAL);
+
+        if (fdesc.pixelformat == v4l2_fmt)
+            break;
+
+        fdesc.index++;
+    }
+
+    *p = v4l2_fmt;
+
+    return 0;
+}
+
+ /*****************************************************************************
+  *
+  *             V4L2 Context Interface
+  *
+  *****************************************************************************/
+
+int ff_v4l2_context_set_status(V4L2Context* ctx, int cmd)
+{
+    int type = ctx->type;
+    int ret;
+
+    ret = ioctl(ctx->fd, cmd, &type);
+    if (ret < 0)
+        return AVERROR(errno);
+
+    ctx->streamon = (cmd == VIDIOC_STREAMON);
+
+    return 0;
+}
+
+int ff_v4l2_context_enqueue_frame(V4L2Context* ctx, const AVFrame* frame)
+{
+    V4L2m2mContext *s = ctx_to_m2mctx(ctx);
+    V4L2Buffer* avbuf;
+    int ret;
+
+    if (!frame) {
+        ret = v4l2_stop_encode(ctx);
+        if (ret)
+            av_log(ctx->log_ctx, AV_LOG_ERROR, "%s stop_encode\n", ctx->name);
+        s->draining= 1;
+        return 0;
+    }
+
+    avbuf = v4l2_getfree_v4l2buf(ctx);
+    if (!avbuf)
+        return AVERROR(ENOMEM);
+
+    ret = ff_v4l2_buffer_avframe_to_buf(frame, avbuf);
+    if (ret)
+        return ret;
+
+    return ff_v4l2_buffer_enqueue(avbuf);
+}
+
+int ff_v4l2_context_enqueue_packet(V4L2Context* ctx, const AVPacket* pkt)
+{
+    V4L2m2mContext *s = ctx_to_m2mctx(ctx);
+    V4L2Buffer* avbuf;
+    int ret;
+
+    if (!pkt->size) {
+        ret = v4l2_stop_decode(ctx);
+        if (ret)
+            av_log(ctx->log_ctx, AV_LOG_ERROR, "%s stop_decode\n", ctx->name);
+        s->draining = 1;
+        return 0;
+    }
+
+    avbuf = v4l2_getfree_v4l2buf(ctx);
+    if (!avbuf)
+        return AVERROR(ENOMEM);
+
+    ret = ff_v4l2_buffer_avpkt_to_buf(pkt, avbuf);
+    if (ret)
+        return ret;
+
+    return ff_v4l2_buffer_enqueue(avbuf);
+}
+
+int ff_v4l2_context_dequeue_frame(V4L2Context* ctx, AVFrame* frame)
+{
+    V4L2Buffer* avbuf = NULL;
+
+    /* blocks until:
+     *  1. decoded frame available
+     *  2. an input buffer is ready to be dequeued
+     */
+    avbuf = v4l2_dequeue_v4l2buf(ctx, -1);
+    if (!avbuf) {
+        if (ctx->done)
+            return AVERROR_EOF;
+
+        return AVERROR(EAGAIN);
+    }
+
+    return ff_v4l2_buffer_buf_to_avframe(frame, avbuf);
+}
+
+int ff_v4l2_context_dequeue_packet(V4L2Context* ctx, AVPacket* pkt)
+{
+    V4L2Buffer* avbuf = NULL;
+
+    /* blocks until:
+     *  1. encoded packet available
+     *  2. an input buffer ready to be dequeued
+     */
+    avbuf = v4l2_dequeue_v4l2buf(ctx, -1);
+    if (!avbuf) {
+        if (ctx->done)
+            return AVERROR_EOF;
+
+        return AVERROR(EAGAIN);
+    }
+
+    return ff_v4l2_buffer_buf_to_avpkt(pkt, avbuf);
+}
+
+int ff_v4l2_context_query_format(V4L2Context* ctx)
+{
+    struct v4l2_format_update fmt = { 0 };
+    int ret;
+
+    if  (ctx->av_codec_id == AV_CODEC_ID_RAWVIDEO) {
+        ret = v4l2_query_raw_format(ctx, &fmt.av_fmt);
+        if (ret)
+            return ret;
+
+        /* no need to update fmt, only dimensions */
+        v4l2_save_to_context(ctx, &fmt);
+        return ret;
+    }
+
+    ret = v4l2_query_coded_format(ctx, &fmt.v4l2_fmt);
+    if (ret)
+        return ret;
+
+    /* update with the valid context we found and then try it */
+    fmt.update_v4l2 = 1;
+    v4l2_save_to_context(ctx, &fmt);
+
+    return ioctl(ctx->fd, VIDIOC_TRY_FMT, &ctx->format);
+}
+
+int ff_v4l2_context_set_format(V4L2Context* ctx)
+{
+    struct v4l2_format_update fmt = { 0 };
+    int ret;
+
+    if  (ctx->av_codec_id == AV_CODEC_ID_RAWVIDEO) {
+        ret = v4l2_query_raw_format(ctx, &fmt.av_fmt);
+        if (ret)
+            return ret;
+
+        /* update the valid context */
+        fmt.update_avfmt = 1;
+        v4l2_save_to_context(ctx, &fmt);
+
+        return ioctl(ctx->fd, VIDIOC_S_FMT, &ctx->format);
+    }
+
+    ret = v4l2_query_coded_format(ctx, &fmt.v4l2_fmt);
+    if (ret)
+        return ret;
+
+    /* update the valid context*/
+    fmt.update_v4l2 = 1;
+    v4l2_save_to_context(ctx, &fmt);
+
+    return ioctl(ctx->fd, VIDIOC_S_FMT, &ctx->format);
+}
+
+void ff_v4l2_context_release(V4L2Context* ctx)
+{
+    int ret;
+
+    if (!ctx->buffers)
+        return;
+
+    ret = v4l2_release_buffers(ctx);
+    if (ret)
+        av_log(ctx->log_ctx, AV_LOG_WARNING, "V4L2 failed to unmap the %s buffers\n", ctx->name);
+
+    av_free(ctx->buffers);
+    ctx->buffers = NULL;
+}
+
+int ff_v4l2_context_init(V4L2Context* ctx)
+{
+    V4L2m2mContext *s = ctx_to_m2mctx(ctx);
+    struct v4l2_requestbuffers req;
+    int ret, i;
+
+    if (!v4l2_type_supported(ctx)) {
+        av_log(ctx->log_ctx, AV_LOG_ERROR, "type %i not supported\n", ctx->type);
+        return AVERROR_PATCHWELCOME;
+    }
+
+    ret = ioctl(s->fd, VIDIOC_G_FMT, &ctx->format);
+    if (ret)
+        av_log(ctx->log_ctx, AV_LOG_ERROR, "%s VIDIOC_G_FMT failed\n", ctx->name);
+
+    memset(&req, 0, sizeof(req));
+    req.count = ctx->num_buffers;
+    req.memory = V4L2_MEMORY_MMAP;
+    req.type = ctx->type;
+    ret = ioctl(ctx->fd, VIDIOC_REQBUFS, &req);
+    if (ret < 0)
+        return AVERROR(errno);
+
+    ctx->num_buffers = req.count;
+    ctx->buffers = av_mallocz(ctx->num_buffers * sizeof(V4L2Buffer));
+    if (!ctx->buffers) {
+            av_log(ctx->log_ctx, AV_LOG_ERROR, "%s malloc enomem\n", ctx->name);
+            return AVERROR(ENOMEM);
+    }
+
+    for (i = 0; i < req.count; i++) {
+        ctx->buffers[i].context = ctx;
+        ret = ff_v4l2_buffer_initialize(&ctx->buffers[i], i);
+        if (ret < 0) {
+            av_log(ctx->log_ctx, AV_LOG_ERROR, "%s buffer initialization (%s)\n", ctx->name, av_err2str(ret));
+            av_free(ctx->buffers);
+            return ret;
+        }
+    }
+
+    av_log(ctx->log_ctx, AV_LOG_DEBUG, "%s: %s %02d buffers initialized: %04ux%04u, sizeimage %08u, bytesperline %08u\n", ctx->name,
+        V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ? av_fourcc2str(ctx->format.fmt.pix_mp.pixelformat) : av_fourcc2str(ctx->format.fmt.pix.pixelformat),
+        req.count,
+        V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ? ctx->format.fmt.pix_mp.width : ctx->format.fmt.pix.width,
+        V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ? ctx->format.fmt.pix_mp.height: ctx->format.fmt.pix.height,
+        V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ? ctx->format.fmt.pix_mp.plane_fmt[0].sizeimage : ctx->format.fmt.pix.sizeimage,
+        V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ? ctx->format.fmt.pix_mp.plane_fmt[0].bytesperline : ctx->format.fmt.pix.bytesperline);
+
+    return 0;
+}
diff --git a/libavcodec/v4l2_context.h b/libavcodec/v4l2_context.h
new file mode 100644
index 0000000..a08431e
--- /dev/null
+++ b/libavcodec/v4l2_context.h
@@ -0,0 +1,208 @@ 
+/*
+ * V4L2 context helper functions.
+ *
+ * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
+ * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_V4L2_CONTEXT_H
+#define AVCODEC_V4L2_CONTEXT_H
+
+#include <stdatomic.h>
+#include "libavcodec/avcodec.h"
+#include "libavutil/pixfmt.h"
+#include "libavutil/frame.h"
+#include "libavutil/buffer.h"
+#include "v4l2_buffers.h"
+
+typedef struct V4L2Context {
+
+    /**
+     * Log context
+     */
+    void *log_ctx;
+
+    /**
+     * context name: must be set before calling avpriv_v4l2_context_init().
+     */
+    const char* name;
+
+    /**
+     * File descriptor obtained from opening the associated device.
+     * Must be set before calling avpriv_v4l2_context_init().
+     * Readonly after init.
+     */
+    int fd;
+
+    /**
+     * Type of this buffer context.
+     * See V4L2_BUF_TYPE_VIDEO_* in videodev2.h
+     * Must be set before calling avpriv_v4l2_context_init().
+     * Readonly after init.
+     */
+    enum v4l2_buf_type type;
+
+    /**
+     * AVPixelFormat corresponding to this buffer context.
+     * AV_PIX_FMT_NONE means this is an encoded stream.
+     */
+    enum AVPixelFormat av_pix_fmt;
+
+    /**
+     * AVCodecID corresponding to this buffer context.
+     * AV_CODEC_ID_RAWVIDEO means this is a raw stream and av_pix_fmt must be set to a valid value.
+     */
+    enum AVCodecID av_codec_id;
+
+    /**
+     * Format returned by the driver after initializing the buffer context.
+     * Must be set before calling avpriv_v4l2_context_init().
+     * avpriv_v4l2m2m_format() can set it.
+     * Readonly after init.
+     */
+    struct v4l2_format format;
+
+    /**
+     * Width and height of the frames it produces (in case of a capture context, e.g. when decoding)
+     * or accepts (in case of an output context, e.g. when encoding).
+     *
+     * For output context, this must must be set before calling avpriv_v4l2_context_init().
+     * For capture context during decoding, it will be set after having received the
+     * information from the driver. at which point we can initialize the buffers.
+     */
+    int width, height;
+
+    /**
+     * Whether the stream has been started (VIDIOC_STREAMON has been sent).
+     */
+    int streamon;
+
+    /**
+     *
+     * Before calling avpriv_v4l2_context_init() this is the number of buffers we would like to have available.
+     * avpriv_v4l2_context_init() asks for (min_buffers + num_buffers) and sets this value to the actual number
+     * of buffers the driver gave us.
+     *
+     * Readonly after init.
+     */
+    int num_buffers;
+
+    /**
+     * Indexed array of V4L2Buffers
+     */
+    V4L2Buffer *buffers;
+
+    /**
+     *  Either no more buffers available or an unrecoverable error was notified
+     *  by the V4L2 kernel driver: once set the context has to be exited.
+     */
+    int done;
+
+} V4L2Context;
+
+/**
+ * Initializes a V4L2Context.
+ *
+ * @param[in] ctx A pointer to a V4L2Context. See V4L2Context description for required variables.
+ * @return 0 in case of success, a negative value representing the error otherwise.
+ */
+int ff_v4l2_context_init(V4L2Context* ctx);
+
+/**
+ * Set the selected format on a V4L2Context (used during driver init)
+ *
+ * @param[in] ctx A pointer to a V4L2Context. See V4L2Context description for required variables.
+ *
+ * @return 0 in case of success, a negative value representing the error otherwise.
+ */
+int ff_v4l2_context_set_format(V4L2Context* ctx);
+
+/**
+ * Queries the driver for a valid V4L2Context (used during driver probe)
+ *
+ * @param[in] ctx A pointer to a V4L2Context. See V4L2Context description for required variables.
+ *
+ * @return 0 in case of success, a negative value representing the error otherwise.
+ */
+int ff_v4l2_context_query_format(V4L2Context* ctx);
+
+/**
+ * Releases a V4L2Context.
+ *
+ * @param[in] ctx A pointer to a V4L2Context.
+ *               The caller is reponsible for freeing it.
+ *               It must not be used after calling this function.
+ */
+void ff_v4l2_context_release(V4L2Context* ctx);
+
+/**
+ * Sets the status of a V4L2Context.
+ *
+ * @param[in] ctx A pointer to a V4L2Context.
+ * @param[in] cmd The status to set (VIDIOC_STREAMON or VIDIOC_STREAMOFF).
+ *                Warning: If VIDIOC_STREAMOFF is sent to a buffer context that still has some frames buffered,
+ *                those frames will be dropped.
+ * @return 0 in case of success, a negative value representing the error otherwise.
+ */
+int ff_v4l2_context_set_status(V4L2Context* ctx, int cmd);
+
+/**
+ * Dequeues a buffer from a V4L2Context to an AVPacket.
+ *
+ * The pkt must be non NULL.
+ * @param[in] ctx The V4L2Context to dequeue from.
+ * @param[inout] pkt The AVPacket to dequeue to.
+ * @return 0 in case of success, AVERROR(EAGAIN) if no buffer was ready, another negative error in case of error.
+ */
+int ff_v4l2_context_dequeue_packet(V4L2Context* ctx, AVPacket* pkt);
+
+/**
+ * Dequeues a buffer from a V4L2Context to an AVFrame.
+ *
+ * The frame must be non NULL.
+ * @param[in] ctx The V4L2Context to dequeue from.
+ * @param[inout] f The AVFrame to dequeue to.
+ * @return 0 in case of success, AVERROR(EAGAIN) if no buffer was ready, another negative error in case of error.
+ */
+int ff_v4l2_context_dequeue_frame(V4L2Context* ctx, AVFrame* f);
+
+/**
+ * Enqueues a buffer to a V4L2Context from an AVPacket
+ *
+ * The packet must be non NULL.
+ * When the size of the pkt is null, the buffer is not queued but a V4L2_DEC_CMD_STOP command is sent instead to the driver.
+ *
+ * @param[in] ctx The V4L2Context to enqueue to.
+ * @param[in] pkt A pointer to an AVPacket.
+ * @return 0 in case of success, a negative error otherwise.
+ */
+int ff_v4l2_context_enqueue_packet(V4L2Context* ctx, const AVPacket* pkt);
+
+/**
+ * Enqueues a buffer to a V4L2Context from an AVFrame
+ *
+ * The frame must be non NULL.
+ *
+ * @param[in] ctx The V4L2Context to enqueue to.
+ * @param[in] f A pointer to an AVFrame to enqueue.
+ * @return 0 in case of success, a negative error otherwise.
+ */
+int ff_v4l2_context_enqueue_frame(V4L2Context* ctx, const AVFrame* f);
+
+#endif // AVCODEC_V4L2_CONTEXT_H
diff --git a/libavcodec/v4l2_fmt.c b/libavcodec/v4l2_fmt.c
new file mode 100644
index 0000000..a7ce308
--- /dev/null
+++ b/libavcodec/v4l2_fmt.c
@@ -0,0 +1,182 @@ 
+/*
+ * V4L2 format helper functions
+ *
+ * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
+ * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/videodev2.h>
+#include <search.h>
+#include "v4l2_fmt.h"
+
+#define V4L2_FMT(x) V4L2_PIX_FMT_##x
+#define AV_CODEC(x) AV_CODEC_ID_##x
+#define AV_FMT(x)   AV_PIX_FMT_##x
+
+static const struct fmt_conversion {
+    enum AVPixelFormat avfmt;
+    enum AVCodecID avcodec;
+    uint32_t v4l2_fmt;
+} fmt_map[] = {
+    { AV_FMT(RGB555LE),    AV_CODEC(RAWVIDEO),    V4L2_FMT(RGB555) },
+    { AV_FMT(RGB555BE),    AV_CODEC(RAWVIDEO),    V4L2_FMT(RGB555X) },
+    { AV_FMT(RGB565LE),    AV_CODEC(RAWVIDEO),    V4L2_FMT(RGB565) },
+    { AV_FMT(RGB565BE),    AV_CODEC(RAWVIDEO),    V4L2_FMT(RGB565X) },
+    { AV_FMT(BGR24),       AV_CODEC(RAWVIDEO),    V4L2_FMT(BGR24) },
+    { AV_FMT(RGB24),       AV_CODEC(RAWVIDEO),    V4L2_FMT(RGB24) },
+    { AV_FMT(BGR0),        AV_CODEC(RAWVIDEO),    V4L2_FMT(BGR32) },
+    { AV_FMT(0RGB),        AV_CODEC(RAWVIDEO),    V4L2_FMT(RGB32) },
+    { AV_FMT(GRAY8),       AV_CODEC(RAWVIDEO),    V4L2_FMT(GREY) },
+    { AV_FMT(YUV420P),     AV_CODEC(RAWVIDEO),    V4L2_FMT(YUV420) },
+    { AV_FMT(YUYV422),     AV_CODEC(RAWVIDEO),    V4L2_FMT(YUYV) },
+    { AV_FMT(UYVY422),     AV_CODEC(RAWVIDEO),    V4L2_FMT(UYVY) },
+    { AV_FMT(YUV422P),     AV_CODEC(RAWVIDEO),    V4L2_FMT(YUV422P) },
+    { AV_FMT(YUV411P),     AV_CODEC(RAWVIDEO),    V4L2_FMT(YUV411P) },
+    { AV_FMT(YUV410P),     AV_CODEC(RAWVIDEO),    V4L2_FMT(YUV410) },
+    { AV_FMT(YUV410P),     AV_CODEC(RAWVIDEO),    V4L2_FMT(YVU410) },
+    { AV_FMT(NV12),        AV_CODEC(RAWVIDEO),    V4L2_FMT(NV12) },
+    { AV_FMT(NONE),        AV_CODEC(MJPEG),       V4L2_FMT(MJPEG) },
+    { AV_FMT(NONE),        AV_CODEC(MJPEG),       V4L2_FMT(JPEG) },
+#ifdef V4L2_PIX_FMT_SRGGB8
+    { AV_FMT(BAYER_BGGR8), AV_CODEC(RAWVIDEO),    V4L2_FMT(SBGGR8) },
+    { AV_FMT(BAYER_GBRG8), AV_CODEC(RAWVIDEO),    V4L2_FMT(SGBRG8) },
+    { AV_FMT(BAYER_GRBG8), AV_CODEC(RAWVIDEO),    V4L2_FMT(SGRBG8) },
+    { AV_FMT(BAYER_RGGB8), AV_CODEC(RAWVIDEO),    V4L2_FMT(SRGGB8) },
+#endif
+#ifdef V4L2_PIX_FMT_Y16
+    { AV_FMT(GRAY16LE),    AV_CODEC(RAWVIDEO),    V4L2_FMT(Y16) },
+#endif
+#ifdef V4L2_PIX_FMT_NV12M
+    { AV_FMT(NV12),        AV_CODEC(RAWVIDEO),    V4L2_FMT(NV12M) },
+#endif
+#ifdef V4L2_PIX_FMT_NV21M
+    { AV_FMT(NV21),        AV_CODEC(RAWVIDEO),    V4L2_FMT(NV21M) },
+#endif
+#ifdef V4L2_PIX_FMT_YUV420M
+    { AV_FMT(YUV420P),     AV_CODEC(RAWVIDEO),    V4L2_FMT(YUV420M) },
+#endif
+#ifdef V4L2_PIX_FMT_NV16M
+    { AV_FMT(NV16),        AV_CODEC(RAWVIDEO),    V4L2_FMT(NV16M) },
+#endif
+#ifdef V4L2_PIX_FMT_H263
+    { AV_FMT(NONE),        AV_CODEC(H263),        V4L2_FMT(H263) },
+#endif
+#ifdef V4L2_PIX_FMT_H264
+    { AV_FMT(NONE),        AV_CODEC(H264),        V4L2_FMT(H264) },
+#endif
+#ifdef V4L2_PIX_FMT_MPEG4
+    { AV_FMT(NONE),        AV_CODEC(MPEG4),       V4L2_FMT(MPEG4) },
+#endif
+#ifdef V4L2_PIX_FMT_CPIA1
+    { AV_FMT(NONE),        AV_CODEC(CPIA),        V4L2_FMT(CPIA1) },
+#endif
+#ifdef V4L2_PIX_FMT_DV
+    { AV_FMT(NONE),        AV_CODEC(DVVIDEO),     V4L2_FMT(DV) },
+#endif
+#ifdef V4L2_PIX_FMT_MPEG1
+    { AV_FMT(NONE),        AV_CODEC(MPEG1VIDEO),  V4L2_FMT(MPEG1) },
+#endif
+#ifdef V4L2_PIX_FMT_MPEG2
+    { AV_FMT(NONE),        AV_CODEC(MPEG2VIDEO),  V4L2_FMT(MPEG2) },
+#endif
+#ifdef V4L2_PIX_FMT_VP8
+    { AV_FMT(NONE),        AV_CODEC(VP8),         V4L2_FMT(VP8) },
+#endif
+#ifdef V4L2_PIX_FMT_VP9
+    { AV_FMT(NONE),        AV_CODEC(VP9),         V4L2_FMT(VP9) },
+#endif
+#ifdef V4L2_PIX_FMT_HEVC
+    { AV_FMT(NONE),        AV_CODEC(HEVC),        V4L2_FMT(HEVC) },
+#endif
+#ifdef V4L2_PIX_FMT_VC1_ANNEX_G
+    { AV_FMT(NONE),        AV_CODEC(VC1),         V4L2_FMT(VC1_ANNEX_G) },
+#endif
+};
+
+static int match_codec(const void *a, const void *b)
+{
+    if (*(enum AVCodecID *)a == ((struct fmt_conversion *)b)->avcodec)
+        return 0;
+
+    return 1;
+}
+
+uint32_t ff_v4l2_format_avcodec_to_v4l2(enum AVCodecID avcodec)
+{
+    size_t len = FF_ARRAY_ELEMS(fmt_map);
+    struct fmt_conversion *item;
+
+    item = lfind(&avcodec, fmt_map, &len, sizeof(fmt_map[0]), match_codec);
+    if (item)
+        return item->v4l2_fmt;
+
+    return 0;
+}
+
+static int match_fmt(const void *a, const void *b)
+{
+    if ( *(enum AVPixelFormat *)a == ((struct fmt_conversion *)b)->avfmt)
+        return 0;
+
+    return 1;
+}
+
+uint32_t ff_v4l2_format_avfmt_to_v4l2(enum AVPixelFormat avfmt)
+{
+    size_t len = FF_ARRAY_ELEMS(fmt_map);
+    struct fmt_conversion *item;
+
+    item = lfind(&avfmt, fmt_map, &len, sizeof(fmt_map[0]), match_fmt);
+    if (item)
+        return item->v4l2_fmt;
+
+    return 0;
+}
+
+struct v4l2fmt_avcodec_pair {
+    enum AVCodecID avcodec;
+    uint32_t v4l2_fmt;
+};
+
+static int match_codecfmt(const void *a, const void *b)
+{
+    struct v4l2fmt_avcodec_pair *key = (struct v4l2fmt_avcodec_pair *) a;
+    struct fmt_conversion *item = (struct fmt_conversion *) b;
+
+    if (key->avcodec == item->avcodec && key->v4l2_fmt == item->v4l2_fmt)
+        return 0;
+
+    return 1;
+}
+
+enum AVPixelFormat ff_v4l2_format_v4l2_to_avfmt(uint32_t v4l2_fmt, enum AVCodecID avcodec)
+{
+    struct v4l2fmt_avcodec_pair const key = {
+        .v4l2_fmt = v4l2_fmt,
+        .avcodec = avcodec,
+    };
+    size_t len = FF_ARRAY_ELEMS(fmt_map);
+    struct fmt_conversion *item;
+
+    item = lfind(&key, fmt_map, &len, sizeof(fmt_map[0]), match_codecfmt);
+    if (item)
+        return item->avfmt;
+
+    return AV_PIX_FMT_NONE;
+}
diff --git a/libavcodec/v4l2_fmt.h b/libavcodec/v4l2_fmt.h
new file mode 100644
index 0000000..0136002
--- /dev/null
+++ b/libavcodec/v4l2_fmt.h
@@ -0,0 +1,34 @@ 
+/*
+ * V4L2 format helper functions
+ *
+ * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
+ * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_V4L2_FMT_H
+#define AVCODEC_V4L2_FMT_H
+
+#include "libavcodec/avcodec.h"
+#include "libavutil/pixfmt.h"
+
+enum AVPixelFormat ff_v4l2_format_v4l2_to_avfmt(uint32_t v4l2_fmt, enum AVCodecID avcodec);
+uint32_t ff_v4l2_format_avcodec_to_v4l2(enum AVCodecID avcodec);
+uint32_t ff_v4l2_format_avfmt_to_v4l2(enum AVPixelFormat avfmt);
+
+#endif /* AVCODEC_V4L2_FMT_H*/
diff --git a/libavcodec/v4l2_m2m.c b/libavcodec/v4l2_m2m.c
new file mode 100644
index 0000000..a2fc94c
--- /dev/null
+++ b/libavcodec/v4l2_m2m.c
@@ -0,0 +1,332 @@ 
+/*
+ * V4L mem2mem
+ *
+ * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
+ * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/videodev2.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include "libavcodec/avcodec.h"
+#include "libavcodec/internal.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/pixfmt.h"
+#include "v4l2_context.h"
+#include "v4l2_fmt.h"
+#include "v4l2_m2m.h"
+
+static inline int v4l2_splane_video(struct v4l2_capability *cap)
+{
+    if (cap->capabilities & (V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_VIDEO_OUTPUT) &&
+        cap->capabilities & V4L2_CAP_STREAMING)
+        return 1;
+
+    if (cap->capabilities & V4L2_CAP_VIDEO_M2M)
+        return 1;
+
+    return 0;
+}
+
+static inline int v4l2_mplane_video(struct v4l2_capability *cap)
+{
+    if (cap->capabilities & (V4L2_CAP_VIDEO_CAPTURE_MPLANE | V4L2_CAP_VIDEO_OUTPUT_MPLANE) &&
+        cap->capabilities & V4L2_CAP_STREAMING)
+        return 1;
+
+    if (cap->capabilities & V4L2_CAP_VIDEO_M2M_MPLANE)
+        return 1;
+
+    return 0;
+}
+
+static int v4l2_prepare_contexts(V4L2m2mContext* s)
+{
+    struct v4l2_capability cap;
+    int ret;
+
+    s->capture.log_ctx = s->output.log_ctx = s->avctx;;
+    s->capture.done = s->output.done = 0;
+    s->capture.fd = s->output.fd = s->fd;
+    s->capture.name = "capture";
+    s->output.name = "output ";
+    atomic_init(&s->refcount, 0);
+    sem_init(&s->refsync, 0, 0);
+
+    memset(&cap, 0, sizeof(cap));
+    ret = ioctl(s->fd, VIDIOC_QUERYCAP, &cap);
+    if (ret < 0)
+        return ret;
+
+    av_log(s->avctx, AV_LOG_INFO, "driver '%s' on card '%s'\n", cap.driver, cap.card);
+
+    if (v4l2_mplane_video(&cap)) {
+        s->capture.type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
+        s->output.type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
+        return 0;
+    }
+
+    if (v4l2_splane_video(&cap)) {
+        s->capture.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+        s->output.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+        return 0;
+    }
+
+    return AVERROR(EINVAL);
+}
+
+static int v4l2_probe_driver(V4L2m2mContext* s)
+{
+    int ret;
+
+    s->fd = open(s->devname, O_RDWR | O_NONBLOCK, 0);
+    if (s->fd < 0)
+        return AVERROR(errno);
+
+    ret = v4l2_prepare_contexts(s);
+    if (ret < 0)
+        goto done;
+
+    ret = ff_v4l2_context_query_format(&s->output);
+    if (ret) {
+        av_log(s->avctx, AV_LOG_DEBUG, "v4l2 output format not supported\n");
+        goto done;
+    }
+
+    ret = ff_v4l2_context_query_format(&s->capture);
+    if (ret) {
+        av_log(s->avctx, AV_LOG_DEBUG, "v4l2 capture format not supported\n");
+        goto done;
+    }
+
+done:
+    if (close(s->fd) < 0)
+        av_log(s->avctx, AV_LOG_ERROR, "failure closing %s (%s)\n", s->devname, av_err2str(AVERROR(errno)));
+
+    s->fd = -1;
+
+    return ret;
+}
+
+static int v4l2_configure_contexts(V4L2m2mContext* s)
+{
+    void *log_ctx = s->avctx;
+    int ret;
+
+    s->fd = open(s->devname, O_RDWR | O_NONBLOCK, 0);
+    if (s->fd < 0)
+        return AVERROR(errno);
+
+    ret = v4l2_prepare_contexts(s);
+    if (ret < 0)
+        goto error;
+
+    ret = ff_v4l2_context_set_format(&s->output);
+    if (ret) {
+        av_log(log_ctx, AV_LOG_ERROR, "can't set v4l2 output format\n");
+        goto error;
+    }
+
+    ret = ff_v4l2_context_set_format(&s->capture);
+    if (ret) {
+        av_log(log_ctx, AV_LOG_ERROR, "can't to set v4l2 capture format\n");
+        goto error;
+    }
+
+    ret = ff_v4l2_context_init(&s->output);
+    if (ret) {
+        av_log(log_ctx, AV_LOG_ERROR, "no v4l2 output context's buffers\n");
+        goto error;
+    }
+
+    /* decoder's buffers need to be updated at a later stage */
+    if (!av_codec_is_decoder(s->avctx->codec)) {
+        ret = ff_v4l2_context_init(&s->capture);
+        if (ret) {
+            av_log(log_ctx, AV_LOG_ERROR, "no v4l2 capture context's buffers\n");
+            goto error;
+        }
+    }
+
+    return 0;
+
+error:
+    if (close(s->fd) < 0)
+        av_log(log_ctx, AV_LOG_ERROR, "error closing %s (%s)\n",
+            s->devname, av_err2str(AVERROR(errno)));
+    s->fd = -1;
+
+    return ret;
+}
+
+/******************************************************************************
+ *
+ *                  V4L2 M2M Interface
+ *
+ ******************************************************************************/
+
+int ff_v4l2_m2m_codec_reinit(V4L2m2mContext* s)
+{
+    int ret;
+
+    if (s->full_reinit) {
+        av_log(s->avctx, AV_LOG_DEBUG, "%s full reinit\n", s->devname);
+
+        s->reinit = 1;
+        if (atomic_load(&s->refcount))
+            while(sem_wait(&s->refsync) == -1 && errno == EINTR);
+
+        /* close the driver */
+        ff_v4l2_m2m_codec_end(s->avctx);
+
+        /* start again now that we know the stream dimensions */
+        s->full_reinit = 0;
+        s->draining = 0;
+        s->reinit = 0;
+
+        ret = ff_v4l2_m2m_codec_init(s->avctx);
+        if (ret)
+            av_log(s->avctx, AV_LOG_ERROR, "%s full reinit failed\n", s->devname);
+
+        return 0;
+    }
+
+    /* 1. reinit in progress */
+    s->reinit = 1;
+
+    av_log(s->avctx, AV_LOG_DEBUG, "reinit context\n");
+
+    /* 2. streamoff */
+    ret = ff_v4l2_context_set_status(&s->capture, VIDIOC_STREAMOFF);
+    if (ret)
+        av_log(s->avctx, AV_LOG_ERROR, "capture VIDIOC_STREAMOFF\n");
+
+    /* 3. unmap the capture buffers (v4l2 and ffmpeg):
+     *    we must wait for all references to be released before being allowed
+     *    to queue new buffers.
+     */
+    av_log(s->avctx, AV_LOG_DEBUG, "waiting for user to release AVBufferRefs\n");
+    if (atomic_load(&s->refcount))
+        while(sem_wait(&s->refsync) == -1 && errno == EINTR);
+
+    ff_v4l2_context_release(&s->capture);
+
+    /* 4. sets the new capture format */
+    ret = ff_v4l2_context_set_format(&s->capture);
+    if (ret) {
+        av_log(s->avctx, AV_LOG_ERROR, "setting capture format\n");
+        return ret;
+    }
+
+    /* 5. update AVCodecContext */
+    ret = ff_set_dimensions(s->avctx, s->capture.width, s->capture.height);
+    if (ret < 0)
+        av_log(s->avctx, AV_LOG_WARNING, "update avcodec height and width\n");
+
+    /* 6. complete reinit */
+    sem_destroy(&s->refsync);
+    sem_init(&s->refsync, 0, 0);
+    s->draining = 0;
+    s->reinit = 0;
+
+    return 0;
+}
+
+int ff_v4l2_m2m_codec_end(AVCodecContext *avctx)
+{
+    V4L2m2mContext* s = avctx->priv_data;
+    int ret;
+
+    ret = ff_v4l2_context_set_status(&s->output, VIDIOC_STREAMOFF);
+    if (ret)
+            av_log(avctx, AV_LOG_ERROR, "VIDIOC_STREAMOFF %s\n", s->output.name);
+
+    ret = ff_v4l2_context_set_status(&s->capture, VIDIOC_STREAMOFF);
+    if (ret)
+        av_log(avctx, AV_LOG_ERROR, "VIDIOC_STREAMOFF %s\n", s->capture.name);
+
+    ff_v4l2_context_release(&s->output);
+
+    if (atomic_load(&s->refcount)) {
+        av_log(avctx, AV_LOG_DEBUG, "avpriv_v4l2m2m_end leaving pending buffers \n");
+
+        return 0;
+    }
+
+    ff_v4l2_context_release(&s->capture);
+    sem_destroy(&s->refsync);
+
+    /* release the hardware */
+    if (close(s->fd) < 0 )
+        av_log(avctx, AV_LOG_ERROR, "failure closing %s (%s)\n", s->devname, av_err2str(AVERROR(errno)));
+    s->fd = -1;
+
+    return 0;
+}
+
+int ff_v4l2_m2m_codec_init(AVCodecContext *avctx)
+{
+    int ret = AVERROR(EINVAL);
+    struct dirent *entry;
+    char node[PATH_MAX];
+    DIR *dirp;
+
+    V4L2m2mContext *s = avctx->priv_data;
+    s->avctx = avctx;
+
+    if (s->devname[0] != 0)
+        return v4l2_configure_contexts(s);
+
+    dirp = opendir("/dev");
+    if (!dirp)
+        return AVERROR(errno);
+
+    for (entry = readdir(dirp); entry; entry = readdir(dirp)) {
+
+        if (strncmp(entry->d_name, "video", 5))
+            continue;
+
+        snprintf(node, sizeof(node), "/dev/%s", entry->d_name);
+        av_log(s->avctx, AV_LOG_DEBUG, "probing device %s\n", node);
+        strncpy(s->devname, node, strlen(node) + 1);
+        ret = v4l2_probe_driver(s);
+        if (!ret)
+                break;
+    }
+
+    closedir(dirp);
+
+    if (ret) {
+        av_log(s->avctx, AV_LOG_ERROR, "Could not find a valid device\n");
+        memset(s->devname, 0, sizeof(s->devname));
+
+        return ret;
+    }
+
+    av_log(s->avctx, AV_LOG_INFO, "Using device %s\n", node);
+    ret = v4l2_configure_contexts(s);
+    if (ret)
+        memset(s->devname, 0, sizeof(s->devname));
+
+    return ret;
+}
diff --git a/libavcodec/v4l2_m2m.h b/libavcodec/v4l2_m2m.h
new file mode 100644
index 0000000..fb88f80
--- /dev/null
+++ b/libavcodec/v4l2_m2m.h
@@ -0,0 +1,94 @@ 
+/*
+ * V4L2 mem2mem helper functions
+ *
+ * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
+ * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_V4L2_M2M_H
+#define AVCODEC_V4L2_M2M_H
+
+#include <semaphore.h>
+#include <unistd.h>
+#include <dirent.h>
+#include "libavcodec/avcodec.h"
+#include "v4l2_context.h"
+
+#define container_of(ptr, type, member) ({ \
+        const __typeof__(((type *)0)->member ) *__mptr = (ptr); \
+        (type *)((char *)__mptr - offsetof(type,member) );})
+
+#define V4L_M2M_DEFAULT_OPTS \
+    { "num_output_buffers", "Number of buffers in the output context",\
+        OFFSET(output.num_buffers), AV_OPT_TYPE_INT, { .i64 = 16 }, 6, INT_MAX, FLAGS }
+
+typedef struct V4L2m2mContext
+{
+    AVClass *class;
+    char devname[PATH_MAX];
+    int fd;
+
+    /* the codec context queues */
+    V4L2Context capture;
+    V4L2Context output;
+
+    /* refcount of buffers held by the user */
+    atomic_uint refcount;
+
+    /* dynamic stream reconfig */
+    AVCodecContext *avctx;
+    sem_t refsync;
+    int full_reinit;
+    int reinit;
+
+    /* null frame/packet received */
+    int draining;
+} V4L2m2mContext;
+
+/**
+ * Probes the video nodes looking for the required codec capabilities.
+ *
+ * @param[in] ctx The AVCodecContext instantiated by the encoder/decoder.
+ *
+ * @returns 0 if a driver is found, a negative number otherwise.
+ */
+int ff_v4l2_m2m_codec_init(AVCodecContext *avctx);
+
+/**
+ * Releases all the codec resources if all AVBufferRefs have been returned to the
+ * ctx. Otherwise keep the driver open.
+ *
+ * @param[in] The AVCodecContext instantiated by the encoder/decoder.
+ *
+ * @returns 0
+ *
+ */
+int ff_v4l2_m2m_codec_end(AVCodecContext *avctx);
+
+/**
+ * Reinitializes the V4L2m2mContext when the driver cant continue processing
+ * with the  running parameters (ie, changes in format or resolution).
+ *
+ * @param[in] ctx The V4L2m2mContext instantiated by the encoder/decoder.
+ *
+ * @returns 0 in case of success, negative number otherwise
+ */
+int ff_v4l2_m2m_codec_reinit(V4L2m2mContext *ctx);
+
+#endif /* AVCODEC_V4L2_M2M_H */
diff --git a/libavcodec/v4l2_m2m_dec.c b/libavcodec/v4l2_m2m_dec.c
new file mode 100644
index 0000000..0cc930c
--- /dev/null
+++ b/libavcodec/v4l2_m2m_dec.c
@@ -0,0 +1,226 @@ 
+/*
+ * V4L2 mem2mem decoders
+ *
+ * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
+ * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/videodev2.h>
+#include <sys/ioctl.h>
+#include "libavutil/pixfmt.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/opt.h"
+#include "libavcodec/avcodec.h"
+#include "libavcodec/decode.h"
+
+#include "v4l2_context.h"
+#include "v4l2_m2m.h"
+#include "v4l2_fmt.h"
+
+static int v4l2_try_start(AVCodecContext *avctx)
+{
+    V4L2m2mContext *s = avctx->priv_data;
+    V4L2Context *const capture = &s->capture;
+    V4L2Context *const output = &s->output;
+    struct v4l2_selection selection;
+    int ret;
+
+    if (output->streamon && capture->streamon)
+        return 0;
+
+    /* 1. start the output process */
+    if (!output->streamon) {
+        ret = ff_v4l2_context_set_status(output, VIDIOC_STREAMON);
+        if (ret < 0) {
+            av_log(avctx, AV_LOG_DEBUG, "VIDIOC_STREAMON on output context\n");
+            return ret;
+        }
+    }
+
+    /* 2. get the capture format */
+    capture->format.type = capture->type;
+    ret = ioctl(capture->fd, VIDIOC_G_FMT, &capture->format);
+    if (ret) {
+        av_log(avctx, AV_LOG_WARNING, "VIDIOC_G_FMT ioctl\n");
+        return ret;
+    }
+
+    /* 2.1 update the AVCodecContext */
+    avctx->pix_fmt = ff_v4l2_format_v4l2_to_avfmt(capture->format.fmt.pix_mp.pixelformat, AV_CODEC_ID_RAWVIDEO);
+    capture->av_pix_fmt = avctx->pix_fmt;
+
+    /* 3. set the crop parameters */
+    selection.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    selection.r.height = avctx->coded_height;
+    selection.r.width = avctx->coded_width;
+    ret = ioctl(s->fd, VIDIOC_S_SELECTION, &selection);
+    if (!ret) {
+        ret = ioctl(s->fd, VIDIOC_G_SELECTION, &selection);
+        if (ret) {
+            av_log(avctx, AV_LOG_WARNING, "VIDIOC_G_SELECTION ioctl\n");
+        } else {
+            av_log(avctx, AV_LOG_DEBUG, "crop output %dx%d\n", selection.r.width, selection.r.height);
+            /* update the size of the resulting frame */
+            capture->height = selection.r.height;
+            capture->width  = selection.r.width;
+        }
+    }
+
+    /* 4. init the capture context now that we have the capture format */
+    if (!capture->buffers) {
+        ret = ff_v4l2_context_init(capture);
+        if (ret) {
+            av_log(avctx, AV_LOG_DEBUG, "can't request output buffers\n");
+            return ret;
+        }
+    }
+
+    /* 5. start the capture process */
+    ret = ff_v4l2_context_set_status(capture, VIDIOC_STREAMON);
+    if (ret) {
+        av_log(avctx, AV_LOG_DEBUG, "VIDIOC_STREAMON, on capture context\n");
+        return ret;
+    }
+
+    return 0;
+}
+
+static int v4l2_prepare_decoder(V4L2m2mContext *s)
+{
+    struct v4l2_event_subscription sub;
+    V4L2Context *output = &s->output;
+    int ret;
+
+    /**
+     * requirements
+     */
+    memset(&sub, 0, sizeof(sub));
+    sub.type = V4L2_EVENT_SOURCE_CHANGE;
+    ret = ioctl(s->fd, VIDIOC_SUBSCRIBE_EVENT, &sub);
+    if ( ret < 0) {
+        if (output->height == 0 || output->width == 0) {
+            av_log(s->avctx, AV_LOG_ERROR,
+                "the v4l2 driver does not support VIDIOC_SUBSCRIBE_EVENT\n"
+                "you must provide codec_height and codec_width on input\n");
+            return ret;
+        }
+    }
+
+    return 0;
+}
+
+static int v4l2_receive_frame(AVCodecContext *avctx, AVFrame *frame)
+{
+    V4L2m2mContext *s = avctx->priv_data;
+    V4L2Context *const capture = &s->capture;
+    V4L2Context *const output = &s->output;
+    AVPacket avpkt = {0};
+    int ret;
+
+    ret = ff_decode_get_packet(avctx, &avpkt);
+    if (ret < 0 && ret != AVERROR_EOF)
+        return ret;
+
+    if (s->draining)
+        goto dequeue;
+
+    ret = ff_v4l2_context_enqueue_packet(output, &avpkt);
+    if (ret < 0) {
+        if (ret != AVERROR(ENOMEM))
+           return ret;
+        /* no input buffers available, continue dequeing */
+    }
+
+    if (avpkt.size) {
+        ret = v4l2_try_start(avctx);
+        if (ret)
+            return 0;
+    }
+
+dequeue:
+    return ff_v4l2_context_dequeue_frame(capture, frame);
+}
+
+static av_cold int v4l2_decode_init(AVCodecContext *avctx)
+{
+    V4L2m2mContext *s = avctx->priv_data;
+    V4L2Context *capture = &s->capture;
+    V4L2Context *output = &s->output;
+    int ret;
+
+    /* if these dimensions are out of range, an event will be raised by the v4l2
+     * driver; this event will trigger a full pipeline reconfig and the proper
+     * values will be read from the driver
+     */
+    output->height = capture->height = avctx->coded_height;
+    output->width = capture->width = avctx->coded_width;
+
+    output->av_codec_id = avctx->codec_id;
+    output->av_pix_fmt  = AV_PIX_FMT_NONE;
+
+    capture->av_codec_id = AV_CODEC_ID_RAWVIDEO;
+    capture->av_pix_fmt = avctx->pix_fmt;
+
+    ret = ff_v4l2_m2m_codec_init(avctx);
+    if (ret)
+        return ret;
+
+    return v4l2_prepare_decoder(s);
+}
+
+#define OFFSET(x) offsetof(V4L2m2mContext, x)
+#define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM
+
+static const AVOption options[] = {
+    V4L_M2M_DEFAULT_OPTS,
+    { "num_capture_buffers", "Number of buffers in the capture context",
+        OFFSET(capture.num_buffers), AV_OPT_TYPE_INT, {.i64 = 20}, 20, INT_MAX, FLAGS },
+    { NULL},
+};
+
+#define M2MDEC(NAME, LONGNAME, CODEC, bsf_name) \
+static const AVClass v4l2_m2m_ ## NAME ## _dec_class = {\
+    .class_name = #NAME "_v4l2_m2m_decoder",\
+    .item_name  = av_default_item_name,\
+    .option     = options,\
+    .version    = LIBAVUTIL_VERSION_INT,\
+};\
+\
+AVCodec ff_ ## NAME ## _v4l2m2m_decoder = { \
+    .name           = #NAME "_v4l2m2m" ,\
+    .long_name      = NULL_IF_CONFIG_SMALL("V4L2 mem2mem " LONGNAME " decoder wrapper"),\
+    .type           = AVMEDIA_TYPE_VIDEO,\
+    .id             = CODEC ,\
+    .priv_data_size = sizeof(V4L2m2mContext),\
+    .priv_class     = &v4l2_m2m_ ## NAME ## _dec_class,\
+    .init           = v4l2_decode_init,\
+    .receive_frame  = v4l2_receive_frame,\
+    .close          = ff_v4l2_m2m_codec_end,\
+    .bsfs           = bsf_name, \
+};
+
+M2MDEC(h264,  "H.264", AV_CODEC_ID_H264,       "h264_mp4toannexb");
+M2MDEC(hevc,  "HEVC",  AV_CODEC_ID_HEVC,       "hevc_mp4toannexb");
+M2MDEC(mpeg1, "MPEG1", AV_CODEC_ID_MPEG1VIDEO, NULL);
+M2MDEC(mpeg2, "MPEG2", AV_CODEC_ID_MPEG2VIDEO, NULL);
+M2MDEC(mpeg4, "MPEG4", AV_CODEC_ID_MPEG4,      NULL);
+M2MDEC(h263,  "H.263", AV_CODEC_ID_H263,       NULL);
+M2MDEC(vc1 ,  "VC1",   AV_CODEC_ID_VC1,        NULL);
+M2MDEC(vp8,   "VP8",   AV_CODEC_ID_VP8,        NULL);
+M2MDEC(vp9,   "VP9",   AV_CODEC_ID_VP9,        NULL);
diff --git a/libavcodec/v4l2_m2m_enc.c b/libavcodec/v4l2_m2m_enc.c
new file mode 100644
index 0000000..9d1d303
--- /dev/null
+++ b/libavcodec/v4l2_m2m_enc.c
@@ -0,0 +1,350 @@ 
+/*
+ * V4L2 mem2mem encoders
+ *
+ * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
+ * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/videodev2.h>
+#include <sys/ioctl.h>
+#include <search.h>
+#include "libavcodec/avcodec.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/pixfmt.h"
+#include "libavutil/opt.h"
+#include "v4l2_context.h"
+#include "v4l2_m2m.h"
+
+#define MPEG_CID(x) V4L2_CID_MPEG_VIDEO_##x
+#define MPEG_VIDEO(x) V4L2_MPEG_VIDEO_##x
+
+static inline void v4l2_set_timeperframe(V4L2m2mContext *s, unsigned int num, unsigned int den)
+{
+    struct v4l2_streamparm parm = { 0 };
+
+    parm.type = V4L2_TYPE_IS_MULTIPLANAR(s->output.type) ? V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE : V4L2_BUF_TYPE_VIDEO_OUTPUT;
+    parm.parm.output.timeperframe.denominator = den;
+    parm.parm.output.timeperframe.numerator = num;
+
+    if (ioctl(s->fd, VIDIOC_S_PARM, &parm) < 0)
+        av_log(s->avctx, AV_LOG_WARNING, "Failed to set timeperframe");
+}
+
+static inline void v4l2_set_ext_ctrl(V4L2m2mContext *s, unsigned int id, signed int value, const char *name)
+{
+    struct v4l2_ext_controls ctrls = { 0 };
+    struct v4l2_ext_control ctrl = { 0 };
+
+    /* set ctrls */
+    ctrls.ctrl_class = V4L2_CTRL_CLASS_MPEG;
+    ctrls.controls = &ctrl;
+    ctrls.count = 1;
+
+    /* set ctrl*/
+    ctrl.value = value;
+    ctrl.id = id ;
+
+    if (ioctl(s->fd, VIDIOC_S_EXT_CTRLS, &ctrls) < 0)
+        av_log(s->avctx, AV_LOG_WARNING, "Failed to set %s\n", name);
+    else
+        av_log(s->avctx, AV_LOG_DEBUG, "Encoder: %s = %d\n", name, value);
+}
+
+static inline int v4l2_get_ext_ctrl(V4L2m2mContext *s, unsigned int id, signed int *value, const char *name)
+{
+    struct v4l2_ext_controls ctrls = { 0 };
+    struct v4l2_ext_control ctrl = { 0 };
+    int ret;
+
+    /* set ctrls */
+    ctrls.ctrl_class = V4L2_CTRL_CLASS_MPEG;
+    ctrls.controls = &ctrl;
+    ctrls.count = 1;
+
+    /* set ctrl*/
+    ctrl.id = id ;
+
+    ret = ioctl(s->fd, VIDIOC_G_EXT_CTRLS, &ctrls);
+    if (ret < 0) {
+        av_log(s->avctx, AV_LOG_WARNING, "Failed to set %s\n", name);
+        return ret;
+    }
+
+    *value = ctrl.value;
+
+    return 0;
+}
+
+static int match_profile(const void *a, const void *b)
+{
+    if (*(unsigned int *)a == *(unsigned int *)b)
+        return 0;
+
+    return 1;
+}
+
+static inline unsigned int v4l2_h264_profile_from_ff(int p)
+{
+    struct h264_profile  {
+        unsigned int ffmpeg_val;
+        unsigned int v4l2_val;
+    } *val, profile[] = {
+        { FF_PROFILE_H264_CONSTRAINED_BASELINE, MPEG_VIDEO(H264_PROFILE_CONSTRAINED_BASELINE) },
+        { FF_PROFILE_H264_HIGH_444_PREDICTIVE, MPEG_VIDEO(H264_PROFILE_HIGH_444_PREDICTIVE) },
+        { FF_PROFILE_H264_HIGH_422_INTRA, MPEG_VIDEO(H264_PROFILE_HIGH_422_INTRA) },
+        { FF_PROFILE_H264_HIGH_444_INTRA, MPEG_VIDEO(H264_PROFILE_HIGH_444_INTRA) },
+        { FF_PROFILE_H264_HIGH_10_INTRA, MPEG_VIDEO(H264_PROFILE_HIGH_10_INTRA) },
+        { FF_PROFILE_H264_HIGH_422, MPEG_VIDEO(H264_PROFILE_HIGH_422) },
+        { FF_PROFILE_H264_BASELINE, MPEG_VIDEO(H264_PROFILE_BASELINE) },
+        { FF_PROFILE_H264_EXTENDED, MPEG_VIDEO(H264_PROFILE_EXTENDED) },
+        { FF_PROFILE_H264_HIGH_10, MPEG_VIDEO(H264_PROFILE_HIGH_10) },
+        { FF_PROFILE_H264_MAIN, MPEG_VIDEO(H264_PROFILE_MAIN) },
+        { FF_PROFILE_H264_HIGH, MPEG_VIDEO(H264_PROFILE_HIGH) },
+    };
+    size_t len = FF_ARRAY_ELEMS(profile);
+
+    val = lfind(&p, profile, &len, sizeof(profile[0]), match_profile);
+    if (val)
+        return val->v4l2_val;
+
+    return AVERROR(ENOENT);
+}
+
+static inline int v4l2_mpeg4_profile_from_ff(int p)
+{
+    struct mpeg4_profile {
+        unsigned int ffmpeg_val;
+        unsigned int v4l2_val;
+    } *val, profile[] = {
+        { FF_PROFILE_MPEG4_ADVANCED_CODING, MPEG_VIDEO(MPEG4_PROFILE_ADVANCED_CODING_EFFICIENCY) },
+        { FF_PROFILE_MPEG4_ADVANCED_SIMPLE, MPEG_VIDEO(MPEG4_PROFILE_ADVANCED_SIMPLE) },
+        { FF_PROFILE_MPEG4_SIMPLE_SCALABLE, MPEG_VIDEO(MPEG4_PROFILE_SIMPLE_SCALABLE) },
+        { FF_PROFILE_MPEG4_SIMPLE, MPEG_VIDEO(MPEG4_PROFILE_SIMPLE) },
+        { FF_PROFILE_MPEG4_CORE, MPEG_VIDEO(MPEG4_PROFILE_CORE) },
+    };
+    size_t len = FF_ARRAY_ELEMS(profile);
+
+    val = lfind(&p, profile, &len, sizeof(profile[0]), match_profile);
+    if (val)
+        return val->v4l2_val;
+
+    return AVERROR(ENOENT);
+}
+
+static int v4l2_check_b_frame_support(V4L2m2mContext *s)
+{
+    if (s->avctx->max_b_frames)
+        av_log(s->avctx, AV_LOG_WARNING, "Encoder does not support b-frames yet\n");
+
+    v4l2_set_ext_ctrl(s, MPEG_CID(B_FRAMES), 0, "number of B-frames");
+    v4l2_get_ext_ctrl(s, MPEG_CID(B_FRAMES), &s->avctx->max_b_frames, "number of B-frames");
+    if (s->avctx->max_b_frames == 0)
+        return 0;
+
+    avpriv_report_missing_feature(s->avctx, "DTS/PTS calculation for V4L2 encoding");
+
+    return AVERROR_PATCHWELCOME;
+}
+
+static int v4l2_prepare_encoder(V4L2m2mContext *s)
+{
+    AVCodecContext *avctx = s->avctx;
+    int qmin_cid, qmax_cid, qmin, qmax;
+    int ret, val;
+
+    /**
+     * requirements
+     */
+    ret = v4l2_check_b_frame_support(s);
+    if (ret)
+        return ret;
+
+    /**
+     * settingss
+     */
+    if (avctx->framerate.num || avctx->framerate.den)
+        v4l2_set_timeperframe(s, avctx->framerate.num, avctx->framerate.den);
+
+    /* set ext ctrls */
+    v4l2_set_ext_ctrl(s, MPEG_CID(HEADER_MODE), MPEG_VIDEO(HEADER_MODE_SEPARATE), "header mode");
+    v4l2_set_ext_ctrl(s, MPEG_CID(BITRATE) , avctx->bit_rate, "bit rate");
+    v4l2_set_ext_ctrl(s, MPEG_CID(GOP_SIZE), avctx->gop_size,"gop size");
+
+    av_log(avctx, AV_LOG_DEBUG,
+        "Encoder Context: id (%d), profile (%d), frame rate(%d/%d), number b-frames (%d), "
+        "gop size (%d), bit rate (%ld), qmin (%d), qmax (%d)\n",
+        avctx->codec_id, avctx->profile, avctx->framerate.num, avctx->framerate.den,
+        avctx->max_b_frames, avctx->gop_size, avctx->bit_rate, avctx->qmin, avctx->qmax);
+
+    switch (avctx->codec_id) {
+    case AV_CODEC_ID_H264:
+        val = v4l2_h264_profile_from_ff(avctx->profile);
+        if (val < 0)
+            av_log(avctx, AV_LOG_WARNING, "h264 profile not found\n");
+        else
+            v4l2_set_ext_ctrl(s, MPEG_CID(H264_PROFILE), val, "h264 profile");
+        qmin_cid = MPEG_CID(H264_MIN_QP);
+        qmax_cid = MPEG_CID(H264_MAX_QP);
+        qmin = 0;
+        qmax = 51;
+        break;
+    case AV_CODEC_ID_MPEG4:
+        val = v4l2_mpeg4_profile_from_ff(avctx->profile);
+        if (val < 0)
+            av_log(avctx, AV_LOG_WARNING, "mpeg4 profile not found\n");
+        else
+            v4l2_set_ext_ctrl(s, MPEG_CID(MPEG4_PROFILE), val, "mpeg4 profile");
+        qmin_cid = MPEG_CID(MPEG4_MIN_QP);
+        qmax_cid = MPEG_CID(MPEG4_MAX_QP);
+        if (avctx->flags & CODEC_FLAG_QPEL)
+            v4l2_set_ext_ctrl(s, MPEG_CID(MPEG4_QPEL), 1, "qpel");
+        qmin = 1;
+        qmax = 31;
+        break;
+    case AV_CODEC_ID_H263:
+        qmin_cid = MPEG_CID(H263_MIN_QP);
+        qmax_cid = MPEG_CID(H263_MAX_QP);
+        qmin = 1;
+        qmax = 31;
+        break;
+    case AV_CODEC_ID_VP8:
+        qmin_cid = MPEG_CID(VPX_MIN_QP);
+        qmax_cid = MPEG_CID(VPX_MAX_QP);
+        qmin = 0;
+        qmax = 127;
+        break;
+    case AV_CODEC_ID_VP9:
+        qmin_cid = MPEG_CID(VPX_MIN_QP);
+        qmax_cid = MPEG_CID(VPX_MAX_QP);
+        qmin = 0;
+        qmax = 255;
+        break;
+    default:
+        return 0;
+    }
+
+    if (qmin != avctx->qmin || qmax != avctx->qmax)
+        av_log(avctx, AV_LOG_WARNING, "Encoder adjusted: qmin (%d), qmax (%d)\n", qmin, qmax);
+
+    v4l2_set_ext_ctrl(s, qmin_cid, qmin, "minimum video quantizer scale");
+    v4l2_set_ext_ctrl(s, qmax_cid, qmax, "maximum video quantizer scale");
+
+    return 0;
+}
+
+static int v4l2_send_frame(AVCodecContext *avctx, const AVFrame *frame)
+{
+    V4L2m2mContext *s = avctx->priv_data;
+    V4L2Context *const output = &s->output;
+
+    return ff_v4l2_context_enqueue_frame(output, frame);
+}
+
+static int v4l2_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
+{
+    V4L2m2mContext *s = avctx->priv_data;
+    V4L2Context *const capture = &s->capture;
+    V4L2Context *const output = &s->output;
+    int ret;
+
+    if (s->draining)
+        goto dequeue;
+
+    if (!output->streamon) {
+        ret = ff_v4l2_context_set_status(output, VIDIOC_STREAMON);
+        if (ret) {
+            av_log(avctx, AV_LOG_ERROR, "VIDIOC_STREAMOFF failed on output context\n");
+            return ret;
+        }
+    }
+
+    if (!capture->streamon) {
+        ret = ff_v4l2_context_set_status(capture, VIDIOC_STREAMON);
+        if (ret) {
+            av_log(avctx, AV_LOG_ERROR, "VIDIOC_STREAMON failed on capture context\n");
+            return ret;
+        }
+    }
+
+dequeue:
+    return ff_v4l2_context_dequeue_packet(capture, avpkt);
+}
+
+static av_cold int v4l2_encode_init(AVCodecContext *avctx)
+{
+    V4L2m2mContext *s = avctx->priv_data;
+    V4L2Context *capture = &s->capture;
+    V4L2Context *output = &s->output;
+    int ret;
+
+    /* common settings output/capture */
+    output->height = capture->height = avctx->height;
+    output->width = capture->width = avctx->width;
+
+    /* output context */
+    output->av_codec_id = AV_CODEC_ID_RAWVIDEO;
+    output->av_pix_fmt = avctx->pix_fmt;
+
+    /* capture context */
+    capture->av_codec_id = avctx->codec_id;
+    capture->av_pix_fmt = AV_PIX_FMT_NONE;
+
+    ret = ff_v4l2_m2m_codec_init(avctx);
+    if (ret)
+        return ret;
+
+    return v4l2_prepare_encoder(s);
+}
+
+#define OFFSET(x) offsetof(V4L2m2mContext, x)
+#define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
+
+static const AVOption options[] = {
+    V4L_M2M_DEFAULT_OPTS,
+    { "num_capture_buffers", "Number of buffers in the capture context",
+        OFFSET(capture.num_buffers), AV_OPT_TYPE_INT, {.i64 = 4 }, 4, INT_MAX, FLAGS },
+    { NULL },
+};
+
+#define M2MENC(NAME, LONGNAME, CODEC) \
+static const AVClass v4l2_m2m_ ## NAME ## _enc_class = {\
+    .class_name = #NAME "_v4l2_m2m_encoder",\
+    .item_name  = av_default_item_name,\
+    .option     = options,\
+    .version    = LIBAVUTIL_VERSION_INT,\
+};\
+\
+AVCodec ff_ ## NAME ## _v4l2m2m_encoder = { \
+    .name           = #NAME "_v4l2m2m" ,\
+    .long_name      = NULL_IF_CONFIG_SMALL("V4L2 mem2mem " LONGNAME " encoder wrapper"),\
+    .type           = AVMEDIA_TYPE_VIDEO,\
+    .id             = CODEC ,\
+    .priv_data_size = sizeof(V4L2m2mContext),\
+    .priv_class     = &v4l2_m2m_ ## NAME ##_enc_class,\
+    .init           = v4l2_encode_init,\
+    .send_frame     = v4l2_send_frame,\
+    .receive_packet = v4l2_receive_packet,\
+    .close          = ff_v4l2_m2m_codec_end,\
+};
+
+M2MENC(mpeg4,"MPEG4", AV_CODEC_ID_MPEG4);
+M2MENC(h263, "H.263", AV_CODEC_ID_H263);
+M2MENC(h264, "H.264", AV_CODEC_ID_H264);
+M2MENC(hevc, "HEVC",  AV_CODEC_ID_HEVC);
+M2MENC(vp8,  "VP8",   AV_CODEC_ID_VP8);