[FFmpeg-devel,6/7] avcodec: allow multiple hwaccels for the same codec/pixfmt

Submitted by wm4 on Oct. 3, 2017, 1:15 p.m.

Details

Message ID 20171003131518.4557-7-nfxjfg@googlemail.com
State New
Headers show

Commit Message

wm4 Oct. 3, 2017, 1:15 p.m.
Currently, AVHWAccels are looked up using a (codec_id, pixfmt) tuple.
This means it's impossible to have 2 decoders for the same codec and
using the same opaque hardware pixel format.

This breaks merging Libav's CUVID hwaccel. FFmpeg has its own CUVID
support, but it's a full stream decoder, using NVIDIA's codec parser.
The Libav one is a true hwaccel, which is based on the builtin software
decoders.

Fix this by introducing another field to disambiguate AVHWAccels, and
use it for our CUVID decoders. FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS makes
this mechanism backwards compatible and optional.
---
 libavcodec/Makefile   |  1 +
 libavcodec/avcodec.h  |  5 +++++
 libavcodec/cuviddec.c |  2 ++
 libavcodec/decode.c   | 12 ++++++++----
 libavcodec/internal.h |  5 +++++
 5 files changed, 21 insertions(+), 4 deletions(-)

Comments

Timo Rothenpieler Oct. 3, 2017, 1:58 p.m.
Am 03.10.2017 um 15:15 schrieb wm4:
> Currently, AVHWAccels are looked up using a (codec_id, pixfmt) tuple.
> This means it's impossible to have 2 decoders for the same codec and
> using the same opaque hardware pixel format.
> 
> This breaks merging Libav's CUVID hwaccel. FFmpeg has its own CUVID
> support, but it's a full stream decoder, using NVIDIA's codec parser.
> The Libav one is a true hwaccel, which is based on the builtin software
> decoders.
> 
> Fix this by introducing another field to disambiguate AVHWAccels, and
> use it for our CUVID decoders. FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS makes
> this mechanism backwards compatible and optional.
> ---
>   libavcodec/Makefile   |  1 +
>   libavcodec/avcodec.h  |  5 +++++
>   libavcodec/cuviddec.c |  2 ++
>   libavcodec/decode.c   | 12 ++++++++----
>   libavcodec/internal.h |  5 +++++
>   5 files changed, 21 insertions(+), 4 deletions(-)
> 
> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
> index fa3ab8f08a..3e0d654541 100644
> --- a/libavcodec/Makefile
> +++ b/libavcodec/Makefile
> @@ -820,6 +820,7 @@ OBJS-$(CONFIG_ADPCM_YAMAHA_DECODER)       += adpcm.o adpcm_data.o
>   OBJS-$(CONFIG_ADPCM_YAMAHA_ENCODER)       += adpcmenc.o adpcm_data.o
>   
>   # hardware accelerators
> +OBJS-$(CONFIG_CUVID)                      += cuvid.o
>   OBJS-$(CONFIG_D3D11VA)                    += dxva2.o
>   OBJS-$(CONFIG_DXVA2)                      += dxva2.o
>   OBJS-$(CONFIG_VAAPI)                      += vaapi_decode.o
> diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
> index 52cc5b0ca0..ecc49e5643 100644
> --- a/libavcodec/avcodec.h
> +++ b/libavcodec/avcodec.h
> @@ -4000,6 +4000,11 @@ typedef struct AVHWAccel {
>        * Internal hwaccel capabilities.
>        */
>       int caps_internal;
> +
> +    /**
> +     * Some hwaccels are ambiguous if only

This seems to be truncated?

> +     */
> +    const AVClass *decoder_class;
>   } AVHWAccel;
>   
>   /**
> diff --git a/libavcodec/cuviddec.c b/libavcodec/cuviddec.c
> index 2ba8e00c6a..6370348639 100644
> --- a/libavcodec/cuviddec.c
> +++ b/libavcodec/cuviddec.c
> @@ -1106,6 +1106,7 @@ static const AVOption options[] = {
>           .type           = AVMEDIA_TYPE_VIDEO, \
>           .id             = AV_CODEC_ID_##X, \
>           .pix_fmt        = AV_PIX_FMT_CUDA, \
> +        .decoder_class  = &x##_cuvid_class, \
>       }; \
>       AVCodec ff_##x##_cuvid_decoder = { \
>           .name           = #x "_cuvid", \
> @@ -1120,6 +1121,7 @@ static const AVOption options[] = {
>           .receive_frame  = cuvid_output_frame, \
>           .flush          = cuvid_flush, \
>           .capabilities   = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_AVOID_PROBING, \
> +        .caps_internal  = FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS, \
>           .pix_fmts       = (const enum AVPixelFormat[]){ AV_PIX_FMT_CUDA, \
>                                                           AV_PIX_FMT_NV12, \
>                                                           AV_PIX_FMT_P010, \
> diff --git a/libavcodec/decode.c b/libavcodec/decode.c
> index 668ef9667f..7060f6a3b7 100644
> --- a/libavcodec/decode.c
> +++ b/libavcodec/decode.c
> @@ -1152,15 +1152,19 @@ enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const en
>       return fmt[0];
>   }
>   
> -static AVHWAccel *find_hwaccel(enum AVCodecID codec_id,
> +static AVHWAccel *find_hwaccel(AVCodecContext *avctx,
>                                  enum AVPixelFormat pix_fmt)
>   {
>       AVHWAccel *hwaccel = NULL;
> +    const AVClass *av_class =
> +        (avctx->codec->caps_internal & FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS)
> +        ? avctx->av_class : NULL;
>   
> -    while ((hwaccel = av_hwaccel_next(hwaccel)))
> -        if (hwaccel->id == codec_id
> +    while ((hwaccel = av_hwaccel_next(hwaccel))) {
> +        if (hwaccel->decoder_class == av_class && hwaccel->id == avctx->codec_id
>               && hwaccel->pix_fmt == pix_fmt)
>               return hwaccel;
> +    }
>       return NULL;
>   }
>   
> @@ -1168,7 +1172,7 @@ static int setup_hwaccel(AVCodecContext *avctx,
>                            const enum AVPixelFormat fmt,
>                            const char *name)
>   {
> -    AVHWAccel *hwa = find_hwaccel(avctx->codec_id, fmt);
> +    AVHWAccel *hwa = find_hwaccel(avctx, fmt);
>       int ret        = 0;
>   
>       if (!hwa) {
> diff --git a/libavcodec/internal.h b/libavcodec/internal.h
> index faa923c11f..0177ea6521 100644
> --- a/libavcodec/internal.h
> +++ b/libavcodec/internal.h
> @@ -69,6 +69,11 @@
>    */
>   #define FF_CODEC_CAP_SLICE_THREAD_HAS_MF    (1 << 5)
>   
> +/**
> + * Allow only AVHWAccels which have a matching decoder_class field.
> + */
> +#define FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS  (1 << 6)
> +
>   #ifdef TRACE
>   #   define ff_tlog(ctx, ...) av_log(ctx, AV_LOG_TRACE, __VA_ARGS__)
>   #else
>
wm4 Oct. 3, 2017, 2:04 p.m.
On Tue, 3 Oct 2017 15:58:32 +0200
Timo Rothenpieler <timo@rothenpieler.org> wrote:

> Am 03.10.2017 um 15:15 schrieb wm4:
> > Currently, AVHWAccels are looked up using a (codec_id, pixfmt) tuple.
> > This means it's impossible to have 2 decoders for the same codec and
> > using the same opaque hardware pixel format.
> > 
> > This breaks merging Libav's CUVID hwaccel. FFmpeg has its own CUVID
> > support, but it's a full stream decoder, using NVIDIA's codec parser.
> > The Libav one is a true hwaccel, which is based on the builtin software
> > decoders.
> > 
> > Fix this by introducing another field to disambiguate AVHWAccels, and
> > use it for our CUVID decoders. FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS makes
> > this mechanism backwards compatible and optional.
> > ---
> >   libavcodec/Makefile   |  1 +
> >   libavcodec/avcodec.h  |  5 +++++
> >   libavcodec/cuviddec.c |  2 ++
> >   libavcodec/decode.c   | 12 ++++++++----
> >   libavcodec/internal.h |  5 +++++
> >   5 files changed, 21 insertions(+), 4 deletions(-)
> > 
> > diff --git a/libavcodec/Makefile b/libavcodec/Makefile
> > index fa3ab8f08a..3e0d654541 100644
> > --- a/libavcodec/Makefile
> > +++ b/libavcodec/Makefile
> > @@ -820,6 +820,7 @@ OBJS-$(CONFIG_ADPCM_YAMAHA_DECODER)       += adpcm.o adpcm_data.o
> >   OBJS-$(CONFIG_ADPCM_YAMAHA_ENCODER)       += adpcmenc.o adpcm_data.o
> >   
> >   # hardware accelerators
> > +OBJS-$(CONFIG_CUVID)                      += cuvid.o
> >   OBJS-$(CONFIG_D3D11VA)                    += dxva2.o
> >   OBJS-$(CONFIG_DXVA2)                      += dxva2.o
> >   OBJS-$(CONFIG_VAAPI)                      += vaapi_decode.o
> > diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
> > index 52cc5b0ca0..ecc49e5643 100644
> > --- a/libavcodec/avcodec.h
> > +++ b/libavcodec/avcodec.h
> > @@ -4000,6 +4000,11 @@ typedef struct AVHWAccel {
> >        * Internal hwaccel capabilities.
> >        */
> >       int caps_internal;
> > +
> > +    /**
> > +     * Some hwaccels are ambiguous if only  
> 
> This seems to be truncated?

Fixed locally with:

    /**
     * Some hwaccels are ambiguous if only the id and pix_fmt fields are used.
     * If non-NULL, the associated AVCodec must have
     * FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS set.
     */
    const AVClass *decoder_class;
Philip Langdale Oct. 3, 2017, 2:23 p.m.
On Tue,  3 Oct 2017 15:15:17 +0200
wm4 <nfxjfg@googlemail.com> wrote:

> Currently, AVHWAccels are looked up using a (codec_id, pixfmt) tuple.
> This means it's impossible to have 2 decoders for the same codec and
> using the same opaque hardware pixel format.
> 
> This breaks merging Libav's CUVID hwaccel. FFmpeg has its own CUVID
> support, but it's a full stream decoder, using NVIDIA's codec parser.
> The Libav one is a true hwaccel, which is based on the builtin
> software decoders.
> 
> Fix this by introducing another field to disambiguate AVHWAccels, and
> use it for our CUVID decoders. FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS
> makes this mechanism backwards compatible and optional.
> ---
>  libavcodec/Makefile   |  1 +
>  libavcodec/avcodec.h  |  5 +++++
>  libavcodec/cuviddec.c |  2 ++
>  libavcodec/decode.c   | 12 ++++++++----
>  libavcodec/internal.h |  5 +++++
>  5 files changed, 21 insertions(+), 4 deletions(-)
> 
> diff --git a/libavcodec/Makefile b/libavcodec/Makefile
> index fa3ab8f08a..3e0d654541 100644
> --- a/libavcodec/Makefile
> +++ b/libavcodec/Makefile
> @@ -820,6 +820,7 @@ OBJS-$(CONFIG_ADPCM_YAMAHA_DECODER)       +=
> adpcm.o adpcm_data.o OBJS-$(CONFIG_ADPCM_YAMAHA_ENCODER)       +=
> adpcmenc.o adpcm_data.o 
>  # hardware accelerators
> +OBJS-$(CONFIG_CUVID)                      += cuvid.o
>  OBJS-$(CONFIG_D3D11VA)                    += dxva2.o
>  OBJS-$(CONFIG_DXVA2)                      += dxva2.o
>  OBJS-$(CONFIG_VAAPI)                      += vaapi_decode.o
> diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
> index 52cc5b0ca0..ecc49e5643 100644
> --- a/libavcodec/avcodec.h
> +++ b/libavcodec/avcodec.h
> @@ -4000,6 +4000,11 @@ typedef struct AVHWAccel {
>       * Internal hwaccel capabilities.
>       */
>      int caps_internal;
> +
> +    /**
> +     * Some hwaccels are ambiguous if only
> +     */
> +    const AVClass *decoder_class;
>  } AVHWAccel;
>  
>  /**
> diff --git a/libavcodec/cuviddec.c b/libavcodec/cuviddec.c
> index 2ba8e00c6a..6370348639 100644
> --- a/libavcodec/cuviddec.c
> +++ b/libavcodec/cuviddec.c
> @@ -1106,6 +1106,7 @@ static const AVOption options[] = {
>          .type           = AVMEDIA_TYPE_VIDEO, \
>          .id             = AV_CODEC_ID_##X, \
>          .pix_fmt        = AV_PIX_FMT_CUDA, \
> +        .decoder_class  = &x##_cuvid_class, \
>      }; \
>      AVCodec ff_##x##_cuvid_decoder = { \
>          .name           = #x "_cuvid", \
> @@ -1120,6 +1121,7 @@ static const AVOption options[] = {
>          .receive_frame  = cuvid_output_frame, \
>          .flush          = cuvid_flush, \
>          .capabilities   = AV_CODEC_CAP_DELAY |
> AV_CODEC_CAP_AVOID_PROBING, \
> +        .caps_internal  = FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS, \
>          .pix_fmts       = (const enum
> AVPixelFormat[]){ AV_PIX_FMT_CUDA, \ AV_PIX_FMT_NV12, \
>                                                          AV_PIX_FMT_P010,
> \ diff --git a/libavcodec/decode.c b/libavcodec/decode.c
> index 668ef9667f..7060f6a3b7 100644
> --- a/libavcodec/decode.c
> +++ b/libavcodec/decode.c
> @@ -1152,15 +1152,19 @@ enum AVPixelFormat
> avcodec_default_get_format(struct AVCodecContext *s, const en return
> fmt[0]; }
>  
> -static AVHWAccel *find_hwaccel(enum AVCodecID codec_id,
> +static AVHWAccel *find_hwaccel(AVCodecContext *avctx,
>                                 enum AVPixelFormat pix_fmt)
>  {
>      AVHWAccel *hwaccel = NULL;
> +    const AVClass *av_class =
> +        (avctx->codec->caps_internal &
> FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS)
> +        ? avctx->av_class : NULL;
>  
> -    while ((hwaccel = av_hwaccel_next(hwaccel)))
> -        if (hwaccel->id == codec_id
> +    while ((hwaccel = av_hwaccel_next(hwaccel))) {
> +        if (hwaccel->decoder_class == av_class && hwaccel->id ==
> avctx->codec_id && hwaccel->pix_fmt == pix_fmt)
>              return hwaccel;
> +    }
>      return NULL;
>  }
>  
> @@ -1168,7 +1172,7 @@ static int setup_hwaccel(AVCodecContext *avctx,
>                           const enum AVPixelFormat fmt,
>                           const char *name)
>  {
> -    AVHWAccel *hwa = find_hwaccel(avctx->codec_id, fmt);
> +    AVHWAccel *hwa = find_hwaccel(avctx, fmt);
>      int ret        = 0;
>  
>      if (!hwa) {
> diff --git a/libavcodec/internal.h b/libavcodec/internal.h
> index faa923c11f..0177ea6521 100644
> --- a/libavcodec/internal.h
> +++ b/libavcodec/internal.h
> @@ -69,6 +69,11 @@
>   */
>  #define FF_CODEC_CAP_SLICE_THREAD_HAS_MF    (1 << 5)
>  
> +/**
> + * Allow only AVHWAccels which have a matching decoder_class field.
> + */
> +#define FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS  (1 << 6)
> +
>  #ifdef TRACE
>  #   define ff_tlog(ctx, ...) av_log(ctx, AV_LOG_TRACE, __VA_ARGS__)
>  #else

Looks fine. Nothing beyond what Timo said.


--phil
wm4 Oct. 3, 2017, 4 p.m.
On Tue, 3 Oct 2017 15:58:32 +0200
Timo Rothenpieler <timo@rothenpieler.org> wrote:

> > -static AVHWAccel *find_hwaccel(enum AVCodecID codec_id,
> > +static AVHWAccel *find_hwaccel(AVCodecContext *avctx,
> >                                  enum AVPixelFormat pix_fmt)
> >   {
> >       AVHWAccel *hwaccel = NULL;
> > +    const AVClass *av_class =
> > +        (avctx->codec->caps_internal & FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS)
> > +        ? avctx->av_class : NULL;

Also this is actually completely broken. It's trivially fixed, but if
anyone actually wants to try the patches, here's an updated set:

https://github.com/wm4/FFmpeg/tree/libav-cuvid

Patch hide | download patch | download mbox

diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index fa3ab8f08a..3e0d654541 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -820,6 +820,7 @@  OBJS-$(CONFIG_ADPCM_YAMAHA_DECODER)       += adpcm.o adpcm_data.o
 OBJS-$(CONFIG_ADPCM_YAMAHA_ENCODER)       += adpcmenc.o adpcm_data.o
 
 # hardware accelerators
+OBJS-$(CONFIG_CUVID)                      += cuvid.o
 OBJS-$(CONFIG_D3D11VA)                    += dxva2.o
 OBJS-$(CONFIG_DXVA2)                      += dxva2.o
 OBJS-$(CONFIG_VAAPI)                      += vaapi_decode.o
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 52cc5b0ca0..ecc49e5643 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -4000,6 +4000,11 @@  typedef struct AVHWAccel {
      * Internal hwaccel capabilities.
      */
     int caps_internal;
+
+    /**
+     * Some hwaccels are ambiguous if only
+     */
+    const AVClass *decoder_class;
 } AVHWAccel;
 
 /**
diff --git a/libavcodec/cuviddec.c b/libavcodec/cuviddec.c
index 2ba8e00c6a..6370348639 100644
--- a/libavcodec/cuviddec.c
+++ b/libavcodec/cuviddec.c
@@ -1106,6 +1106,7 @@  static const AVOption options[] = {
         .type           = AVMEDIA_TYPE_VIDEO, \
         .id             = AV_CODEC_ID_##X, \
         .pix_fmt        = AV_PIX_FMT_CUDA, \
+        .decoder_class  = &x##_cuvid_class, \
     }; \
     AVCodec ff_##x##_cuvid_decoder = { \
         .name           = #x "_cuvid", \
@@ -1120,6 +1121,7 @@  static const AVOption options[] = {
         .receive_frame  = cuvid_output_frame, \
         .flush          = cuvid_flush, \
         .capabilities   = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_AVOID_PROBING, \
+        .caps_internal  = FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS, \
         .pix_fmts       = (const enum AVPixelFormat[]){ AV_PIX_FMT_CUDA, \
                                                         AV_PIX_FMT_NV12, \
                                                         AV_PIX_FMT_P010, \
diff --git a/libavcodec/decode.c b/libavcodec/decode.c
index 668ef9667f..7060f6a3b7 100644
--- a/libavcodec/decode.c
+++ b/libavcodec/decode.c
@@ -1152,15 +1152,19 @@  enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const en
     return fmt[0];
 }
 
-static AVHWAccel *find_hwaccel(enum AVCodecID codec_id,
+static AVHWAccel *find_hwaccel(AVCodecContext *avctx,
                                enum AVPixelFormat pix_fmt)
 {
     AVHWAccel *hwaccel = NULL;
+    const AVClass *av_class =
+        (avctx->codec->caps_internal & FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS)
+        ? avctx->av_class : NULL;
 
-    while ((hwaccel = av_hwaccel_next(hwaccel)))
-        if (hwaccel->id == codec_id
+    while ((hwaccel = av_hwaccel_next(hwaccel))) {
+        if (hwaccel->decoder_class == av_class && hwaccel->id == avctx->codec_id
             && hwaccel->pix_fmt == pix_fmt)
             return hwaccel;
+    }
     return NULL;
 }
 
@@ -1168,7 +1172,7 @@  static int setup_hwaccel(AVCodecContext *avctx,
                          const enum AVPixelFormat fmt,
                          const char *name)
 {
-    AVHWAccel *hwa = find_hwaccel(avctx->codec_id, fmt);
+    AVHWAccel *hwa = find_hwaccel(avctx, fmt);
     int ret        = 0;
 
     if (!hwa) {
diff --git a/libavcodec/internal.h b/libavcodec/internal.h
index faa923c11f..0177ea6521 100644
--- a/libavcodec/internal.h
+++ b/libavcodec/internal.h
@@ -69,6 +69,11 @@ 
  */
 #define FF_CODEC_CAP_SLICE_THREAD_HAS_MF    (1 << 5)
 
+/**
+ * Allow only AVHWAccels which have a matching decoder_class field.
+ */
+#define FF_CODEC_CAP_HWACCEL_REQUIRE_CLASS  (1 << 6)
+
 #ifdef TRACE
 #   define ff_tlog(ctx, ...) av_log(ctx, AV_LOG_TRACE, __VA_ARGS__)
 #else