diff mbox

[FFmpeg-devel,v1] avfilter/vf_freezedetect: add metadata lavfi.freezedetect.mafd

Message ID 20191010034840.1736-1-lance.lmwang@gmail.com
State New
Headers show

Commit Message

Limin Wang Oct. 10, 2019, 3:48 a.m. UTC
From: Limin Wang <lance.lmwang@gmail.com>

As suggested by Paul to support frozen frames discard, please refer to:
https://patchwork.ffmpeg.org/patch/15423/

You can tested with below commands:

./ffmpeg  -f lavfi -i "smptebars=duration=5:size=1280x720:rate=30,freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.01:function=greater"  -f null -
frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.03 bitrate=N/A speed=2.14x

Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
---
 doc/filters.texi              | 9 +++++++++
 libavfilter/vf_freezedetect.c | 7 +++++++
 2 files changed, 16 insertions(+)

Comments

Limin Wang Oct. 23, 2019, 10:12 a.m. UTC | #1
ping, it's another approach to discard frozen frame, please comments.


On Thu, Oct 10, 2019 at 11:48:40AM +0800, lance.lmwang@gmail.com wrote:
> From: Limin Wang <lance.lmwang@gmail.com>
> 
> As suggested by Paul to support frozen frames discard, please refer to:
> https://patchwork.ffmpeg.org/patch/15423/
> 
> You can tested with below commands:
> 
> ./ffmpeg  -f lavfi -i "smptebars=duration=5:size=1280x720:rate=30,freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.01:function=greater"  -f null -
> frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.03 bitrate=N/A speed=2.14x
> 
> Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
> ---
>  doc/filters.texi              | 9 +++++++++
>  libavfilter/vf_freezedetect.c | 7 +++++++
>  2 files changed, 16 insertions(+)
> 
> diff --git a/doc/filters.texi b/doc/filters.texi
> index 55a8ebae56..cfc10c8479 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -10800,6 +10800,15 @@ timestamp of the first frame of the freeze. The
>  @code{lavfi.freezedetect.freeze_end} metadata keys are set on the first frame
>  after the freeze.
>  
> +The @code{lavfi.freezedetect.mafd} metadata key is set for all frames except the
> +first reference frame. You can use it to drop frozen frames by metadata select
> +mode. Note that in this way the first few frozen frames(the detection interval)
> +are dropped also. An example is as follows:
> +@example
> +freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.001:function=greater
> +@end example
> +
> +
>  The filter accepts the following options:
>  
>  @table @option
> diff --git a/libavfilter/vf_freezedetect.c b/libavfilter/vf_freezedetect.c
> index cc086afee6..3931bcfa2e 100644
> --- a/libavfilter/vf_freezedetect.c
> +++ b/libavfilter/vf_freezedetect.c
> @@ -124,11 +124,14 @@ static av_cold void uninit(AVFilterContext *ctx)
>      av_frame_free(&s->reference_frame);
>  }
>  
> +static int set_meta(FreezeDetectContext *s, AVFrame *frame, const char *key, const char *value);
>  static int is_frozen(FreezeDetectContext *s, AVFrame *reference, AVFrame *frame)
>  {
>      uint64_t sad = 0;
>      uint64_t count = 0;
>      double mafd;
> +    char buf[64];
> +
>      for (int plane = 0; plane < 4; plane++) {
>          if (s->width[plane]) {
>              uint64_t plane_sad;
> @@ -141,6 +144,10 @@ static int is_frozen(FreezeDetectContext *s, AVFrame *reference, AVFrame *frame)
>      }
>      emms_c();
>      mafd = (double)sad / count / (1ULL << s->bitdepth);
> +
> +    snprintf(buf, sizeof(buf), "%0.5f", mafd);
> +    set_meta(s, frame, "lavfi.freezedetect.mafd", buf);
> +
>      return (mafd <= s->noise);
>  }
>  
> -- 
> 2.21.0
>
Paul B Mahol Oct. 23, 2019, 10:23 a.m. UTC | #2
lgtm

On 10/10/19, lance.lmwang@gmail.com <lance.lmwang@gmail.com> wrote:
> From: Limin Wang <lance.lmwang@gmail.com>
>
> As suggested by Paul to support frozen frames discard, please refer to:
> https://patchwork.ffmpeg.org/patch/15423/
>
> You can tested with below commands:
>
> ./ffmpeg  -f lavfi -i
> "smptebars=duration=5:size=1280x720:rate=30,freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.01:function=greater"
>  -f null -
> frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.03 bitrate=N/A
> speed=2.14x
>
> Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
> ---
>  doc/filters.texi              | 9 +++++++++
>  libavfilter/vf_freezedetect.c | 7 +++++++
>  2 files changed, 16 insertions(+)
>
> diff --git a/doc/filters.texi b/doc/filters.texi
> index 55a8ebae56..cfc10c8479 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -10800,6 +10800,15 @@ timestamp of the first frame of the freeze. The
>  @code{lavfi.freezedetect.freeze_end} metadata keys are set on the first
> frame
>  after the freeze.
>
> +The @code{lavfi.freezedetect.mafd} metadata key is set for all frames
> except the
> +first reference frame. You can use it to drop frozen frames by metadata
> select
> +mode. Note that in this way the first few frozen frames(the detection
> interval)
> +are dropped also. An example is as follows:
> +@example
> +freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.001:function=greater
> +@end example
> +
> +
>  The filter accepts the following options:
>
>  @table @option
> diff --git a/libavfilter/vf_freezedetect.c b/libavfilter/vf_freezedetect.c
> index cc086afee6..3931bcfa2e 100644
> --- a/libavfilter/vf_freezedetect.c
> +++ b/libavfilter/vf_freezedetect.c
> @@ -124,11 +124,14 @@ static av_cold void uninit(AVFilterContext *ctx)
>      av_frame_free(&s->reference_frame);
>  }
>
> +static int set_meta(FreezeDetectContext *s, AVFrame *frame, const char
> *key, const char *value);
>  static int is_frozen(FreezeDetectContext *s, AVFrame *reference, AVFrame
> *frame)
>  {
>      uint64_t sad = 0;
>      uint64_t count = 0;
>      double mafd;
> +    char buf[64];
> +
>      for (int plane = 0; plane < 4; plane++) {
>          if (s->width[plane]) {
>              uint64_t plane_sad;
> @@ -141,6 +144,10 @@ static int is_frozen(FreezeDetectContext *s, AVFrame
> *reference, AVFrame *frame)
>      }
>      emms_c();
>      mafd = (double)sad / count / (1ULL << s->bitdepth);
> +
> +    snprintf(buf, sizeof(buf), "%0.5f", mafd);
> +    set_meta(s, frame, "lavfi.freezedetect.mafd", buf);
> +
>      return (mafd <= s->noise);
>  }
>
> --
> 2.21.0
>
> _______________________________________________
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> ffmpeg-devel@ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
Marton Balint Oct. 23, 2019, 12:32 p.m. UTC | #3
On Wed, 23 Oct 2019, Limin Wang wrote:

>
>
> ping, it's another approach to discard frozen frame, please comments.
>
>
> On Thu, Oct 10, 2019 at 11:48:40AM +0800, lance.lmwang@gmail.com wrote:
>> From: Limin Wang <lance.lmwang@gmail.com>
>> 
>> As suggested by Paul to support frozen frames discard, please refer to:
>> https://patchwork.ffmpeg.org/patch/15423/
>> 
>> You can tested with below commands:
>> 
>> ./ffmpeg  -f lavfi -i "smptebars=duration=5:size=1280x720:rate=30,freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.01:function=greater"  -f null -
>> frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.03 bitrate=N/A speed=2.14x
>> 
>> Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
>> ---
>>  doc/filters.texi              | 9 +++++++++
>>  libavfilter/vf_freezedetect.c | 7 +++++++
>>  2 files changed, 16 insertions(+)
>> 
>> diff --git a/doc/filters.texi b/doc/filters.texi
>> index 55a8ebae56..cfc10c8479 100644
>> --- a/doc/filters.texi
>> +++ b/doc/filters.texi
>> @@ -10800,6 +10800,15 @@ timestamp of the first frame of the freeze. The
>>  @code{lavfi.freezedetect.freeze_end} metadata keys are set on the first frame
>>  after the freeze.
>> 
>> +The @code{lavfi.freezedetect.mafd} metadata key is set for all frames except the
>> +first reference frame. You can use it to drop frozen frames by metadata select
>> +mode. Note that in this way the first few frozen frames(the detection interval)
>> +are dropped also. An example is as follows:
>> +@example
>> +freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.001:function=greater
>> +@end example

No, this is not what this is. This way you drop in the detection interval 
even if no freeze is detected. So this approach is only slightly 
different to selecting a very small (less than a frame) detection interval.

So I don't see the point of this patch.

Regards,
Marton
Limin Wang Oct. 23, 2019, 2:31 p.m. UTC | #4
On Wed, Oct 23, 2019 at 02:32:54PM +0200, Marton Balint wrote:
> 
> 
> On Wed, 23 Oct 2019, Limin Wang wrote:
> 
> >
> >
> >ping, it's another approach to discard frozen frame, please comments.
> >
> >
> >On Thu, Oct 10, 2019 at 11:48:40AM +0800, lance.lmwang@gmail.com wrote:
> >>From: Limin Wang <lance.lmwang@gmail.com>
> >>
> >>As suggested by Paul to support frozen frames discard, please refer to:
> >>https://patchwork.ffmpeg.org/patch/15423/
> >>
> >>You can tested with below commands:
> >>
> >>./ffmpeg  -f lavfi -i "smptebars=duration=5:size=1280x720:rate=30,freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.01:function=greater"  -f null -
> >>frame=    1 fps=0.0 q=-0.0 Lsize=N/A time=00:00:00.03 bitrate=N/A speed=2.14x
> >>
> >>Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
> >>---
> >> doc/filters.texi              | 9 +++++++++
> >> libavfilter/vf_freezedetect.c | 7 +++++++
> >> 2 files changed, 16 insertions(+)
> >>
> >>diff --git a/doc/filters.texi b/doc/filters.texi
> >>index 55a8ebae56..cfc10c8479 100644
> >>--- a/doc/filters.texi
> >>+++ b/doc/filters.texi
> >>@@ -10800,6 +10800,15 @@ timestamp of the first frame of the freeze. The
> >> @code{lavfi.freezedetect.freeze_end} metadata keys are set on the first frame
> >> after the freeze.
> >>
> >>+The @code{lavfi.freezedetect.mafd} metadata key is set for all frames except the
> >>+first reference frame. You can use it to drop frozen frames by metadata select
> >>+mode. Note that in this way the first few frozen frames(the detection interval)
> >>+are dropped also. An example is as follows:
> >>+@example
> >>+freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.001:function=greater
> >>+@end example
> 
> No, this is not what this is. This way you drop in the detection
> interval even if no freeze is detected. So this approach is only
> slightly different to selecting a very small (less than a frame)
> detection interval.

If one frame is detected as frozen frame, it'll be dropped. The freezedetect.mafd will be
the mafd between the next frame with the first frozen frame, if it's frozen frame(<threeshold),
still, it'll be continued drop. So we may think it's not frozen frame if only one frame mafd
less than the threshold, so you need set the threshold very small to avoid misdetecting.
With detection interval, you can't avoid misdetect still if the threshold isn't good choose.


> 
> So I don't see the point of this patch.
> 
> Regards,
> Marton
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> 
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
diff mbox

Patch

diff --git a/doc/filters.texi b/doc/filters.texi
index 55a8ebae56..cfc10c8479 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -10800,6 +10800,15 @@  timestamp of the first frame of the freeze. The
 @code{lavfi.freezedetect.freeze_end} metadata keys are set on the first frame
 after the freeze.
 
+The @code{lavfi.freezedetect.mafd} metadata key is set for all frames except the
+first reference frame. You can use it to drop frozen frames by metadata select
+mode. Note that in this way the first few frozen frames(the detection interval)
+are dropped also. An example is as follows:
+@example
+freezedetect,metadata=mode=select:key=lavfi.freezedetect.mafd:value=0.001:function=greater
+@end example
+
+
 The filter accepts the following options:
 
 @table @option
diff --git a/libavfilter/vf_freezedetect.c b/libavfilter/vf_freezedetect.c
index cc086afee6..3931bcfa2e 100644
--- a/libavfilter/vf_freezedetect.c
+++ b/libavfilter/vf_freezedetect.c
@@ -124,11 +124,14 @@  static av_cold void uninit(AVFilterContext *ctx)
     av_frame_free(&s->reference_frame);
 }
 
+static int set_meta(FreezeDetectContext *s, AVFrame *frame, const char *key, const char *value);
 static int is_frozen(FreezeDetectContext *s, AVFrame *reference, AVFrame *frame)
 {
     uint64_t sad = 0;
     uint64_t count = 0;
     double mafd;
+    char buf[64];
+
     for (int plane = 0; plane < 4; plane++) {
         if (s->width[plane]) {
             uint64_t plane_sad;
@@ -141,6 +144,10 @@  static int is_frozen(FreezeDetectContext *s, AVFrame *reference, AVFrame *frame)
     }
     emms_c();
     mafd = (double)sad / count / (1ULL << s->bitdepth);
+
+    snprintf(buf, sizeof(buf), "%0.5f", mafd);
+    set_meta(s, frame, "lavfi.freezedetect.mafd", buf);
+
     return (mafd <= s->noise);
 }