[FFmpeg-devel] [PATCH v3 3/3] avcodec: estimate output bitrate for ffv1/huffyuv codecs

[Tobias Rapp]

On 11.03.2017 16:29, Michael Niedermayer wrote:
> On Tue, Mar 07, 2017 at 03:39:19PM +0100, Tobias Rapp wrote:
>> Allows to get a more realistic total bitrate (and estimated file size)
>> in avi_write_header. Previously a static default value of 200k was
>> assumed.
>>
>> Signed-off-by: Tobias Rapp <t.rapp at noa-archive.com>
>> ---
>>  libavcodec/ffv1enc.c                           | 3 +++
>>  libavcodec/huffyuvenc.c                        | 3 +++
>>  tests/ref/vsynth/vsynth1-ffv1                  | 2 +-
>>  tests/ref/vsynth/vsynth1-ffv1-v0               | 2 +-
>>  tests/ref/vsynth/vsynth1-ffv1-v3-bgr0          | 2 +-
>>  tests/ref/vsynth/vsynth1-ffv1-v3-rgb48         | 2 +-
>>  tests/ref/vsynth/vsynth1-ffv1-v3-yuv420p       | 2 +-
>>  tests/ref/vsynth/vsynth1-ffv1-v3-yuv422p10     | 2 +-
>>  tests/ref/vsynth/vsynth1-ffv1-v3-yuv444p16     | 2 +-
>>  tests/ref/vsynth/vsynth1-ffvhuff               | 2 +-
>>  tests/ref/vsynth/vsynth1-ffvhuff420p12         | 2 +-
>>  tests/ref/vsynth/vsynth1-ffvhuff422p10left     | 2 +-
>>  tests/ref/vsynth/vsynth1-ffvhuff444            | 2 +-
>>  tests/ref/vsynth/vsynth1-ffvhuff444p16         | 2 +-
>>  tests/ref/vsynth/vsynth1-huffyuv               | 2 +-
>>  tests/ref/vsynth/vsynth1-huffyuvbgr24          | 2 +-
>>  tests/ref/vsynth/vsynth1-huffyuvbgra           | 2 +-
>>  tests/ref/vsynth/vsynth2-ffv1                  | 2 +-
>>  tests/ref/vsynth/vsynth2-ffv1-v0               | 2 +-
>>  tests/ref/vsynth/vsynth2-ffv1-v3-bgr0          | 2 +-
>>  tests/ref/vsynth/vsynth2-ffv1-v3-rgb48         | 2 +-
>>  tests/ref/vsynth/vsynth2-ffv1-v3-yuv420p       | 2 +-
>>  tests/ref/vsynth/vsynth2-ffv1-v3-yuv422p10     | 2 +-
>>  tests/ref/vsynth/vsynth2-ffv1-v3-yuv444p16     | 2 +-
>>  tests/ref/vsynth/vsynth2-ffvhuff               | 2 +-
>>  tests/ref/vsynth/vsynth2-ffvhuff420p12         | 2 +-
>>  tests/ref/vsynth/vsynth2-ffvhuff422p10left     | 2 +-
>>  tests/ref/vsynth/vsynth2-ffvhuff444            | 2 +-
>>  tests/ref/vsynth/vsynth2-ffvhuff444p16         | 2 +-
>>  tests/ref/vsynth/vsynth2-huffyuv               | 2 +-
>>  tests/ref/vsynth/vsynth2-huffyuvbgr24          | 2 +-
>>  tests/ref/vsynth/vsynth2-huffyuvbgra           | 2 +-
>>  tests/ref/vsynth/vsynth3-ffv1                  | 2 +-
>>  tests/ref/vsynth/vsynth3-ffv1-v0               | 2 +-
>>  tests/ref/vsynth/vsynth3-ffv1-v3-bgr0          | 2 +-
>>  tests/ref/vsynth/vsynth3-ffv1-v3-rgb48         | 2 +-
>>  tests/ref/vsynth/vsynth3-ffv1-v3-yuv420p       | 2 +-
>>  tests/ref/vsynth/vsynth3-ffv1-v3-yuv422p10     | 2 +-
>>  tests/ref/vsynth/vsynth3-ffv1-v3-yuv444p16     | 2 +-
>>  tests/ref/vsynth/vsynth3-ffvhuff               | 2 +-
>>  tests/ref/vsynth/vsynth3-ffvhuff420p12         | 2 +-
>>  tests/ref/vsynth/vsynth3-ffvhuff422p10left     | 2 +-
>>  tests/ref/vsynth/vsynth3-ffvhuff444            | 2 +-
>>  tests/ref/vsynth/vsynth3-ffvhuff444p16         | 2 +-
>>  tests/ref/vsynth/vsynth3-huffyuv               | 2 +-
>>  tests/ref/vsynth/vsynth3-huffyuvbgr24          | 2 +-
>>  tests/ref/vsynth/vsynth3-huffyuvbgra           | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffv1              | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffv1-v0           | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffv1-v3-bgr0      | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffv1-v3-rgb48     | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffv1-v3-yuv420p   | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffv1-v3-yuv422p10 | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffv1-v3-yuv444p16 | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffvhuff           | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffvhuff420p12     | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffvhuff422p10left | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffvhuff444        | 2 +-
>>  tests/ref/vsynth/vsynth_lena-ffvhuff444p16     | 2 +-
>>  tests/ref/vsynth/vsynth_lena-huffyuv           | 2 +-
>>  tests/ref/vsynth/vsynth_lena-huffyuvbgr24      | 2 +-
>>  tests/ref/vsynth/vsynth_lena-huffyuvbgra       | 2 +-
>>  62 files changed, 66 insertions(+), 60 deletions(-)
>>
>> diff --git a/libavcodec/ffv1enc.c b/libavcodec/ffv1enc.c
>> index 35f54c6..b57e8ba 100644
>> --- a/libavcodec/ffv1enc.c
>> +++ b/libavcodec/ffv1enc.c
>> @@ -894,6 +894,9 @@ slices_ok:
>>              }
>>      }
>>
>> +    // estimate compressed bitrate assuming 40% output size
>> +    avctx->bit_rate = ff_guess_coded_bitrate(avctx) * 2 / 5;
>> +
>>      return 0;
>>  }
>>
>> diff --git a/libavcodec/huffyuvenc.c b/libavcodec/huffyuvenc.c
>> index 89639b7..ddbaf14 100644
>> --- a/libavcodec/huffyuvenc.c
>> +++ b/libavcodec/huffyuvenc.c
>> @@ -446,6 +446,9 @@ FF_ENABLE_DEPRECATION_WARNINGS
>>
>>      s->picture_number=0;
>>
>> +    // estimate compressed bitrate assuming 60% output size
>> +    avctx->bit_rate = ff_guess_coded_bitrate(avctx) * 3 / 5;
>
> i dont like this, the value is basically random, and not the bitrate

OK, then consider this patch as dropped.

IMHO the current static value of 200000 is even worse but I can do the 
estimation outside of avcodec and pass it to the encoder/muxer via the 
"b" option.

Regards,
Tobias