[FFmpeg-devel] [PATCH] change frame_aspect_ratio to AVRational

[Baptiste Coudurier]

On 6/11/2009 4:27 AM, Michael Niedermayer wrote:
> On Wed, Jun 10, 2009 at 09:23:40PM -0700, Baptiste Coudurier wrote:
>> Hi
>>
>> $subject, mainly to avoid using double which behaves not correctly
>> when using 16:9 commandline.
> [...]
>> @@ -3012,7 +3012,8 @@
>>          st->stream_copy = 1;
>>          video_enc->codec_type = CODEC_TYPE_VIDEO;
>>          video_enc->sample_aspect_ratio =
>> -        st->sample_aspect_ratio = av_d2q(frame_aspect_ratio*frame_height/frame_width, 255);
>> +        st->sample_aspect_ratio =
>> +            av_mul_q(frame_aspect_ratio, (AVRational){ frame_height, frame_width });
>>      } else {
>>          const char *p;
>>          int i;
>> @@ -3039,7 +3040,8 @@
>>  
>>          video_enc->width = frame_width + frame_padright + frame_padleft;
>>          video_enc->height = frame_height + frame_padtop + frame_padbottom;
>> -        video_enc->sample_aspect_ratio = av_d2q(frame_aspect_ratio*video_enc->height/video_enc->width, 255);
>> +        video_enc->sample_aspect_ratio =
>> +            av_mul_q(frame_aspect_ratio, (AVRational){ frame_height, frame_width });
>>          video_enc->pix_fmt = frame_pix_fmt;
>>          st->sample_aspect_ratio = video_enc->sample_aspect_ratio;
>>  
> 
> previously these where limited to 255/255 now they arent anymore, i think
> some codecs dont support arbitrary fractions

Ok, quick survey:
theora encoder supports rational.
h264 supports rational on 16bits.
libxvid indeed checks for 255/255.
mpeg12 converts back to float and match supported ones.
mjpeg is rational on 16bits.
h263/mpeg4 sar is rational on 8bits.

Ok to add av_reduce to codecs needing it ?

-- 
Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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