[FFmpeg-cvslog] r17572 - in trunk/libavcodec: mpeg12.c mpegvideo_parser.c

[Baptiste Coudurier]

On 2/24/2009 12:23 PM, cehoyos wrote:
> Author: cehoyos
> Date: Tue Feb 24 21:23:19 2009
> New Revision: 17572
> 
> Log:
> Correct time_base and repeat_pict for MPEG2 video.
> 
> Patch by Ivan Schreter, schreter gmx net
> 
> Modified:
>    trunk/libavcodec/mpeg12.c
>    trunk/libavcodec/mpegvideo_parser.c
> 
> Modified: trunk/libavcodec/mpeg12.c
> ==============================================================================
> --- trunk/libavcodec/mpeg12.c	Tue Feb 24 21:19:59 2009	(r17571)
> +++ trunk/libavcodec/mpeg12.c	Tue Feb 24 21:23:19 2009	(r17572)
> @@ -1275,7 +1275,7 @@ static int mpeg_decode_postinit(AVCodecC
>              av_reduce(
>                  &s->avctx->time_base.den,
>                  &s->avctx->time_base.num,
> -                ff_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num,
> +                ff_frame_rate_tab[s->frame_rate_index].num * s1->frame_rate_ext.num*2,
>                  ff_frame_rate_tab[s->frame_rate_index].den * s1->frame_rate_ext.den,
>                  1<<30);
>          //MPEG-2 aspect
> 
> Modified: trunk/libavcodec/mpegvideo_parser.c
> ==============================================================================
> --- trunk/libavcodec/mpegvideo_parser.c	Tue Feb 24 21:19:59 2009	(r17571)
> +++ trunk/libavcodec/mpegvideo_parser.c	Tue Feb 24 21:23:19 2009	(r17572)
> @@ -81,7 +81,7 @@ static void mpegvideo_extract_headers(AV
>                          pc->height |=( vert_size_ext << 12);
>                          avctx->bit_rate += (bit_rate_ext << 18) * 400;
>                          avcodec_set_dimensions(avctx, pc->width, pc->height);
> -                        avctx->time_base.den = pc->frame_rate.den * (frame_rate_ext_n + 1);
> +                        avctx->time_base.den = pc->frame_rate.den * (frame_rate_ext_n + 1) * 2;
>                          avctx->time_base.num = pc->frame_rate.num * (frame_rate_ext_d + 1);
>                          avctx->codec_id = CODEC_ID_MPEG2VIDEO;
>                          avctx->sub_id = 2; /* forces MPEG2 */

I'm pretty sure this commit broke codec frame rate parsing for MPEG-2 in
MXF.

Seems stream 0 codec frame rate differs from container frame rate: 50.00
(50/1) -> 25.00 (25/1)
Input #0, mxf, from 'test.mxf':
  Duration: 00:00:18.20, start: 0.000000, bitrate: 2086 kb/s
    Stream #0.0: Video: mpeg2video, yuv420p, 320x240 [PAR 1:1 DAR 4:3],
104857 kb/s, 25 tbr, 25 tbn, 50 tbc
    Stream #0.1: Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
At least one output file must be specified

Worked fine before. You can just create a .mxf with FFmpeg:
ffmpeg -i <file> -ar 48000 test.mxf

If I remove "* 2" everything is fine again.

-- 
Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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