[FFmpeg-user] ffmpeg with x264 codec - Aspect ratio doesn't follow input

chronek chronek at interia.eu
Wed May 25 15:33:00 CEST 2016


I doubt that it reach any release, but you can build own ffmpeg with 
their patch proposed

W dniu 2016-05-25 o 15:04, Richard F pisze:
> Yes - that's the exact issue - multiple aspect ratio changes, and I'm
> not sure how to find where they occur without a lot of complexity
> About 7 years ago Jarmo Torvinen proposed something to address this
> exact issue - did this ever reach the build, if so how to activate ?
> http://x264-devel.videolan.narkive.com/TlgcMaKZ/reconfiguring-x264-aspect-ratio-in-the-middle-of-stream
>
>
> On 25/05/2016 13:53, chronek wrote:
>> Didnt read to end before, are you have 2 aspect ratio in stream? Then
>> you need split and process each part alone...
>>
>> W dniu 2016-05-25 o 11:18, Richard F pisze:
>>> Thanks for your reply,
>>>
>>> The stream info for this file is as follows. As you can see the DAR
>>> starts as 16:9, but the aspect changes several times during the
>>> recording, x264 doesn't follow the changes, stays at 16:9.
>>>
>>> If I force the SAR as you suggest the output is narrower than 4:3 and
>>> still doesn't change with incoming aspect changes.
>>>
>>> Input #0, mpegts, from '00001.ts':
>>>     Duration: 00:59:49.47, start: 4529.649200, bitrate: 1477 kb/s
>>>     Program 132
>>>       Stream #0:0[0x18a1]: Video: mpeg2video (Main) ([2][0][0][0] /
>>> 0x0002), yuv420p(tv), 544x576 [SAR 32:17 DAR 16:9], max. 15000 kb/s, 25
>>> fps, 25 tbr, 90k tbn, 50 tbc
>>>       Stream #0:1[0x18a2](eng): Audio: mp2 ([3][0][0][0] / 0x0003), 48000
>>> Hz, stereo, s16p, 128 kb/s
>>>       Stream #0:2[0x18a3](eng): Audio: mp3 ([3][0][0][0] / 0x0003), 0
>>> channels, s16p
>>>       Stream #0:3[0x18a6](eng): Subtitle: dvb_subtitle ([6][0][0][0] /
>>> 0x0006)
>>>
>>> If I analyse the stream 5 minutes into the programme, like so:
>>> ffmpeg -loglevel quiet -ss 00:05:00 -i "00001.ts" -t 10 -c copy
>>> -avoid_negative_ts 1 -f nut pipe:1 | ffmpeg -hide_banner -i pipe:0
>>>
>>> Then the video stream is as follows:
>>>
>>> Stream #0:0: Video: mpeg2video (Main) (mpg2 / 0x3267706D), yuv420p(tv),
>>> 544x576 [SAR 24:17 DAR 4:3], max. 15000 kb/s, SAR 32:17 DAR 16:9, 25
>>> fps, 25 tbr, 90k tbn, 50 tbc
>>>
>>> So it is meant to show as 4:3 here.
>>> I'm assuming the 2 sets of SAR/DAR are for container and stream which is
>>> why it still shows as 16:9 after ffmpeg processing ?
>>>
>>>
>>>
>>> On 25/05/2016 08:10, chronek wrote:
>>>> Maybe your source not have sar 1:1... setdar will not change
>>>> resolution, it will change only information about aspectratio and some
>>>> players not read desired aspect ratio... Best try change to resolution
>>>> what yuou want and setsar for it... ( -vf scale=x:y,setsar=1 )
>>>>
>>>> W dniu 2016-05-25 o 09:00, Richard F pisze:
>>>>> Hi list,
>>>>>
>>>>> I have a number of MPEG2 TS DVB recordings that have aspect ratio
>>>>> changes - e.g. older films or 4:3 programmes that have 16:9
>>>>> continuity, trailers, adverts etc.
>>>>>
>>>>> I want to transcode to H264 using ffmpeg (3.02), but the output
>>>>> aspect ratio does not follow the source when using the H264 codec.
>>>>> But the aspect ratio does follow when using the xvid/mp4 codec.
>>>>> I need x264 not mp4.
>>>>> The problem is that (I think) the container DAR or SAR stays at 16:9
>>>>> all the way through but the stream SAR or DAR doesn't follow the
>>>>> source for whatever reason
>>>>>
>>>>> Is there a way to make x264 output follow the source aspect ratio at
>>>>> the stream level ?
>>>>>
>>>>> Failing example :
>>>>> ffmpeg -y -i 00001.ts -map 0:0 -map 0:1 -map 0:3 -c:v libx264 -preset
>>>>> veryfast -profile:v high -level 4.0 -crf 20 -flags +loop -flags +ilme
>>>>> -vf yadif=0:-1:0 -c:a:0 aac -b:a:0 128k -c:s copy -f mpegts file-1.ts
>>>>> (same if I take out the profile and deinterlace settings)
>>>>>
>>>>> Working example (but large file and not so good quality, even if I
>>>>> could use it):
>>>>> ffmpeg -y -i 00001.ts -map 0:0 -map 0:1 -map 0:3 -c:v libxvid -q:v 3
>>>>> -c:a:0 aac -b:a:0 128k -c:s copy -f mpegts file-1.ts
>>>>>
>>>>> If I add -vf setdar=dar=4/3, I can force the x264 version to be 4/3
>>>>> but then all parts of the recording are always 4/3 which is also
>>>>> wrong.
>>>>>
>>>>> Behaviour is the same on VLC player, ffplay, and Kodi.
>>>>>
>>>>> Appreciate any pointers
>>>>> Thanks
>>>>> Richard
>>>>>
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> ffmpeg-user mailing list
>>>>> ffmpeg-user at ffmpeg.org
>>>>> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>>>>>
>>>>> To unsubscribe, visit link above, or email
>>>>> ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".
>>>> _______________________________________________
>>>> ffmpeg-user mailing list
>>>> ffmpeg-user at ffmpeg.org
>>>> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>>>>
>>>> To unsubscribe, visit link above, or email
>>>> ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".
>>> _______________________________________________
>>> ffmpeg-user mailing list
>>> ffmpeg-user at ffmpeg.org
>>> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>>>
>>> To unsubscribe, visit link above, or email
>>> ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".
>> _______________________________________________
>> ffmpeg-user mailing list
>> ffmpeg-user at ffmpeg.org
>> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>>
>> To unsubscribe, visit link above, or email
>> ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".
>
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> ffmpeg-user-request at ffmpeg.org with subject "unsubscribe".



More information about the ffmpeg-user mailing list