[FFmpeg-user] 50 Mbps Ifram mpg2 with scaling and pad --sync problem

[Jim Shupert]

On 8/2/2013 12:46 PM, Jim Shupert, Jr wrote:
> Friends,
> I wish to take 720x486 Unc 8 bit rawVideo with 2 chn  pcm audio
> and make 50 mbps Iframe mpg2 422 1920x1080i with mpg2 audio
>
> I realize that upScaling is not best - but I do need to in this situation.
>
> I have something that I think is close but the audio goes out of sync.
> I wonder why?
>
> You will see I have my buffer set rather high - i did that to avoid
> ...
> [mpeg @ 0x307afa0] buffer underflow i=0 bufi=354801 size=358510
> [mpeg @ 0x307afa0] packet too large, ignoring buffer limits to mux it
> [mpeg @ 0x307afa0] buffer underflow i=0 bufi=354801 size=358510
> ...
>
> here is my command
>
> jj at gagarin:~$ ffmpeg -i /media/data/z_parts/dog.avi -vf
> "scale=1620:1080,pad=1920:1080:150:0:black"  -pix_fmt yuv422p -c:v
> mpeg2video  -minrate 50000k -maxrate 50000k -b:v 50000k -intra -flags
> +ildct+low_delay -g 1  -dc 10  -ps 1 -qmin 1 -qmax 3 -top 1  -bufsize
> 5000000 -rc_init_occupancy 2000000 -rc_buf_aggressivity 0.25  -c:a mp2
> -async 1 -b:a 224k -ar 48000 -ac 2    /media/data/jtest/dog-3a_1080i.mpg
>
> jj at gagarin:~$ ffmpeg -i /media/data/z_parts/dog.avi -vf
> "scale=1620:1080,pad=1920:1080:150:0:black"  -pix_fmt yuv422p -c:v
> mpeg2video  -minrate 50000k -maxrate 50000k -b:v 50000k -intra -flags
> +ildct+low_delay -g 1  -dc 10  -ps 1 -qmin 1 -qmax 3 -top 1  -bufsize
> 5000000 -rc_init_occupancy 2000000 -rc_buf_aggressivity 0.25  -c:a mp2
> -async 1 -b:a 224k -ar 48000 -ac 2    /media/data/jtest/dog-3a_1080i.mpg
> ffmpeg version git-2012-09-24-fd63c2f Copyright (c) 2000-2012 the FFmpeg
> developers
>    built on Sep 24 2012 14:09:13 with gcc 4.4.3 (Ubuntu 4.4.3-4ubuntu5.1)
>    configuration: --enable-gpl --enable-libfaac --enable-libmp3lame
> --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora
> --enable-libvorbis --enable-libvpx --enable-libx264 --enable-nonfree
> --enable-version3 --enable-x11grab
>    libavutil      51. 73.101 / 51. 73.101
>    libavcodec     54. 58.100 / 54. 58.100
>    libavformat    54. 28.101 / 54. 28.101
>    libavdevice    54.  2.101 / 54.  2.101
>    libavfilter     3. 17.100 /  3. 17.100
>    libswscale      2.  1.101 /  2.  1.101
>    libswresample   0. 15.100 /  0. 15.100
>    libpostproc    52.  0.100 / 52.  0.100
> [avi @ 0x28b5240] non-interleaved AVI
> Guessed Channel Layout for  Input Stream #0.1 : stereo
> Input #0, avi, from '/media/data/z_parts/dog.avi':
>    Duration: 00:00:05.03, start: 0.000000, bitrate: 170941 kb/s
>      Stream #0:0: Video: rawvideo (UYVY / 0x59565955), uyvy422, 720x486,
> 29.97 tbr, 29.97 tbn, 29.97 tbc
>      Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000 Hz,
> stereo, s16, 1536 kb/s
> File '/media/data/jtest/dog-3a_1080i.mpg' already exists. Overwrite ? [y/N] y
> -async is forwarded to lavfi similarly to -af
> aresample=min_comp=0.001:min_hard_comp=0.100000.
> Output #0, mpeg, to '/media/data/jtest/dog-3a_1080i.mpg':
>    Metadata:
>      encoder         : Lavf54.28.101
>      Stream #0:0: Video: mpeg2video, yuv422p, 1920x1080, q=1-3, 50000 kb/s,
> 90k tbn, 29.97 tbc
>      Stream #0:1: Audio: mp2, 48000 Hz, stereo, s16, 224 kb/s
> Stream mapping:
>    Stream #0:0 -> #0:0 (rawvideo -> mpeg2video)
>    Stream #0:1 -> #0:1 (pcm_s16le -> mp2)
> Press [q] to stop, [?] for help
> [mpeg2video @ 0x28b6800] rc buffer underflow
>      Last message repeated 24 times
> frame=   25 fps=0.0 q=24.8 size=    6190kB time=00:00:00.83
> bitrate=60789.4kbitsrc buffer underflow
> [mpeg2video @ 0x28b6800] rc buffer underflow
>
Maybe I could ask another way..
what might be the suggested means to scale raw video , uncompressed d1 
720x486 ntsc w pcm audio to 50 Mbps I fram mpg2.
I am scaling and padding . My audio comes out of sync.
Likely this is unrelated to the scaling and padding - but maybe not.
and
Does anyone have an opinion on buffer setting?

Thank you

best regards