[FFmpeg-user] VBV buffer size not set - during stream copy

[Hans Carlson]

On Sat, 5 Nov 2016, Carl Eugen Hoyos wrote:

> 2016-11-05 1:23 GMT+01:00 Hans Carlson <forbyta at gmx.com>:
>
>>   VBV buffer size not set, using default size of 130KB
>>   If you want the mpeg file to be compliant to some specification
>>   Like DVD, VCD or others, make sure you set the correct buffer size
>
>> What do I need to do to avoid this message?
>
> Use -target dvd or -target vcd, depending on what you are trying to 
> create.

If I use -target ntsc-dvd BEFORE -codec copy, then it doesn't make any 
difference, I still get the VBV buffer size warning.

If I use -target ntsc-dvd AFTER -codec copy, then it doesn't copy, it 
reencodes. I don't want to reencode, I want to COPY.

   $ ffmpeg -i TEST.mpg -target ntsc-dvd -codec copy -f vob TEST-COPY-latest-target-before.mpg
ffmpeg version N-82228-gfb240a6 Copyright (c) 2000-2016 the FFmpeg developers
   built with gcc 4.5.1 (GCC) 20100924 (Red Hat 4.5.1-4)
   configuration: --enable-gpl --enable-version3 --enable-nonfree --disable-static --enable-shared --disable-debug --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-x11grab --disable-ffplay --disable-ffserver
   libavutil      55. 35.100 / 55. 35.100
   libavcodec     57. 66.101 / 57. 66.101
   libavformat    57. 57.100 / 57. 57.100
   libavdevice    57.  2.100 / 57.  2.100
   libavfilter     6. 66.100 /  6. 66.100
   libswscale      4.  3.100 /  4.  3.100
   libswresample   2.  4.100 /  2.  4.100
   libpostproc    54.  2.100 / 54.  2.100
Input #0, mpeg, from 'TEST.mpg':
   Duration: 00:00:09.88, start: 0.540000, bitrate: 49 kb/s
     Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, progressive), 320x240 [SAR 1:1 DAR 4:3], 25 fps, 25 tbr, 90k tbn, 50 tbc
[vob @ 0x8f8b2c0] VBV buffer size not set, using default size of 130KB
If you want the mpeg file to be compliant to some specification
Like DVD, VCD or others, make sure you set the correct buffer size
Output #0, vob, to 'TEST-COPY-latest-target-before.mpg':
   Metadata:
     encoder         : Lavf57.57.100
     Stream #0:0: Video: mpeg2video (Main), yuv420p(tv, progressive), 320x240 [SAR 1:1 DAR 4:3], q=2-31, 6000 kb/s, 25 fps, 25 tbr, 90k tbn, 29.97 tbc
Stream mapping:
   Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
[vob @ 0x8f8b2c0] Timestamps are unset in a packet for stream 0. This is deprecated and will stop working in the future. Fix your code to set the timestamps properly
frame=  250 fps=0.0 q=-1.0 Lsize=      60kB time=00:00:09.92 bitrate=  49.5kbits/s speed=2.04e+03x
video:58kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 4.049180%

   $ ffmpeg -i TEST.mpg -codec copy -target ntsc-dvd -f vob TEST-COPY-latest-target-after.mpg
ffmpeg version N-82228-gfb240a6 Copyright (c) 2000-2016 the FFmpeg developers
   built with gcc 4.5.1 (GCC) 20100924 (Red Hat 4.5.1-4)
   configuration: --enable-gpl --enable-version3 --enable-nonfree --disable-static --enable-shared --disable-debug --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-x11grab --disable-ffplay --disable-ffserver
   libavutil      55. 35.100 / 55. 35.100
   libavcodec     57. 66.101 / 57. 66.101
   libavformat    57. 57.100 / 57. 57.100
   libavdevice    57.  2.100 / 57.  2.100
   libavfilter     6. 66.100 /  6. 66.100
   libswscale      4.  3.100 /  4.  3.100
   libswresample   2.  4.100 /  2.  4.100
   libpostproc    54.  2.100 / 54.  2.100
Input #0, mpeg, from 'TEST.mpg':
   Duration: 00:00:09.88, start: 0.540000, bitrate: 49 kb/s
     Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, progressive), 320x240 [SAR 1:1 DAR 4:3], 25 fps, 25 tbr, 90k tbn, 50 tbc
Output #0, vob, to 'TEST-COPY-latest-target-after.mpg':
   Metadata:
     encoder         : Lavf57.57.100
     Stream #0:0: Video: mpeg2video (Main), yuv420p, 720x480 [SAR 8:9 DAR 4:3], q=2-31, 6000 kb/s, 29.97 fps, 90k tbn, 29.97 tbc
     Metadata:
       encoder         : Lavc57.66.101 mpeg2video
     Side data:
       cpb: bitrate max/min/avg: 9000000/0/6000000 buffer size: 1835008 vbv_delay: -1
Stream mapping:
   Stream #0:0 -> #0:0 (mpeg2video (native) -> mpeg2video (native))
Press [q] to stop, [?] for help
frame=  300 fps=141 q=2.0 Lsize=     172kB time=00:00:09.94 bitrate= 141.7kbits/s dup=50 drop=0 speed=4.66x
video:169kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.759272%