[FFmpeg-trac] #4354(undetermined:new): Big file size difference after using -c:v copy and -c:a copy

FFmpeg trac at avcodec.org
Thu Mar 5 16:27:21 CET 2015


#4354: Big file size difference after using -c:v copy and -c:a copy
--------------------------------------+----------------------------------
             Reporter:  Atarikid      |                     Type:  defect
               Status:  new           |                 Priority:  normal
            Component:  undetermined  |                  Version:  2.5.2
             Keywords:                |               Blocked By:
             Blocking:                |  Reproduced by developer:  0
Analyzed by developer:  0             |
--------------------------------------+----------------------------------
 I noticed some very strange when copying streams.

 You can reproduce this with any .m2t or .ts source file.
 Just copy the streams with -c:v copy -c:a copy

 Note the below example source file has 1 video stream and 1 audio stream.
 Do notice the BITRATE has changed from 27253 kb/s to 19490 kb/s
 How can this be the case when you copy the streams?

 Here is command line and output. Below you can find the ffmpeg info of
 both source and created file (about %25 smaller in file size)


 /Users/atarikid/Library/Application\ Support/iFFmpeg5/FFmpeg  -i
 /Volumes/Data/movies/snl\ alabama\ shakes.m2t -c:a copy -c:v copy -f
 mpegts -y /Users/atarikid/Movies/snl\ alabama\ shakes.ts

 ffmpeg version 2.5.2 Copyright (c) 2000-2014 the FFmpeg developers
   built on Jan  1 2015 20:24:48 with llvm-gcc 4.2.1 (LLVM build
 2336.11.00)
   configuration: --prefix=/Volumes/tempdisk/sw --as=yasm --enable-gpl
 --enable-pthreads --disable-ffplay --disable-ffserver --disable-shared
 --enable-static --enable-libvpx --disable-decoder=libvpx --enable-
 libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis
 --enable-libx264 --enable-libx265 --enable-libxvid --enable-zlib --enable-
 avfilter --enable-fontconfig --enable-libfreetype --enable-libass
 --enable-libutvideo --enable-filters --enable-postproc --enable-runtime-
 cpudetect
   libavutil      54. 15.100 / 54. 15.100
   libavcodec     56. 13.100 / 56. 13.100
   libavformat    56. 15.102 / 56. 15.102
   libavdevice    56.  3.100 / 56.  3.100
   libavfilter     5.  2.103 /  5.  2.103
   libswscale      3.  1.101 /  3.  1.101
   libswresample   1.  1.100 /  1.  1.100
   libpostproc    53.  3.100 / 53.  3.100
 [mpeg2video @ 0x7faf3b824200] Invalid frame dimensions 0x0.
     Last message repeated 1 times
     Last message repeated 2 times
     Last message repeated 3 times
     Last message repeated 4 times
     Last message repeated 5 times
     Last message repeated 6 times
     Last message repeated 7 times
     Last message repeated 8 times
     Last message repeated 9 times
     Last message repeated 10 times
     Last message repeated 11 times
     Last message repeated 12 times
     Last message repeated 13 times
     Last message repeated 14 times
     Last message repeated 14 times
 [mpegts @ 0x7faf3b81bc00] PES packet size mismatch
 Input #0, mpegts, from '/Volumes/Data/movies/snl alabama shakes.m2t':
   Duration: 00:04:52.51, start: 62014.858256, bitrate: 27253 kb/s
   Program 1
     Stream #0:0[0xec9]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002),
 yuv420p(tv), 1920x1080 [SAR 1:1 DAR 16:9], max. 25000 kb/s, 29.97 fps,
 29.97 tbr, 90k tbn, 59.94 tbc
     Stream #0:1[0xeca]: Audio: ac3 ([129][0][0][0] / 0x0081), 48000 Hz,
 5.1(side), fltp, 384 kb/s
 Output #0, mpegts, to '/Users/atarikid/Movies/snl alabama shakes.ts':
   Metadata:
     encoder         : Lavf56.15.102
     Stream #0:0: Video: mpeg2video ([2][0][0][0] / 0x0002), yuv420p,
 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, max. 25000 kb/s, 29.97 fps, 90k tbn,
 29.97 tbc
     Stream #0:1: Audio: ac3 ([129][0][0][0] / 0x0081), 48000 Hz,
 5.1(side), 384 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (copy)
   Stream #0:1 -> #0:1 (copy)
 Press [q] to stop, [?] for help
 frame= 2243 fps=0.0 q=-1.0 size=  170284kB time=00:01:15.78
 bitrate=18406.0kbits/s
 frame= 4274 fps=4273 q=-1.0 size=  337113kB time=00:02:23.55
 bitrate=19237.2kbits/s
 frame= 5618 fps=3745 q=-1.0 size=  447000kB time=00:03:08.40
 bitrate=19436.3kbits/s
 frame= 7700 fps=3849 q=-1.0 size=  617824kB time=00:04:17.87
 bitrate=19626.9kbits/s
 [mpegts @ 0x7faf3b81bc00] PES packet size mismatch
 frame= 8737 fps=3910 q=-1.0 Lsize=  695950kB time=00:04:52.47
 bitrate=19493.2kbits/s
 video:629879kB audio:13695kB subtitle:0kB other streams:0kB global
 headers:0kB muxing overhead: 8.138343%






 Original:
 Filesize = 996.468.808bytes (996,5MB)

 Last login: Thu Mar  5 15:42:41 on console
 atarikids-MacBook-Pro:~ atarikid$ /Users/atarikid/Desktop/ffmpeg -i
 /Volumes/Data/movies/snl\ alabama\ shakes.m2t
 ffmpeg version 2.5.2 Copyright (c) 2000-2014 the FFmpeg developers
   built on Jan  1 2015 20:24:48 with llvm-gcc 4.2.1 (LLVM build
 2336.11.00)
   configuration: --prefix=/Volumes/tempdisk/sw --as=yasm --enable-gpl
 --enable-pthreads --disable-ffplay --disable-ffserver --disable-shared
 --enable-static --enable-libvpx --disable-decoder=libvpx --enable-
 libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis
 --enable-libx264 --enable-libx265 --enable-libxvid --enable-zlib --enable-
 avfilter --enable-fontconfig --enable-libfreetype --enable-libass
 --enable-libutvideo --enable-filters --enable-postproc --enable-runtime-
 cpudetect
   libavutil      54. 15.100 / 54. 15.100
   libavcodec     56. 13.100 / 56. 13.100
   libavformat    56. 15.102 / 56. 15.102
   libavdevice    56.  3.100 / 56.  3.100
   libavfilter     5.  2.103 /  5.  2.103
   libswscale      3.  1.101 /  3.  1.101
   libswresample   1.  1.100 /  1.  1.100
   libpostproc    53.  3.100 / 53.  3.100
 Input #0, mpegts, from '/Volumes/Data/movies/snl alabama shakes.m2t':
   Duration: 00:04:52.51, start: 62014.858256, bitrate: 27253 kb/s
   Program 1
     Stream #0:0[0xec9]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002),
 yuv420p(tv), 1920x1080 [SAR 1:1 DAR 16:9], max. 25000 kb/s, 29.97 fps,
 29.97 tbr, 90k tbn, 59.94 tbc
     Stream #0:1[0xeca]: Audio: ac3 ([129][0][0][0] / 0x0081), 48000 Hz,
 5.1(side), fltp, 384 kb/s
 At least one output file must be specified
 atarikids-MacBook-Pro:~ atarikid$






 Passthru version:
 Filesize = 712.652.728bytes (712,7MB)

 atarikids-MacBook-Pro:~ atarikid$ /Users/atarikid/Desktop/ffmpeg -i
 /Users/atarikid/Desktop/snl\ alabama\ shakes.ts
 ffmpeg version 2.5.2 Copyright (c) 2000-2014 the FFmpeg developers
   built on Jan  1 2015 20:24:48 with llvm-gcc 4.2.1 (LLVM build
 2336.11.00)
   configuration: --prefix=/Volumes/tempdisk/sw --as=yasm --enable-gpl
 --enable-pthreads --disable-ffplay --disable-ffserver --disable-shared
 --enable-static --enable-libvpx --disable-decoder=libvpx --enable-
 libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis
 --enable-libx264 --enable-libx265 --enable-libxvid --enable-zlib --enable-
 avfilter --enable-fontconfig --enable-libfreetype --enable-libass
 --enable-libutvideo --enable-filters --enable-postproc --enable-runtime-
 cpudetect
   libavutil      54. 15.100 / 54. 15.100
   libavcodec     56. 13.100 / 56. 13.100
   libavformat    56. 15.102 / 56. 15.102
   libavdevice    56.  3.100 / 56.  3.100
   libavfilter     5.  2.103 /  5.  2.103
   libswscale      3.  1.101 /  3.  1.101
   libswresample   1.  1.100 /  1.  1.100
   libpostproc    53.  3.100 / 53.  3.100
 Input #0, mpegts, from '/Users/atarikid/Desktop/snl alabama shakes.ts':
   Duration: 00:04:52.51, start: 1.400000, bitrate: 19490 kb/s
   Program 1
     Metadata:
       service_name    : Service01
       service_provider: FFmpeg
     Stream #0:0[0x100]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002),
 yuv420p(tv), 1920x1080 [SAR 1:1 DAR 16:9], max. 25000 kb/s, 29.97 fps,
 29.97 tbr, 90k tbn, 59.94 tbc
     Stream #0:1[0x101]: Audio: ac3 ([129][0][0][0] / 0x0081), 48000 Hz,
 5.1(side), fltp, 384 kb/s
 At least one output file must be specified

--
Ticket URL: <https://trac.ffmpeg.org/ticket/4354>
FFmpeg <https://ffmpeg.org>
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