[FFmpeg-user] MTS to MP4 lossless conversion issues

[Nick Gilmour]

Hi all,

my camera creates video files in AVCHD format. I want to  convert them to
lossless MP4 format. I have googled and found this command:

*ffmpeg -i in.MTS -vcodec copy -acodec copy -sn out.mp4*

with this command an mp4 file is indeed generated but I see this in the
console output (file attached):


*track 1: codec frame size is not set*

1. I googled also about this but I still don't know what does that mean and
how I should deal with it. Is it an error or should I change something?

2. I also see with VLC > Tools > Codec Information that the output file has
25 frames per sec, whereas the input file has 50 frames per sec. This
although the output of the previous command shows 50 fps for the output
file. So what is going on? Is VLC wrong? How can I get the 50 fps in the
output file? Do 25 fps less mean reduced quality?

3. The AVCHD format comes also with other files except MTS e.g. CPI. Are
these important for the conversion or for use with video editing tools
like Kdenlive?

Regards
Nick
-------------- next part --------------
$ ffmpeg -i 00000.MTS -vcodec copy -acodec copy -sn 00000.ffmpeg1.mp4
ffmpeg version 3.3.2-1~16.04.york1 Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.4) 20160609
  configuration: --prefix=/usr --extra-version='1~16.04.york1' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
  libavutil      55. 58.100 / 55. 58.100
  libavcodec     57. 89.100 / 57. 89.100
  libavformat    57. 71.100 / 57. 71.100
  libavdevice    57.  6.100 / 57.  6.100
  libavfilter     6. 82.100 /  6. 82.100
  libavresample   3.  5.  0 /  3.  5.  0
  libswscale      4.  6.100 /  4.  6.100
  libswresample   2.  7.100 /  2.  7.100
  libpostproc    54.  5.100 / 54.  5.100
Input #0, mpegts, from '00000.MTS':
  Duration: 00:00:15.10, start: 0.888889, bitrate: 13700 kb/s
  Program 1 
    Stream #0:0[0x1011]: Video: h264 (High) (HDMV / 0x564D4448), yuv420p(tv, progressive), 1280x720 [SAR 1:1 DAR 16:9], 50 fps, 25 tbr, 90k tbn, 100 tbc
    Stream #0:1[0x1100]: Audio: ac3 (AC-3 / 0x332D4341), 48000 Hz, stereo, fltp, 192 kb/s
    Stream #0:2[0x1200]: Subtitle: hdmv_pgs_subtitle ([144][0][0][0] / 0x0090), 1280x720
[mp4 @ 0x55a37b91a4a0] track 1: codec frame size is not set
Output #0, mp4, to '00000.ffmpeg1.mp4':
  Metadata:
    encoder         : Lavf57.71.100
    Stream #0:0: Video: h264 (High) ([33][0][0][0] / 0x0021), yuv420p(tv, progressive), 1280x720 [SAR 1:1 DAR 16:9], q=2-31, 50 fps, 25 tbr, 90k tbn, 90k tbc
    Stream #0:1: Audio: ac3 ([165][0][0][0] / 0x00A5), 48000 Hz, stereo, fltp, 192 kb/s
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame=  377 fps=0.0 q=-1.0 Lsize=   23852kB time=00:00:15.07 bitrate=12964.2kbits/s speed= 247x    
video:23490kB audio:354kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.033670%