[FFmpeg-user] Does "cat" degrade video quality?

MyCraigs List mycraigsl at ymail.com
Fri Dec 2 14:36:44 EET 2022

I'm running Debian 11.
I use the command line "cat" to concatenate videos of all the same quality together.  All VOB files are cat'd together and none others.  The second bunch of videos I cat together are from a Sony video camera and are "MTS" files.  That's to say I do not cat VOB and MTS files together.
The command I use for VOB is (at command line) $ cat File_1.VOB  File_2.VOB> New_File_1.VOBThe command I use for MTS is (at command line) $ cat File_1.MTS File_2.MTS> New_File_2.MTS

Not wanting to lose any video or audio quality, does "cat" files degrade their quality?  If it does can you recommend a code line that'll preserve the quality?

VOB file example;
Input #0, mpeg, from 'VTS_06_1.VOB':
  Duration: 00:00:32.53, start: 0.213367, bitrate: 6688 kb/s
    Stream #0:0[0x1bf]: Data: dvd_nav_packet
    Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, bottom first), 720x480 [SAR 8:9 DAR 4:3], 5000 kb/s, 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
    Side data:
      cpb: bitrate max/min/avg: 5000000/0/0 buffer size: 1835008 vbv_delay: N/A
    Stream #0:2[0xa0]: Audio: pcm_dvd, 48000 Hz, stereo, s16, 1536 kb/s

MTS file example;
Input #0, mpegts, from '00105.MTS':
  Duration: 00:00:49.06, start: 1.033367, bitrate: 22411 kb/s
  Program 1 
    Stream #0:0[0x1011]: Video: h264 (High) (HDMV / 0x564D4448), yuv420p(top first), 1920x1080 [SAR 1:1 DAR 16:9], 29.97 fps, 59.94 tbr, 90k tbn, 59.94 tbc
    Stream #0:1[0x1100]: Audio: ac3 (AC-3 / 0x332D4341), 48000 Hz, stereo, fltp, 256 kb/s
    Stream #0:2[0x1200]: Subtitle: hdmv_pgs_subtitle ([144][0][0][0] / 0x0090), 1920x1080

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