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UPDATE 2

I guess if I use -codec copy then I will be unable to cut at precise moment. Moment precision is a priority. So I agree with quality loss but it should not be so drastical.

UPDATE 2

I guess if I use -codec copy then I will be unable to cut at precise moment. Moment precision is a priority. So I agree with quality loss but it should not be so drastical.

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UPDATE

Even if re-encoding, then why so drastical change? Can we re-encode so that it will be nearly invisible degrading of quality?

UPDATE

Even if re-encoding, then why so drastical change? Can we re-encode so that it will be nearly invisible degrading of quality?

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Why does quality degrade so much if just cutting video with ffmpeg?

I have tried to cut video with the following command

ffmpeg -i "Вспомнить все (Total Recall, 1990).avi"  -ss 01:07:29 -to 01:08:05 fight.avi

Output:

Input #0, avi, from '╨Т╤Б╨┐╨╛╨╝╨╜╨╕╤В╤М ╨▓╤Б╨╡ (Total Recall, 1990).avi':
  Metadata:
    encoder         : VirtualDubMod 1.5.10.2 (build 2540/release)
    artist          : Menen
  Duration: 01:53:33.69, start: 0.000000, bitrate: 3660 kb/s
    Stream #0:0: Video: mpeg4 (Advanced Simple Profile) (XVID / 0x44495658), yuv420p, 704x384 [SAR 1:1 DAR 11:6], 2295 kb/s, 23.98 fps, 23.98 tbr, 23.
98 tbn, 23.98 tbc
    Stream #0:1: Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, 5.1(side), fltp, 448 kb/s
    Stream #0:2: Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, 5.1(side), fltp, 448 kb/s
    Stream #0:3: Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, 5.1(side), fltp, 448 kb/s
File 'fight.avi' already exists. Overwrite ? [y/N] y
Output #0, avi, to 'fight.avi':
  Metadata:
    IART            : Menen
    ISFT            : Lavf55.43.100
    Stream #0:0: Video: mpeg4 (FMP4 / 0x34504D46), yuv420p, 704x384 [SAR 1:1 DAR 11:6], q=2-31, 200 kb/s, 23.98 fps, 23.98 tbn, 23.98 tbc
    Metadata:
      encoder         : Lavc55.67.100 mpeg4
    Stream #0:1: Audio: mp3 (libmp3lame) (U[0][0][0] / 0x0055), 48000 Hz, stereo, fltp
    Metadata:
      encoder         : Lavc55.67.100 libmp3lame
Stream mapping:
  Stream #0:0 -> #0:0 (mpeg4 (native) -> mpeg4 (native))
  Stream #0:1 -> #0:1 (ac3 (native) -> mp3 (libmp3lame))
Press [q] to stop, [?] for help
frame=  863 fps= 20 q=31.0 Lsize=    2690kB time=00:00:36.00 bitrate= 612.1kbits/s
video:2061kB audio:563kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 2.500957%

The resulting video has obviously worse quality, with apparent big MPEG squares visible

Why?

How to avoid?