[FFmpeg-user] way to reencode corrupted video

[Richard Bartczak]

There are fatal errors in the stream.

I did check it with a script (Linux) :

---

frame=    8 fps=0.0 q=40.0 size=       0kB time=00:00:01.13 bitrate=  
0.0kbits/s dup=21 drop=0 speed=12.8x
frame=   26 fps=0.0 q=49.0 size=       0kB time=00:00:01.83 bitrate=  
0.0kbits/s dup=21 drop=0 speed=3.07x
frame=   69 fps= 62 q=49.0 size=       0kB time=00:00:03.56 bitrate=  
0.0kbits/s dup=21 drop=0 speed=3.18x
frame=  120 fps= 74 q=50.0 size=       0kB time=00:00:05.61 bitrate=  
0.0kbits/s dup=21 drop=0 speed=3.46x
frame=  167 fps= 79 q=49.0 size=       0kB time=00:00:07.48 bitrate=  
0.0kbits/s dup=21 drop=0 speed=3.52x
frame=  209 fps= 79 q=49.0 size=       0kB time=00:00:09.15 bitrate=  
0.0kbits/s dup=21 drop=0 speed=3.46x
frame=  260 fps= 83 q=48.0 size=     368kB time=00:00:11.20 bitrate=
269.2kbits/s dup=21 drop=0 speed=3.56x
frame=  309 fps= 84 q=49.0 size=     368kB time=00:00:13.16 bitrate=
229.1kbits/s dup=21 drop=0 speed=3.58x
frame=  354 fps= 85 q=49.0 size=     368kB time=00:00:14.95 bitrate=
201.6kbits/s dup=21 drop=0 speed=3.58x
[h264 @ 0x574eb5937540] cabac decode of qscale diff failed at 59 6
[h264 @ 0x574eb5937540] error while decoding MB 59 6, bytestream 77049
[h264 @ 0x574eb5937540] concealing 7430 DC, 7430 AC, 7430 MV errors in P
frame
[NULL @ 0x574eb57c9700] Invalid NAL unit size (60897492 > 110161).
[NULL @ 0x574eb57c9700] missing picture in access unit with size 110165
[h264 @ 0x574eb594b680] Invalid NAL unit size (60897492 > 110161).
[h264 @ 0x574eb594b680] Error splitting the input into NAL units.
[NULL @ 0x574eb57c9700] Invalid NAL unit size (-1600997495 > 84591).
[NULL @ 0x574eb57c9700] missing picture in access unit with size 84595
[NULL @ 0x574eb57c9700] Invalid NAL unit size (1695808648 > 76726).
[NULL @ 0x574eb57c9700] missing picture in access unit with size 76730
[h264 @ 0x574eb588c480] Invalid NAL unit size (-1600997495 > 84591).
[h264 @ 0x574eb588c480] Error splitting the input into NAL units.
[h264 @ 0x574eb58a0380] Invalid NAL unit size (1695808648 > 76726).
[h264 @ 0x574eb58a0380] Error splitting the input into NAL units.
[NULL @ 0x574eb57c9700] Invalid NAL unit size (540206825 > 109538).
[NULL @ 0x574eb57c9700] missing picture in access unit with size 109542
[h264 @ 0x574eb57e40c0] Invalid NAL unit size (540206825 > 109538).
[h264 @ 0x574eb57e40c0] Error splitting the input into NAL units.
[NULL @ 0x574eb57c9700] Invalid NAL unit size (1072494654 > 74994).
[NULL @ 0x574eb57c9700] missing picture in access unit with size 74998
[h264 @ 0x574eb5844d00] Invalid NAL unit size (1072494654 > 74994).
[h264 @ 0x574eb5844d00] Error splitting the input into NAL units.
[vist#0:0/h264 @ 0x574eb57cfe00] corrupt decoded frame
[vist#0:0/h264 @ 0x574eb57cfe00] Error submitting packet to decoder:
Invalid data found when processing input
     Last message repeated 4 times

frame=  392 fps= 84 q=49.0 size=     368kB time=00:00:16.51 bitrate=
182.6kbits/s dup=26 drop=0 speed=3.53x
frame=  436 fps= 84 q=49.0 size=     368kB time=00:00:18.28 bitrate=
164.9kbits/s dup=26 drop=0 speed=3.53x

---

It leads to the missing audio after this error.

This error must be removed to reencode :

ffmpeg -i "test.mp4" -codec copy -ss 00:00:00.000 -t 00:00:14.950
"test1.mp4"

ffmpeg -i "test.mp4" -codec copy -ss 00:00:16.510 -t 00:00:50.080
"test2.mp4"

But to "cat" the files via ffmpeg, all errors must be removed :

All mp4 files of the directory will be "cat"

ffmpeg -safe 0 -f concat -i <(printf "file '$PWD/%s'\n" *.mp4) -c copy
test.mp4

But with Avidemux you can ad all videos per drag + drop, after all, save
the files in copy mode to one-mp4 and reencode as you wish.

The script to get all errors with the respective timestamp :

#!/bin/bash

while IFS= read -r -d $'\0' video
do
     filename=$(basename -- "$video")
     filename="${filename%.*}"

     ffmpeg -y -i "$video" -vcodec libx264 -crf 51 -preset ultrafast
-acodec copy -f mp4 -movflags frag_keyframe+empty_moov+delay_moov pipe:1
 >/dev/null 2>"${filename}.txt" </dev/null
     TxtFileName="${filename}.txt"
     mystring=${TxtFileName}
     echo $mystring
     grep -i -n 'error\|duplicate\|failure\|missing\|POCs\|corrupt'
"${TxtFileName}"
     echo "Ready"

done < <(find -iregex ".*\.\(mp4\|mkv\|m2ts\|mpg\|ts\)" -print0)
#dos2unix -c mac "${TxtFileName}"
#grep -C 5 -i -n 'error\|duplicate\|failure' "${TxtFileName}"
echo "Ready"
read pause


All video files of the directory will be checked, the result you will
find in the txt-file.

Regards



Am 25.02.25 um 03:02 schrieb BloodMan:
> Hello,
>
> wetransfer mp4 test file: https://we.tl/t-BJKuiAHTKQ
>
> The video plays using VLC with glitches and drops (with sound until
> the end) but reencoding generally failed (silence after the first drop).
>
> How to survive? How to reencode with "ignore errors like play in vlc"?
> I tested many ffmpeg commands and tricks and nothing :/
> Anyone?
>
>
> ps. ffmpeg from git (N-118536-g4ff1d1f3d6) of course