Batch change Divx to Xvid (FourCC+Writing library+unpack bitstream)

[SmurfRecorder]

Hello. I'd like to change parameters of multiple AVI files at once to make them playable.
My current workflow on single file:
1. MPEG4Modifier - packed bitstream unpack
2. MPEG4Modifier change user data (Writing library from something like DivX503b2682p to XviD0069
3. Visual AVI FourCC Changer (https://sourceforge.net/projects/vsfccchanger/) - change fourCC - this works for all files

And I know I can do steps 1 and 3, e.g with FFMPEG with stream copy, but I'm not sure how to automatize step 2

this command did not change writing library:

ffmpeg -i input.avi -vtag XVID -bsf:v mpeg4_unpack_bframes -c:v copy -c:a copy output.avi

[ProWo]

Hello. I'd like to change parameters of multiple AVI files at once to make them playable.
My current workflow on single file:
1. MPEG4Modifier - packed bitstream unpack
2. MPEG4Modifier change user data (Writing library from something like DivX503b2682p to XviD0069
3. Visual AVI FourCC Changer (https://sourceforge.net/projects/vsfccchanger/) - change fourCC - this works for all files

And I know I can do steps 1 and 3, e.g with FFMPEG with stream copy, but I'm not sure how to automatize step 2

this command did not change writing library:

ffmpeg -i input.avi -vtag XVID -bsf:v mpeg4_unpack_bframes -c:v copy -c:a copy output.avi

Try instead this single commandline:

ffmpeg -i source.avi -c copy -bsf:v mpeg4_unpack_bframes -vtag FMP4 source_fixed.avi

[SmurfRecorder]

But this just change fourCC not "writing library"
after that command ffmpeg Mediainfo shows:

Codec ID                                 : FMP4
Writing library                          : DivX 2682

when editing with MPEG4Modifier I get

Writing library                          : XviD 69

And this file works correctly for me

[ProWo]

But this just change fourCC not "writing library"
after that command ffmpeg Mediainfo shows:

Codec ID                                 : FMP4
Writing library                          : DivX 2682

OK, but this file is playable or not?

when editing with MPEG4Modifier I get

Writing library                          : XviD 69

And this file works correctly for me

The “writing library” is just an information tag and should not affect the video's playback

[SmurfRecorder]

Unfortunately the file is unplayable until I change writing library... This is LG Oled 4k TV bought about 2021.

[cholla]

I worked on this & part of the problem is the .avi container.
It has limits on what can be written to in it's metadata.
I was never able to get the metadata to accept "Writing library".
What I got was "Writing application" in MediaInfo.

Give this code a try:

ffmpeg -i input.avi -flags +bitexact -fflags +bitexact -map_metadata -1 -metadata:g "ISFT=XviD 69" -metadata:g "encoding_tool=XviD 69" -metadata title="movie name" -c copy output.avi