Opened 5 years ago
Closed 5 years ago
#8375 closed defect (needs_more_info)
FFmpeg produces m4a file unplayable by portable music player
Reported by: | NSLW | Owned by: | |
---|---|---|---|
Priority: | normal | Component: | undetermined |
Version: | unspecified | Keywords: | |
Cc: | Blocked By: | ||
Blocking: | Reproduced by developer: | no | |
Analyzed by developer: | no |
Description
Summary of the bug:
FFmpeg merely copying AAC stream into new container makes the file unplayable for my portable music player.
How to reproduce:
I've got an audio file for which
ffprobe originalFile.m4a
gives
Metadata:
major_brand : M4A
minor_version : 0
compatible_brands: M4A mp42isom
My portable player recognizes it as music and is able to play it. After doing
ffmpeg -i originalFile.m4a -vn -sn -dn -acodec copy convertedFile.m4a
I get a new audio file. My portable player doesn't recognize it as music and isn't able to play it, although desktop players have no troubles playing it.
Command
ffprobe convertedFile.m4a
gives
Metadata:
major_brand : M4A
minor_version : 512
compatible_brands: isomiso2
To make it recognizable and playable on my portable player I do
MP4Box -brand M4A:0 -rb isom -rb iso2 convertedFile.m4a
Command
ffprobe convertedFile.m4a
now gives
Metadata:
major_brand : M4A:
minor_version : 0
compatible_brands: M4A mp42M4A:
It wouldn't work if I only invoked one of below commands:
MP4Box -brand M4A:0 convertedFile.m4a
MP4Box -brand M4A:0 -rb isom convertedFile.m4a
MP4Box -brand M4A:0 -rb iso2 convertedFile.m4a
MP4Box -rb isom -rb iso2 convertedFile.m4a
MP4Box -rb isom convertedFile.m4a
MP4Box -rb iso2 convertedFile.m4a
Afterwards I could call
MP4Box -brand M4A:0 -ab isom -ab iso2 convertedFile.m4a
and the file would be playable as well.
Command
ffprobe convertedFile.m4a
would then give
Metadata:
major_brand : M4A:
minor_version : 0
compatible_brands: M4A mp42M4A:isomiso2
I see two culprits here:
1) compatible_brands should contain M4A as its first entry
2) minor_version should be 0 instead of 512
Change History (4)
follow-up: 3 comment:1 by , 5 years ago
Component: | ffmpeg → undetermined |
---|---|
Version: | 4.1.4 → unspecified |
comment:3 by , 5 years ago
Replying to cehoyos:
Please test current FFmpeg git head, provide the command line you tested together with the complete, uncut console output and the model of your audio player to make this a valid ticket.
You can change both compatible brands and minor version in the source code to test if that really fixes playback.
I don't believe that something changed in git head in that matter so I believe that setting it up and patching would only waste my precious time.
I don't want to provide full console output and I think it's predictable what mp4box does with the file.
My audio player is Pentagram Vanquish VOLT.
Replying to mypopy:
Pls attach the originalFile.m4a for issue reproduce
It's copyrighted so I cannot do it, but I believe it's a standard m4a file from iTunes. MediaInfo shows
"Format profile : Apple audio with iTunes info"
I observed that it's not that particular file that causes the issue, because a file from unrelated batch causes the same issue when converted with ffmpeg.
What do you need that file for?
comment:4 by , 5 years ago
Resolution: | → needs_more_info |
---|---|
Status: | new → closed |
Please test current FFmpeg git head, provide the command line you tested together with the complete, uncut console output and the model of your audio player to make this a valid ticket.
You can change both compatible brands and minor version in the source code to test if that really fixes playback.