Unsupported mp3s

[jnordberg]

I'm having issues with loading some mp3 files where load_mp3 just returns a zero sampling rate and an empty array. I've tried re-encoding to different bitrates using ffmpeg but same issue. The demo mp3 in this repository works fine...

Are there known limitations to mp3 formats/features supported?

[neonbjb]

I don't know of any issues like this, would you mind attaching an example?

[jnordberg]

Here's an example short.mp3.zip, it's an excerpt from a much longer file but still have the same loading problem.

I've found that re-encoding my files with pydub allows them to be loaded with fastmp3, the pydub versions are also significantly smaller with no difference in codec settings (at least what I can see in VLC).

Working re-encoded version: short_pydub.mp3.zip

[neonbjb]

Hmm. If I do ffprobe on both of these files, the only difference that shows up is an "XMP header". If I open up short.mp3 in a text editor, you can see where all the extra file size is: there is a huge XML document embedded within the file that appears to be an "XMP" format. My guess is that is what is causing this issue.

Lets leave this open so I can dig in a little bit when I have time. It may not be practical to fix this (I do not have the technical know-how to make fixes to pyminimp3), but I should at least identify the issue when it happens and print out a more descriptive error.

[jnordberg]

Interesting, I can confirm that removing that XMP metadata field resolves the issue.

In case anyone else is having this issue here's how to remove all metadata from an mp3 with ffmpeg:

ffmpeg -i short.mp3 -map_metadata -1 -c:a copy short_nometa.mp3