How to relate Analyzer Warnings to the files which caused them and how to fix?

When running “Analyze entire Crate” it works, but I do get warnings on the CLI (see example below).

Questions:

  • How to pinpoint the files which causes these warnings, as I don’t see a hint like a file name?
  • What’s the meaning of “Recoverable MP3 header decoding error: lost synchronization” and how to fix it? Edit or change the MP3 Tags?
Warning [AnalyzerThread 0 #5]: SoundSourceMp3 - MP3 frame header | layer: 0 mode: 0 #channels: 1 #samples: 36 bitrate: 0 samplerate: 0 flags: "0x0000"
Warning [AnalyzerThread 5 #10]: SoundSourceMp3 - Recoverable MP3 header decoding error: lost synchronization
Warning [AnalyzerThread 5 #10]: SoundSourceMp3 - MP3 frame header | layer: 0 mode: 0 #channels: 1 #samples: 36 bitrate: 0 samplerate: 0 flags: "0x0000"
Warning [AnalyzerThread 1 #7]: SoundSourceMp3 - Recoverable MP3 header decoding error: lost synchronization
Warning [AnalyzerThread 1 #7]: SoundSourceMp3 - MP3 frame header | layer: 3 mode: 2 #channels: 2 #samples: 36 bitrate: 32000 samplerate: 44100 flags: "0x0048"
Warning [AnalyzerThread 2 #6]: SoundSourceMp3 - Recoverable MP3 header decoding error: lost synchronization
Warning [AnalyzerThread 2 #6]: SoundSourceMp3 - MP3 frame header | layer: 0 mode: 0 #channels: 1 #samples: 36 bitrate: 0 samplerate: 0 flags: "0x0000"

My environment:

  • Mixxx 2.3.1
  • Ubuntu 20.04.3

Any hints or suggestions welcome, thanks!

This is common for many MP3 files, depending on how they have been encoded. We just log what the (legacy) MP3 decoder powered by libmad reports. Don’t worry, just ignore these Recoverable warnings.

Decoding with FFmpeg would be more robust, but we didn’t switch yet.

@tapir Thanks a lot for your prompt, detailed and comprehensive response, appreciated!

I’m relieved these warnings have no serious impact! :relieved:

But even if these kind of warnings could be ignored, for others it would be useful to include the name of the file which triggered it in the warning itself, wouldn’t it?

As I’m currently watching more closely what is logged :wink: I’ve noticed some other warnings (see examples below), which are obviously not related to the MP3 decoder but to the OGG / OPUS decoder.

Here again the questions: Something to worry about? How to fix it? How to pinpoint the files which triggered these warnings?

Warning [CachingReaderWorker 2]: SoundSourceOpus - Failed to read sample data from OggOpus file: 0
Warning [CachingReaderWorker 2]: AudioSource - Failed to read sample frames: expected = [14393344 → 14401008) , actual = [14393344 → 14400648)
Warning [CachingReaderWorker 1]: SoundSourceOpus - Failed to read sample data from OggOpus file: 0
Warning [CachingReaderWorker 1]: AudioSource - Failed to read sample frames: expected = [11149312 → 11154288) , actual = [11149312 → 11153928)
Warning [CachingReaderWorker 1]: SoundSourceOpus - Failed to read sample data from OggOpus file: 0
Warning [CachingReaderWorker 1]: AudioSource - Failed to read sample frames: expected = [11862016 → 11867208) , actual = [11862016 → 11866248)

Thanks a lot in advance!

The context (= file name) should be unambiguous from the preceding info logs. We don’t log the whole context everywhere, although here it would be available for logging.

The OPUS decoding errors look suspicious. Could you provide a download link to such a file via private message?