FFmpeg debug assert in analyzerqueue

[Daniel Schürmann]

A Debug debug assert fails with recent master build an FFmpeg, analyzing a m4a track:

Debug [AnalyzerQueue 1]: SoundSourceFFmpeg - readFramesToCache: Packet too big or File end
Critical [AnalyzerQueue 1]: DEBUG ASSERT: "framesRead <= framesToRead" in function bool AnalyzerQueue::doAnalysis(TrackPointer, mixxx::AudioSourcePointer) at src/analyzer/analyzerqueue.cpp:203

framesRead = 4096 and framesToRead = 1024

this cause additional follow up failing debug asserts, because we use the invalid framesRead.

[Uwe Klotz (uklotzde-deactivatedaccount)]

AnalyzerQueue should only request framesToRead instead of kAnalysisFramesPerBlock frames. On the other hand SoundSourceFFmpeg should limit the requested number of frames appropriately and only return what is actually available.

A typical example of lazy implementation meets careless caller. Both could do better to prevent these kind of errors.

[Uwe Klotz (uklotzde-deactivatedaccount)]

Fixes the calling side:
https://github.com/mixxxdj/mixxx/pull/1286

[Uwe Klotz (uklotzde-deactivatedaccount)]

New PR:
https://github.com/mixxxdj/mixxx/pull/1289

[Uwe Klotz (uklotzde-deactivatedaccount)]

Fix for AnalyzerQueue has been committed. This bug is no longer critical, although SoundSourceFFmpeg should also be fixed.

[Uwe Klotz (uklotzde-deactivatedaccount)]

...and a new API compliance test: https://github.com/mixxxdj/mixxx/pull/1291

[Uwe Klotz (uklotzde-deactivatedaccount)]

The PR now fixes SoundSourceFFmpeg.

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/8883