Take a WAV file in WAVE_FORMAT_EXTENSIBLE format with wValidBitsPerSample == 20 and wBitsPerSample == 24.
Compress it to FLAC or Wavpack (cmdline encoders).
fb2k cannot verify integrity of such files: it crashes. No problems with the original WAV file though.
This is most interesting, thanks for the report.
On the other hand, fb2k doesn't crash if wBitsPerSample == 24 and wValidBitsPerSample == 16.
AND: FLAC calculates MD5 of such files differently than WavPack, TAK (http://www.hydrogenaudio.org/forums/index.php?s=&showtopic=54087&view=findpost&p=827368) and OFR. (I wrote about it: http://www.hydrogenaudio.org/forums/index....st&p=827385 (http://www.hydrogenaudio.org/forums/index.php?s=&showtopic=99757&view=findpost&p=827385) )
I took Garbage sample from this thread (http://www.hydrogenaudio.org/forums/index.php?showtopic=78476) and converted it to 3-bit pcm so it's possible to test various BitsPerSample / ValidBitsPerSample combinations: [attachment=7432:wValidBitsPerSample.7z]
fb2k 1.2.4 b1 doesn't crash but it doesn't cover some exotic cases (the result is MD5 mismatch for WavPack and Unsupported format or corrupted file for FLAC)
Thanks for the detailed report.
FLAC with bit depth below 8 = fixed for the next update after 1.2.4 beta 3.
Exotic cases of WavPack bit depth configs (with 8 or more bits wasted) currently fail checksumming, I'll need to add special handling for these.