Error when creating 24/96 or 24/192 FLAC files, with both fb2k and the official encoder Options

[Cynic]

foobar2000's FLAC encoder creates invalid files when compressing the "warbles-*.wav" files from Monty's article, while the official encoder makes apparently OK files that pass the integrity test but are actually 4 samples longer than the uncompressed sources.

I've read this old thread but if I understood it correctly back then the problem was the outdated decoder at the time of the 1.2 release. Using the -keep-foreign-metadata switch with the official encoder will output an error about an invalid wave file and not compress anything. So it seems the problem lies in the source files but I don't know how likely it is for users to encounter a similar situation with their music and at the moment foobar2000 reports the conversion as successful despite producing unusable files.

[kode54]

The length fields for the files' main "RIFF" chunks is 12 bytes less than the actual sizes of the files. A proper RIFF parser which takes that size into account would thus truncate any data past that point. Of course, it could just decide to reject the files altogether since the specified length of the data chunk is too long for the data accepted. 12 bytes comes out to 4 24-bit samples.

Possible explanation is that whatever wrote those files did not take the size of the "fact" chunks into account when writing the size to the header, since that's the only chunk which comes to to exactly 12 bytes including its id and length fields.

You can fix it for foobar2000, and for any other proper RIFF parser, by opening the files in a hex editor and incrementing the little-endian 32-bit length field, at offset 4, by 12.

[lvqcl]

1) foobar2000 doesn't have its own FLAC encoder; it uses flac.exe.

2) "official" flac.exe doesn't work properly with 24-bit mono files. Updated encoder is available here: http://www.foobar2000.org/encoderpack