[flac-dev] FLAC 1.3.0pre3 NOT lossless

[Martijn van Beurden]

On 15-04-13 17:54, Marcus Johnson wrote:
> the audio was also 192,000khz sample rate, forgot to mention that, adn 
> here are the audio files, the original, the flac, and the decoded from 
> flac.
>
> the archive is 7zip, Idk where to upload it so I'll just send it to 
> depositfiles.

As far as I can see, these audio files are lossless and the WAV files 
are identical when regarding only audio data. When I open both in 
Audacity and invert one of them, the channels cancel each other exactly, 
so the audio data must be the same.

The checksums don't have to match because WAV is a complicated standard 
and FLAC might be writing the file a little different (see for example 
http://xiph.org/flac/faq.html#tools__two_bytes_short) FLAC compresses 
the audio data losslessly, not the WAV file itself, that's why simple 
MD5-summing doesn't cut it.

The FLAC file is small and encoding is very fast because most of the 
file is silence, which is very easy to encode.