Rockbox mail archive
Subject: Wavpack Hybrid Status Update
Wavpack Hybrid Status Update
I'm a little behind this week -_-.
I started writing a multifile buffering interface allowing a codec to
devote flexible fractions of its buffer space to different files.
Halfway through this, paranoia struck: I never CHECKED that the audio
coming out of the codec I implemented last week was lossless!
I searched for some way to easily compare audio files but didn't find
one matching what I wanted, so I wrote my own:
http://www.q3q.us/wavdiff.c . This program dumps the headers from WAV
files and then compares them sample by sample, reporting any samples
that don't match.
I then went and double- and triple- checked the output from my codec.
Turns out I'd forgotten a ten-line code chunk so all Wavpack blocks
(except the first one, which I'd checked last week!) were decoding
incorrectly and falling back to hybrid lossy. This is fixed and I also
made a few improvements to the codec itself. As they say, you're only
paranoid if the world isn't out to get you :-P.
The updated version, which produces files 100% identical to those spat
out by wvunpack, is at:
This still can only run on the PC, not a real target. Since I'm well
on my way to having a better buffering interface, I should be able to
have at least sim builds playing sweet lossless sound by the end of
Received on 2009-06-21
Page was last modified "Jan 10 2012" The Rockbox Crew