HydrogenAudio

Lossy Audio Compression => Other Lossy Codecs => Topic started by: Leftos on 2012-08-01 13:08:00

Title: Trying to decode a (possibly) 8-bit fixed-point AU file
Post by: Leftos on 2012-08-01 13:08:00
I'm trying to extract audio from a game I own, to maybe be able to listen to it outside of the game, or replace the audio with something of my own.

The company that makes the game has gone lengths to hide what the audio is encoded in, but by looking at the hex data I'm pretty sure that it's multiple audio parts, all encoded in 8-bit fixed-point, sampled at 44100Hz. This is consistent with previous iterations of the game, but it seems that the company has gone from 8-bit unsigned PCM to 8-bit fixed point, which seems that nor Audacity nor Adobe Audition have as available options for import.

The clue is a long
Code: [Select]
000000000000000000000000000000000000000000000000
hex which separates parts of the file and appears 38 times in the file, along with a header of 32-bit unsigned integers similar to this one:
Code: [Select]
02000000 CD050000 0A000000 44AC0000 00C00600

The first 4 parts of the header are consistent (channels, ?, 10 (encoding type), 44100 sampling rate) and the last one I'm guessing is data length, since it's the only one that's changing.

Am I just pulling stuff out of thin air, or am I close to something?

P.S. The header isn't consistent with the order mentioned in Wikipedia (http://en.wikipedia.org/wiki/Au_file_format (http://en.wikipedia.org/wiki/Au_file_format)), but the developers could have easily made their own header.
P.S.2 Here's the tutorial of the last game's iteration of which the audio files we could understand: http://forums.nba-live.com/viewtopic.php?f=119&t=68166 (http://forums.nba-live.com/viewtopic.php?f=119&t=68166)
Title: Trying to decode a (possibly) 8-bit fixed-point AU file
Post by: greynol on 2012-08-01 15:28:35
You are asking our members to violate this forum's terms of service.

This discussion will now close.