Battlefield 1943 [XBLA] Strange Audio Format by pietastesgood at 10:03 PM EST on December 8, 2009
Hello guys,
http://www.megaupload.com/?d=LVF3BXRJ
Here is the credits theme of Battlefield 1943 for Xbox Live Arcade.
At first glance I thought it would be XMA, since the logo music was XMA. However, I could find FF blocks in the logo music file while I could not find FF blocks in this one.
After doing some research, the credits theme is just over 2 minutes (2:02) - way too short for its file size if it were XMA stereo. I plopped on a surround header, but it did not work either.
It does look slightly reminiscent of a headerless RIFF WAV file, but I'm just basing that off file sizes and the lack of FF blocks in the main audio data.
Wow, this is really bizarre. It has variable size XMA2 packets. I'll have to make a modified parser to handle this.
[edit] Rather than mutate xma_parse further, here's a separate tool to unpack the 1943 file into a normal XMA2 stream. unpack1943 0.0
Run like: unpack1943 BMUS.res BMUS.out
If it doesn't say "Done!" then it failed somewheres.
The file seems to end a little early, but every indication is that that's the way the track is. If you happen to have a way to contradict this I can look closer but I don't think the rest is there.
It seems like the size is just due to a stupid high bitrate.
edited 11:32 PM EST December 8, 2009
by pietastesgood at 11:20 PM EST on December 8, 2009
That's new, variable size. Might that be a cause for the lack of FF's or is that just an EA XMA variant (like the Ubisoft 001800 variant with no FF's)?
Yeah, there's an extra header on the packets that gives the size, so it doesn't need to use FF padding. The software has to pad this out before passing it to the hardware. Don't know why they didn't just use a larger block size, maximum is 8MB which would have handled almost this whole file with one block, though then it would all have to be in memory.