We've calculated an approximate values in the table. Here's the first output. The red points are where the wave gets wrong, because the values are not accurate.

Each adpcm block has some 5-bit value. We are trying to find out what can it be. An index for some table, or just a scale?



It seem to correspond the original waveform posted on the top

This is a comparison between the decoded first samples of each frame and same sound recorded from youtube. We can now try and guess where the sample shifts go to decode the whole frames.

OrangeC wrote:Interesting stuff. So how did you manage to get the MTA2 samples playing when you did the swap thing?

Easily. They are all just a stream of 64 sample-blocks. You can replace them all you want.

GHzGangster wrote:I did some debugging...

We actually don't need debugging. We just need ADPCM tables for this codec.

I didn't decode the first sample. It is saved in the ADPCM block unchanged. This is what I wanted to check and it was successful.

OrangeC wrote:Here is an MTAF file.

ok, it is really different. 128 samples instead of 64 in MTA2, and probably another algorithm. I will keep you informed. bgm_mgo_lobby01.bgm has 12-channel streams. Weird. Maybe that are 3 parts of one 4-channel music track.

OrangeC wrote:EDIT: Also NOTE that the decoding algorithm for MTAF is inside the vgmstream.dll but I cannot find source code or a decompiled version of it from hcs.

Yes I found his source, but now we need to know how different is MTA2 from MTAF. It may be very different.

One user asked me if I can look at the sounds from Metal Gear Solid 4. So I checked bgm_mgo_title01.bgm and it looks like 4-channel audio encoded as ADPCM of some kind. 64-sample blocks. If we take first (uncompressed) samples from each block, this is the picture: http://oi61.tinypic.com/10wjixj.jpg...

The format in Medal of Honor 2010 reboot is similar, but different headers, and most sounds are in Ealayer3 version 5. Yet some are still in XAS. I can decode them all I think.

Vosvoy wrote:I saw that in the Xbox360 version but it was very messy. Each samples didn't have the right sample rate and the loop was cut before the end. I'm happy you figured out.

Yes, if I combine these pieces one by one, can hear a perfect music file.

I've got the music decoded. In each music bank there are about 100-200 audio files. Some are complete music pieces, but most are short fragments, combining which you can compile music tracks, or loop them infinitely. There must be some script in the game to do this, but currently I can't find it or ...

OrangeC wrote:let me know when music is supported so i can test MOH reboot pc.

The format in that "reboot" may be totally different, so you better send me a sample of its music bank.

Vosvoy wrote:PS: I don't think you can post stream info file mate but I'm not 100% sure of that.

Ok, I removed them.

Audio extractor for Medal of Honor Currently only tested on "Medal of Honor: Airborne" and "Medal of Honor 2010" but may work with other EA games with Unreal Engine. Medal of Honor: Airborne If you unpack .xxx packages with Gildor's extractor you get a lot of files of type .SoundRiotRawAsset. Some o...

Ok, tools uploaded. Have fun :) It is strange, but many .xxx files have strange (encrypted?) part in the beginning. Different size, but all about 32k. Interesting that first 31184 bytes of those are the same for all .xxx files. It doesn't affect the unpacking process, but what could that be? Any ide...