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How to detect raw ADPCM.

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Strobe
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How to detect raw ADPCM.

Post by Strobe » Wed Aug 30, 2006 4:07 pm

Ive ran some tests too analyze how different adpcm looks like,
and the conclusion is that all of them almost looks the same,
its just small differences, depending on the encoder.
(you have to see the data thru Points though, instead of the usual
line drawing most sample analyzers have, to detect this pattern.)

so, if you have an audio file with no header, that cannot be playedback
normally (like PCM), and it looks like the below picture, you most certain
are dealing with ADPCM Data.

Ive ran scans with MS-ADPCM, IMA ADPCM, Sony VAG, and then
one unknown music file from a game i had, and then i came to the conclusion
that it is actually possible to see if the data is ADPCM.
(something i didnt think was possible without actually trying to decode it).
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FunteX
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Post by FunteX » Wed Aug 30, 2006 4:31 pm

can you post some pictures of the analysis?

this topic sounds interresting... :D

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heheheh

Post by Strobe » Wed Aug 30, 2006 4:47 pm

FunteX: I did, but you must be logged in to view them, but i will post some more of them now.
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And more....

Post by Strobe » Wed Aug 30, 2006 4:48 pm

weehaaa
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Post by Mr.Mouse » Wed Aug 30, 2006 7:32 pm

Interesting way of looking at this! Now for an interpreter that can read the format of the waves, and pinpoint the type of file format used? :D

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Post by brienj » Thu Aug 31, 2006 12:04 am

Just use Cool Edit Pro or any other advanced audio editor and you can load any sound file without a header. ;)

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hmmms...

Post by Strobe » Thu Aug 31, 2006 7:00 am

brienj: I think Mr.Mouse meant a scanner that detects automatically if
the data is ADPCM =D. that would be a bit harder though !

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Post by Savage » Thu Aug 31, 2006 12:02 pm

looks nice :D

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how do i decode it

Post by jpagac » Tue Oct 17, 2006 10:18 pm

I have some adpcm audio I'm trying to play. Cooledit doesnt work. I dont think its a standard format. How can i decode it?

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