Anyone know if it's possible to extract Loom's CDDA.SOU? |
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apprentice_fu
Joined: 23 Dec 2010
Posts: 11
Location: Germany |
As my previous post was a bit vague:
The offset at the start of the file seems to be 800 bytes (or 800 + x*1177)
With stereo, 8-bit, 44100 Hz and 13.33 ms you get 1176 bytes audio data + 1 byte shifting info. The shifting info is at the start of such a
The lower four bits of the shifting info (info & 0xf) are for the right channel the higher four (info >> 4) are for the left channel.
At the beginning of the file there are some bytes (0x10 up to 0x1f) which I can't make sense of.
(edit corrected bits to bytes)
Last edited by apprentice_fu on Sun Feb 02, 2014 6:37 pm; edited 1 time in total
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Wed Jan 12, 2011 4:32 am |
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icanntspell

Joined: 18 May 2009
Posts: 93
Location: The Netherlands |
Thanks a lot, great work! I managed to build a working decoder with this info. It took me some time to realize it was encoded in signed pcm. I am not really an audio guy as well.
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Sun Nov 13, 2011 7:50 pm |
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jepael
Joined: 25 Oct 2008
Posts: 26
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quote: Originally posted by apprentice_fu
With stereo, 8-bit, 44100 Hz and 13.33 ms you get 1176 bytes audio data + 1 byte shifting info.
The 1176 is an interesting value, as one audio CD sector contains 1176*2=2352 bytes of 16-bit stereo data. It may be that the game internally uses cd-rom sector numbers or the minute:second:frame format when it starts playing the audio. There are 75 frames (audio sectors) per second.
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Tue Nov 15, 2011 7:35 am |
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clone2727
Retired

Joined: 09 Jun 2006
Posts: 1592
Location: NJ, USA |
quote: Originally posted by jepael The 1176 is an interesting value, as one audio CD sector contains 1176*2=2352 bytes of 16-bit stereo data. It may be that the game internally uses cd-rom sector numbers or the minute:second:frame format when it starts playing the audio. There are 75 frames (audio sectors) per second.
Of course it references the audio data that way; they didn't actually change the SCUMM data from the CD version. In Loom's case, it specifies offset from the beginning of the disc (see scumm/script_v5.cpp:2612).
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Tue Nov 15, 2011 1:08 pm |
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dtungsten
Joined: 03 Feb 2014
Posts: 1
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quote: Originally posted by icanntspell Thanks a lot, great work! I managed to build a working decoder with this info. It took me some time to realize it was encoded in signed pcm. I am not really an audio guy as well.
I managed to build a working decoder too, thanks!
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Tue Feb 04, 2014 10:38 pm |
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