Author Topic: MO3 lossless compression.  (Read 11701 times)

Cobra

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MO3 lossless compression.
« on: 20 May '05 - 18:12 »
There ( http://www.7-zip.org/sdk.html ) is LZMA algo SDK. LZMA is an all-purpose, lossless compression algorithm used in WinRAR/WinACE/7-ZIP

So you can alter MO3 to use LZMA if not used already. It can be used to replace current algo -
Quote
Lossless compression
Samples that don't compress well with MP3/OGG encoding can still be reduced in size with the lossless codec

Ian @ un4seen

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Re: MO3 lossless compression.
« Reply #1 on: 21 May '05 - 18:36 »
I had a brief look at the code, and it doesn't appear to have any specific tuning for PCM sample data? The code would also be somewhat bigger and slower (the MO3 lossless decoders are about 100 bytes).

Cobra

  • Posts: 8
Re: MO3 lossless compression.
« Reply #2 on: 21 May '05 - 20:55 »
Ahem, not for PCM (sample/instrument) data, but for rest of data...

Keltic Danor

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Re: MO3 lossless compression.
« Reply #3 on: 22 May '05 - 00:30 »
If its bigger and slower for the pcm side, then the size increase would probably either make the resulting mo3 larger, or make the difference negligible.

Cobra

  • Posts: 8
Re: MO3 lossless compression.
« Reply #4 on: 22 May '05 - 11:18 »
For samples: multimedia codec
For rest of module: LZMA

So 2 codecs.

BTW. Which codec MO3 uses now ?

Ian @ un4seen

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Re: MO3 lossless compression.
« Reply #5 on: 22 May '05 - 15:28 »
Ahem, not for PCM (sample/instrument) data, but for rest of data...

Why did you quote the "Samples...can still be reduced in size with the lossless codec" bit then? ;)

Regarding 7zip'ing the structures, that may well improve ratios a bit... I'll look into it, and see if it'd be worth the code size increase (the MO3 structure decoder is also tiny).

Poisionous_RePTiLe

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Re: MO3 lossless compression.
« Reply #6 on: 24 Dec '05 - 13:16 »
Lossless compression of _not_ the samples,
but the rest of the module-data?

Lossless compression is a term used for Sound Or Video Compression (Most often sound) which means that you
"compress", remove parts of the sound/video which is
impossible to hear/see anyways - which means that you
decrease the file-size withouth losing anything...

When it comes to data (Not sound/video) it's quite pointless,
to not say impossible, to "compress" (in reality remove) parts of it in this fashion - since any little lost information counts when it comes to 1 and 0's..

/P. RePTiLe :)

Zarggg

  • Posts: 1242
Re: MO3 lossless compression.
« Reply #7 on: 24 Dec '05 - 13:32 »
Lossless compression is a term used for Sound Or Video Compression (Most often sound) which means that you
"compress", remove parts of the sound/video which is
impossible to hear/see anyways - which means that you
decrease the file-size withouth losing anything...

Not true at all. "Lossless" compression means that nothing is removed from the resulant decompressed data stream.

You are actually describing "lossy" compression.

http://en.wikipedia.org/wiki/Lossless_data_compression
http://en.wikipedia.org/wiki/Lossy_data_compression