Xref: utzoo comp.compression:315 alt.comp.compression:204 Path: utzoo!utgpu!cs.utexas.edu!sdd.hp.com!think.com!mintaka!sparky!phillips From: phillips@sparky.mit.edu (Mike Phillips) Newsgroups: comp.compression,alt.comp.compression Subject: Re: Compression of 16-bit sound files. Message-ID: <1991Apr11.141742.13069@mintaka.lcs.mit.edu> Date: 11 Apr 91 14:17:42 GMT References: Sender: news@mintaka.lcs.mit.edu Reply-To: phillips@sparky.mit.edu (Mike Phillips) Organization: Massachusetts Institute of Technology Lines: 22 >I would like to know if there exists any good and moderately fast compression >programs that will compress 16-bit soundfiles by a large amount. These files >are stored for archiving purposes and therefore I need a non lossy compression. >I have tried compress, freeze and yabba, and I get best compression with freeze >but it take the longest time both to compress and decompress. What I would like >is a program that has equal or better compression than freeze and has faster >(preferably much faster) decompression speed. Btw this is for a Unix machine. We found that we have been able to get fairly good compression (about 50-60% for most of our data) by simply packing the numbers into less bits. So the compression program writes out a little header for chunks of speech saying "here comes X words packed into Y bits per word". This works well because much of speech is pretty quiet. It's simple, it's fast, it seems to work pretty well and it's free. You can get this via anonymous ftp from lightning.lcs.mit.edu (18.27.0.147) it's all in pub/compression/tarfile.Z Mike (phillips@goldilocks.lcs.mit.edu)