Short: AGF - n*8-bit Sample Pre-Packing Processor w/src Author: olethros@geocities.com (Christos Dimitrakakis) Uploader: olethros geocities com (Christos Dimitrakakis) Type: util/pack Replaces: util/pack/agf.lha Requires: 68030+fpu Architecture: m68k-amigaos OVERVIEW AGF is a sample pre-processor. It transofrms the data into a form having very little information content. This makes it easier for compression programs to pack it down to a small size. AGF combined with GZIP gives an average compression of 50% and it is always better than any other compression method on its own. It is similar to ADPCM, but better :) HISTORY 05-09-1999 : Released a version that works properly (more or less) SUMMARY AGF - Adaptive Gradient-descent FIR filter. This is a neural-network-like adaptive FIR filter. The adaptation is deterministic, which means that the sample can be recovered from the processed file without needing to save an FIR coefficients to it as well. Adaptation is done on-line, on a sample-by-sample basis. USAGE AGF MODE sample processed_sample The processed sample can then be efficiently packed with any kind of packer. I recommend xpk (xGZIP or xSQSH). lha/lzx will also do :) The results are always MUCH better. Modes: x : extract (decode) using a linear ANN c : compress (encode) using a linear ANN xd : extract (decode) using a static filter cd : compress (encode) using a static filter TODO Make an xpksublib out of it. Add options for adjusting the number of coefficients and adaptation rate. BUGS Might have problems with samples that clip a lot.. Bugs Reports to olethros@geocities.com with "AGF BUG" as the subject message please SEE ALSO see also dev/basic/gasp.lha for a similar pre-processor where the adaptive process is controlled by a Genetic Algorithm