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- ************************************************************************
- Steve Krenek's Compressed Digital Audio
- featuring 4:1 compression
- Copyright (c) 1993 Steve Krenek
- ************************************************************************
-
- LICENSE AGREEMENT:
- This a shareware product and may be freely distributed as long as
- the following conditions are followed:
- * the program is not modified in any way,
- * all files herein are distributed together,
- * only a nominal amount is charged for providing copies.
- If you use this program, please become a registered user.
- Use the accompanying order.txt, or send $15 (+$3 shipping & handling) to:
-
- Steve Krenek
- 10803 Kinghurst, Suite 255
- Houston, TX 77099
-
-
- This program is available as a library for incorporation into your
- own program. The current version supports Microsoft C. The source
- code is also available for those wish to make additional modifications.
- Library $49
- with Source $99
-
- ***************************************************************************
- USAGE:
-
- Compression: comp file.voc file.cda
-
- Decompression: decomp file.cda <file.voc>
- (If no file.voc is given, the .cda file will play.)
-
- ***************************************************************************
- A Note to users:
-
- If there are any questions or problems (if you have problems with a
- particular file, please include a copy of that file with the desciption
- of the problem), please let me know.
-
- And if there are program enhancements you would like to see
- (other sound file formats, support for other compilers, more functions,
- documentation improvements), please let me know that too.
-
- I can be reached by writing to the above address, or on Compuserve
- at 70404,573. (Including your registration number is appreciated and
- gets you a higher priority response!). Thanks for your support.
-
- Steve Krenek
-
-
- **************************************************************************
- Program Notes
-
- This program uses ADPCM (Adaptive diffrential Pulse Code Modulation)
- to compress uncompressed 8-bit digital data in .VOC format files. The
- raw data is compressed by a factor of 4:1 (each byte is stored in 2-bits).
- However, after every 15 bytes a scale factor (the adaptive part), so
- overall compression of raw data is 3.75:1. Also, the .VOC format has some
- overhead and may contain some previously compressed data, which is not
- further compressed, so typical files are compressed by a factor of
- 3.5 - 3.7:1.
-
-
-