readme.txt

The two C source files in this archive are specific to the TRS-80 Model 4 with high-resolution grap

21-Dec-93


The two C source files in this archive are specific to the TRS-80 Model 4 with
high-resolution graphics board.  However, the code which performs Huffman enco-
ding and decoding is of general interest.

PLEASE NOTE that because TRS-80 /HR files are of a known size (19,200 bytes),
these programs do not require a character count in the Huffman header.  In a
more general application, it is suggested that either a total character count
be added to the header to be read into a variable, or that the 256 individual
character counts be summed, and the sum held in that variable.  Then, where
"19200" appears in the unhuf.c code, it should be replaced by that variable.

ALSO NOTE that character counts are stored as signed short (16-bit) integers. 
You may wish to use unsigned shorts, or even longs, if the files to be com-
pressed can be larger than 32767 or 65535 bytes.

Both dohuf.c and unhuf.c are copyright 1993, J.F.R. Slinkman.  No portion of
either may be used for commercial purposes without specific, written permission
of the author.  A limited blanket license for individual, non-commercial use is
hereby granted.


J.F.R. "Frank" Slinkman
[e-mail]