WHY HUFFMAN ENCODING ?
- No Patent Problems: Dictionary compression and
arithmetic compression are both areas of legal problems over patents.
- Fast: Static Huffman compression is much faster
for both coding and decoding than arithmetic compression. (See
"Lossless Compression for Text and Images", A Moffat, T C Bell, and
I H Witten, in "Signal Compression: Coding of Speech, Audio, Text, Image,
and Video", published by World Scientific Publishing, page 195-196, 1997.)
- Practical: The compression algorithm comparisons
shows that the Huffman based algorithms give good compression in a
reason time.
- Very Close to Optimum: Whilst Huffman encoding must
assign an integer number of bits to every symbol, this is not a
limitation to compression ratios in almost all practical cases.
- Static Algorithm: The coding table can be produced
once and used for many images with the same statistical characteristics,
to avoid the need of calculating image statistics and symbol codes.
- Entry Look-Up Table: Since very pixel is coded
by 1 of more bits, if predictor 1 is used, a simple look-up table may
be defined between pixel position in the array and bit position in the
compressed data.