SCI/Specifications/Resource files/Decompression algorithms

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Decompression algorithms

The decompression algorithms used in SCI are as follows:

SCI0 compression algorithms
method algorithm
0 uncompressed
1 LZW
2 HUFFMAN


SCI01 compression algorithms
method algorithm
0 uncompressed
1 LZW
2 COMP3
3 HUFFMAN


SCI1.0 compression algorithms
method algorithm
0 uncompressed
1 LZW
2 COMP3
3 UNKNOWN-0
4 UNKNOWN-1
SCI1.1 compression algorithms
method algorithm
0 uncompressed
18 DCL-EXPLODE
19 DCL-EXPLODE
20 DCL-EXPLODE


As reported by Vladimir Gneushev, SCI32 uses STACpack (as described in RFC 1974) explicitly, determining whether there is a need for compression by comparing the size of the compressed data block with that of the uncompressed.