36 lines
1.5 KiB
Markdown
36 lines
1.5 KiB
Markdown
uzlib - Deflate/Zlib-compatible LZ77 compression library
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======================================================
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This is a heavily modified and cut down version of Paul Sokolovsky's
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uzlib library. This library has exported routines which
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- Can compress data to a Deflate-compatible bitstream, albeit with lower
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compression ratio than the Zlib Deflate algorithm as a static Deflate Huffman
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tree encoding is used for bitstream). Note that since this compression is
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in RAM and requires ~4 bytes per byte of the input record, should only be
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called for compressing small records on the ESP8266.
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- Can decompress any valid Deflate, Zlib, and Gzip (further called just
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"Deflate") bitstream less than 16Kb, and any arbitrary length stream
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compressed by the uzlib compressor.
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uzlib aims for minimal code size and runtime memory requirements, and thus
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is suitable for embedded systems and IoT devices such as the ESP8266.
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uzlib is based on:
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- tinf library by Joergen Ibsen (Deflate decompression)
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- Deflate Static Huffman tree routines by Simon Tatham
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- LZ77 compressor by Paul Sokolovsky provided my initial inspiration, but
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I ended up rewriting this following RFC 1951 to get improved compression
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performance.
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The above 16Kb limitation arises from the RFC 1951 use of a 32Kb dictionary,
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which is impractical on a chipset with only ~40 Kb RAM avialable to
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applications.
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The relevant copyright statements are provided in the source files which
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use this code.
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uzlib library is licensed under Zlib license.
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