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| author | Björn Gustavsson <[email protected]> | 2014-01-22 16:19:32 +0100 |
|---|---|---|
| committer | Björn Gustavsson <[email protected]> | 2014-01-22 16:19:32 +0100 |
| commit | e99633a51cbd22b16606c2669c575c22cf1c511f (patch) | |
| tree | 784ef6b3eec7461e7b8962fee2d1ba6858b516b6 /erts/doc | |
| parent | 990b655c92f889d2c45e6f43ee6fdae29ffc8464 (diff) | |
| parent | 9f57d8c4f86323cf7481c9a7e512486087bb5542 (diff) | |
| download | otp-e99633a51cbd22b16606c2669c575c22cf1c511f.tar.gz otp-e99633a51cbd22b16606c2669c575c22cf1c511f.tar.bz2 otp-e99633a51cbd22b16606c2669c575c22cf1c511f.zip | |
Merge branch 'bjorn/erts/zlib-1.2.8'
* bjorn/erts/zlib-1.2.8:
configure: Prefer the system's zlib over own our zlib source
Update preloaded modules
Add the 'rle' zstrategy
Don't make gzio.c dependent on the zutil.h header file
Update zlib to 1.2.8
erts/zlib: Remove unused file example.c
Diffstat (limited to 'erts/doc')
| -rw-r--r-- | erts/doc/src/zlib.xml | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/erts/doc/src/zlib.xml b/erts/doc/src/zlib.xml index afc597b729..11a7437f5a 100644 --- a/erts/doc/src/zlib.xml +++ b/erts/doc/src/zlib.xml @@ -161,20 +161,22 @@ list_to_binary([Compressed|Last])</pre> state. <c><anno>MemLevel</anno></c>=1 uses minimum memory but is slow and reduces compression ratio; <c><anno>MemLevel</anno></c>=9 uses maximum memory for optimal speed. The default value is 8.</p> - <p>The <c><anno>Strategy</anno></c> parameter is used to tune the - compression algorithm. Use the value <c>default</c> for - normal data, <c>filtered</c> for data produced by a filter - (or predictor), or <c>huffman_only</c> to force Huffman - encoding only (no string match). Filtered data consists - mostly of small values with a somewhat random - distribution. In this case, the compression algorithm is - tuned to compress them better. The effect of - <c>filtered</c>is to force more Huffman coding and less - string matching; it is somewhat intermediate between - <c>default</c> and <c>huffman_only</c>. The <c><anno>Strategy</anno></c> - parameter only affects the compression ratio but not the - correctness of the compressed output even if it is not set - appropriately.</p> + <p>The <c><anno>Strategy</anno></c> parameter is used to tune + the compression algorithm. Use the value <c>default</c> for + normal data, <c>filtered</c> for data produced by a filter (or + predictor), <c>huffman_only</c> to force Huffman encoding + only (no string match), or <c>rle</c> to limit match + distances to one (run-length encoding). Filtered data + consists mostly of small values with a somewhat random + distribution. In this case, the compression algorithm is tuned + to compress them better. The effect of <c>filtered</c>is to + force more Huffman coding and less string matching; it is + somewhat intermediate between <c>default</c> and + <c>huffman_only</c>. <c>rle</c> is designed to be almost as + fast as <c>huffman_only</c>, but give better compression for PNG + image data. The <c><anno>Strategy</anno></c> parameter only + affects the compression ratio but not the correctness of the + compressed output even if it is not set appropriately.</p> </desc> </func> <func> |