Commit Graph

623 Commits

Author SHA1 Message Date
Zoltan Szabadka
3f655b63de Fix buffer overflow bug in the brotli encoder. 2014-03-27 16:38:07 +01:00
Zoltan Szabadka
347781947a Update the dictionary and the transforms. 2014-03-25 16:48:25 +01:00
Zoltan Szabadka
e7650080a8 Updates to Brotli compression format, decoder and encoder
This commit contains a batch of changes that were made to the Brotli
compression algorithm in the last month. Most important changes:

   * Format change: don't push distances representing static dictionary words to the distance cache.
   * Fix decoder invalid memory access bug caused by building a non-complete Huffman tree.
   * Add a mode parameter to the encoder interface.
   * Use different hashers for text and font mode.
   * Add a heuristics to the hasher for skipping non-compressible data.
   * Exhaustive search of static dictionary during backward reference search.
2014-03-20 14:32:35 +01:00
Zoltan Szabadka
cddab4adef Enable the static dictionary in the Brotli decoder. 2014-03-06 17:25:43 +01:00
Zoltan Szabadka
2f268ad158 Add the initial version of the static dictionary and transforms to Brotli. 2014-02-17 14:25:36 +01:00
Zoltan Szabadka
0454ab4ec0 Updates to Brotli compression format, decoder and encoder
This commit contains a batch of changes that were made to the Brotli
compression algorithm in the last month. Most important changes:

   * Fixes to the spec.
   * Change of code length code order.
   * Use a 2-level Huffman lookup table in the decoder.
   * Faster uncompressed meta-block decoding.
   * Optimized encoding of the Huffman code.
   * Detection of UTF-8 input encoding.
   * UTF-8 based literal cost modeling for improved
     backward reference selection.
2014-02-14 15:04:23 +01:00
Zoltan Szabadka
d01c71c4ad Fix -Wconversion compiler warnings in the brotli decoder. 2014-01-08 12:34:35 +01:00
Zoltan Szabadka
2bcd58bb5a Brotli format change: small improvement to the encoding of Huffman codes
Combine the HSKIP and the simple/complex Huffman code type bits.
2014-01-08 12:28:28 +01:00
Zoltan Szabadka
e60dbdb10b Small update to brotli specification.
Clarify how to recover from error conditions caused by overflowing
block types and symbol values.
2014-01-06 16:35:24 +01:00
Zoltan Szabadka
d762bc6845 Bug fixes for the brotli encoder and decoder. 2014-01-06 16:01:57 +01:00
Zoltan Szabadka
1447345cbb Brotli format change: improved encoding of Huffman codes
This change removes the redundant HCLEN, HLENINC and HLEN
fields from the encoding of the complex Huffman codes and
derives these from an invariant of the code length sequence.
Based on a patch by Robert Obryk.
2013-12-17 17:17:57 +01:00
Zoltan Szabadka
b8a1008569 Use C-style comments in the brotli decoder. 2013-12-16 14:45:57 +01:00
Zoltan Szabadka
29bb7cb1af Fix Microsoft VisualStudio 64-bit build of brotli 2013-12-13 15:30:20 +01:00
Zoltan Szabadka
354349d7ae Fix Microsoft VisualStudio build of brotli
- Move all variable declarations to the beginning of the block
- #ifdef-out read/write calls
2013-12-13 10:39:46 +01:00
Roderick Sheeter
c23cb1e83d Support for OSX build; tested using OSX 10.9/clang-500.2.79 2013-12-12 10:43:05 -08:00
Zoltan Szabadka
60c24c0c2d Updates to Brotli compression format, decoder and encoder
This commit contains a batch of changes that were made to the Brotli
compression algorithm in the last month. Most important changes:

   * Updated spec
   * Changed Huffman code length alphabet to use run length codes more
     efficiently, based on a suggestion by Robert Obryk
   * Changed encoding of the number of Huffman code lengths (HLEN)
   * Changed encoding of the number of Huffman trees (NTREES)
   * Added support for uncompressed meta-blocks
2013-12-12 13:18:04 +01:00
Zoltan Szabadka
8d7081f2d0 Add draft specification of the brotli format 2013-11-28 17:37:13 +01:00
Roderick Sheeter
1cdcbd851f Added Brotli compress/decompress utilities and makefiles 2013-11-19 14:32:56 -08:00
Zoltan Szabadka
c6b9c7c5c8 Updates to Brotli compression format, decoder and encoder
This commit contains a batch of changes that were made to the Brotli
compression algorithm in the last three weeks. Most important changes:

  * Added UTF8 context model for good text compression.
  * Simplified context modeling by having only 4 context modes.
  * Per-block context mode selection.
  * Faster backward copying and bit reading functions.
  * More efficient histogram coding.
  * Streaming support for the decoder and encoder.
2013-11-15 19:02:17 +01:00
Zoltan Szabadka
c66e4e3e4f Add brotli compressor
This commit is for the encoder for brotli compression format.
Brotli is a generic byte-level compression algorithm.
2013-10-23 13:06:13 +02:00
Zoltan Szabadka
6455522172 Make the brotli decoder more C90-compatible.
(1) Move all variable declarations to the beginning of the block.
(2) Remove 'z' printf modifiers.
(3) Fix 'comma at the end of enumeration list' warning.
2013-10-22 15:02:54 +02:00
Zoltan Szabadka
e0346c8262 Fix name collisions with libwebp.
Prefix all externally visible function names with Brotli and
make all other functions static.
2013-10-17 12:41:36 +02:00
Zoltan Szabadka
8f30907d0f Add brotli decompressor
This commit is for the decoder for brotli compression format.
Brotli is a generic byte-level compression algorithm.
2013-10-11 10:26:07 +02:00