Commit Graph

20 Commits

Author SHA1 Message Date
Lode Vandevenne
fee303fd87 fix brotli decoder MSVC compilation error 2015-08-10 14:18:37 +02:00
Lode Vandevenne
94cd7085f7 brotli decoder performance improvements 2015-08-10 13:35:23 +02:00
Lode Vandevenne
bad0f4edf1 Brotli Bug Fixes 2015-06-26 17:37:00 +02:00
Zoltan Szabadka
b43df8f699 Brotli custom LZ77 dictionary support.
Adds functions to prepend such dictionary to the
encoder and decoder, and twiddles their internal
parameters to do as if that was a previous part of
the input. This dictionary is just a prefilled LZ77
window, it is not related to the built in transformable
brotli dictionary.
2015-06-12 15:43:54 +02:00
Zoltan Szabadka
641bc15882 Speedups and fixes to the decoder.
* Read data by 4-byte runs.
    This resolves unaligned read (Bus error) on arm-android.

  * Get rid of malloc/free in BrotliBuildHuffmanTable.

  * Tweak order of instructions when reading Huffman codes.
2015-06-12 15:12:23 +02:00
Zoltan Szabadka
bef6938af7 Restrict the ARM optimizations to little endian architectures. 2015-05-07 20:36:35 +02:00
Zoltan Szabadka
f3e71e441e Fix 32bit build. 2015-05-07 19:45:21 +02:00
Zoltan Szabadka
5f39d607ef Decoder optimizations for ARM architecture. 2015-05-07 17:10:27 +02:00
Zoltan Szabadka
83aa24dc86 Speed and memory usage improvements for the decoder.
* Change order of members of bit reader state structure.

* Remove unused includes for assert. Add BROTLI_DCHECK
  macros and use it instead of assert.

* Do not calculate nbits in common case of ReadSymbol.

* Introduce and use PREDICT_TRUE / PREDICT_FALSE macros.

* Allocate less memory in the brotli decoder if it knows
  the result size beforehand. Before this, the decoder
  would always allocate 16MB if the encoder annotated the
  window size as 22 bit (which is the default), even if the
  file is only a few KB uncompressed. Now, it'll only
  allocate a ringbuffer as large as needed for the result file.
  But only if it can know the filesize, it's not possible
  to know that if there are multiple metablocks or too large
  uncompressed metablock.
2015-05-07 16:53:43 +02:00
Lode Vandevenne
8270250b40 support for partial input (streaming) 2015-03-20 16:13:15 +01:00
Lode Vandevenne
81cb09f1b3 separate the licenses from documentation 2015-03-20 15:44:15 +01:00
Zoltan Szabadka
6da0c5c992 Implement a 32-bit bitstream decoder.
The 64-bit bitstream decoder seems to have portability problems
with emscripten/asm.js as it does not compile into working code.
2015-02-25 13:32:17 +01:00
Zoltan Szabadka
4278934e82 Fix undefined behavior in decoder.
Use memmove() for copying overlapping buffers.
2014-11-26 10:37:33 +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
b8a1008569 Use C-style comments in the brotli decoder. 2013-12-16 14:45:57 +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
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
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
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