kc3-lang/brotli/c/enc/block_encoder_inc.h

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• Hash : 35e69fc7
  Author :
  Date : 2018-02-26T09:04:36
  

  New feature: "Large Window Brotli" (#640)
  
  * New feature: "Large Window Brotli"
  
  By setting special encoder/decoder flag it is now possible to extend
  LZ-window up to 30 bits; though produced stream will not be RFC7932
  compliant.
  
  Added new dictionary generator - "DSH". It combines speed of "Sieve"
  and quality of "DM". Plus utilities to prepare train corpora
  (remove unique strings).
  
  Improved compression ratio: now two sub-blocks could be stitched:
  the last copy command could be extended to span the next sub-block.
  
  Fixed compression ineffectiveness caused by floating numbers rounding and
  wrong cost heuristic.
  
  Other C changes:
   - combined / moved `context.h` to `common`
   - moved transforms to `common`
   - unified some aspects of code formatting
   - added an abstraction for encoder (static) dictionary
   - moved default allocator/deallocator functions to `common`
  
  brotli CLI:
   - window size is auto-adjusted if not specified explicitly
  
  Java:
   - added "eager" decoding both to JNI wrapper and pure decoder
   - huge speed-up of `DictionaryData` initialization
  
  * Add dictionaryless compressed dictionary
  
  * Fix `sources.lst`
  
  * Fix `sources.lst` and add a note that `libtool` is also required.
  
  * Update setup.py
  
  * Fix `EagerStreamTest`
  
  * Fix BUILD file
  
  * Add missing `libdivsufsort` dependency
  
  * Fix "unused parameter" warning.
  

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• c/enc/block_encoder_inc.h

• /* NOLINT(build/header_guard) */
  /* Copyright 2014 Google Inc. All Rights Reserved.
  
     Distributed under MIT license.
     See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
  */
  
  /* template parameters: FN */
  
  #define HistogramType FN(Histogram)
  
  /* Creates entropy codes for all block types and stores them to the bit
     stream. */
  static void FN(BuildAndStoreEntropyCodes)(MemoryManager* m, BlockEncoder* self,
      const HistogramType* histograms, const size_t histograms_size,
      const size_t alphabet_size, HuffmanTree* tree,
      size_t* storage_ix, uint8_t* storage) {
    const size_t table_size = histograms_size * self->histogram_length_;
    self->depths_ = BROTLI_ALLOC(m, uint8_t, table_size);
    self->bits_ = BROTLI_ALLOC(m, uint16_t, table_size);
    if (BROTLI_IS_OOM(m)) return;
  
    {
      size_t i;
      for (i = 0; i < histograms_size; ++i) {
        size_t ix = i * self->histogram_length_;
        BuildAndStoreHuffmanTree(&histograms[i].data_[0], self->histogram_length_,
            alphabet_size, tree, &self->depths_[ix], &self->bits_[ix],
            storage_ix, storage);
      }
    }
  }
  
  #undef HistogramType
  

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