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Diffstat (limited to 'modules/brotli/enc/brotli_bit_stream.h')
-rw-r--r-- | modules/brotli/enc/brotli_bit_stream.h | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/modules/brotli/enc/brotli_bit_stream.h b/modules/brotli/enc/brotli_bit_stream.h new file mode 100644 index 000000000..2ed703bf7 --- /dev/null +++ b/modules/brotli/enc/brotli_bit_stream.h @@ -0,0 +1,84 @@ +/* Copyright 2014 Google Inc. All Rights Reserved. + + Distributed under MIT license. + See file LICENSE for detail or copy at https://opensource.org/licenses/MIT +*/ + +/* Functions to convert brotli-related data structures into the + brotli bit stream. The functions here operate under + assumption that there is enough space in the storage, i.e., there are + no out-of-range checks anywhere. + + These functions do bit addressing into a byte array. The byte array + is called "storage" and the index to the bit is called storage_ix + in function arguments. */ + +#ifndef BROTLI_ENC_BROTLI_BIT_STREAM_H_ +#define BROTLI_ENC_BROTLI_BIT_STREAM_H_ + +#include "../common/context.h" +#include "../common/platform.h" +#include <brotli/types.h> +#include "./command.h" +#include "./entropy_encode.h" +#include "./memory.h" +#include "./metablock.h" + +#if defined(__cplusplus) || defined(c_plusplus) +extern "C" { +#endif + +/* All Store functions here will use a storage_ix, which is always the bit + position for the current storage. */ + +BROTLI_INTERNAL void BrotliStoreHuffmanTree(const uint8_t* depths, size_t num, + HuffmanTree* tree, size_t* storage_ix, uint8_t* storage); + +BROTLI_INTERNAL void BrotliBuildAndStoreHuffmanTreeFast( + MemoryManager* m, const uint32_t* histogram, const size_t histogram_total, + const size_t max_bits, uint8_t* depth, uint16_t* bits, size_t* storage_ix, + uint8_t* storage); + +/* REQUIRES: length > 0 */ +/* REQUIRES: length <= (1 << 24) */ +BROTLI_INTERNAL void BrotliStoreMetaBlock(MemoryManager* m, + const uint8_t* input, size_t start_pos, size_t length, size_t mask, + uint8_t prev_byte, uint8_t prev_byte2, BROTLI_BOOL is_last, + const BrotliEncoderParams* params, ContextType literal_context_mode, + const Command* commands, size_t n_commands, const MetaBlockSplit* mb, + size_t* storage_ix, uint8_t* storage); + +/* Stores the meta-block without doing any block splitting, just collects + one histogram per block category and uses that for entropy coding. + REQUIRES: length > 0 + REQUIRES: length <= (1 << 24) */ +BROTLI_INTERNAL void BrotliStoreMetaBlockTrivial(MemoryManager* m, + const uint8_t* input, size_t start_pos, size_t length, size_t mask, + BROTLI_BOOL is_last, const BrotliEncoderParams* params, + const Command* commands, size_t n_commands, + size_t* storage_ix, uint8_t* storage); + +/* Same as above, but uses static prefix codes for histograms with a only a few + symbols, and uses static code length prefix codes for all other histograms. + REQUIRES: length > 0 + REQUIRES: length <= (1 << 24) */ +BROTLI_INTERNAL void BrotliStoreMetaBlockFast(MemoryManager* m, + const uint8_t* input, size_t start_pos, size_t length, size_t mask, + BROTLI_BOOL is_last, const BrotliEncoderParams* params, + const Command* commands, size_t n_commands, + size_t* storage_ix, uint8_t* storage); + +/* This is for storing uncompressed blocks (simple raw storage of + bytes-as-bytes). + REQUIRES: length > 0 + REQUIRES: length <= (1 << 24) */ +BROTLI_INTERNAL void BrotliStoreUncompressedMetaBlock( + BROTLI_BOOL is_final_block, const uint8_t* BROTLI_RESTRICT input, + size_t position, size_t mask, size_t len, + size_t* BROTLI_RESTRICT storage_ix, uint8_t* BROTLI_RESTRICT storage); + +#if defined(__cplusplus) || defined(c_plusplus) +} /* extern "C" */ +#endif + +#endif /* BROTLI_ENC_BROTLI_BIT_STREAM_H_ */ |