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417107b3dd
The new modes process the input data in independent blocks, using backward references only from within an input block. The new modes can be used by specifying quality 0 or quality 1, the old quality 1 and quality 2 modes are renamed quality 2 and quality 3, respectively, and the old quality 3 mode is removed.
48 lines
2.1 KiB
C++
48 lines
2.1 KiB
C++
/* Copyright 2015 Google Inc. All Rights Reserved.
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Distributed under MIT license.
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See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
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*/
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// Function for fast encoding of an input fragment, independently from the input
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// history. This function uses one-pass processing: when we find a backward
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// match, we immediately emit the corresponding command and literal codes to
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// the bit stream.
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#ifndef BROTLI_ENC_COMPRESS_FRAGMENT_H_
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#define BROTLI_ENC_COMPRESS_FRAGMENT_H_
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#include "./types.h"
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namespace brotli {
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// Compresses "input" string to the "*storage" buffer as one or more complete
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// meta-blocks, and updates the "*storage_ix" bit position.
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//
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// If "is_last" is true, emits an additional empty last meta-block.
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//
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// "cmd_depth" and "cmd_bits" contain the command and distance prefix codes
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// (see comment in encode.h) used for the encoding of this input fragment.
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// If "is_last" is false, they are updated to reflect the statistics
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// of this input fragment, to be used for the encoding of the next fragment.
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//
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// "*cmd_code_numbits" is the number of bits of the compressed representation
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// of the command and distance prefix codes, and "cmd_code" is an array of
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// at least "(*cmd_code_numbits + 7) >> 3" size that contains the compressed
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// command and distance prefix codes. If "is_last" is false, these are also
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// updated to represent the updated "cmd_depth" and "cmd_bits".
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//
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// REQUIRES: "input_size" is greater than zero, or "is_last" is true.
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// REQUIRES: All elements in "table[0..table_size-1]" are initialized to zero.
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// REQUIRES: "table_size" is a power of two
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void BrotliCompressFragmentFast(const uint8_t* input, size_t input_size,
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bool is_last,
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int* table, size_t table_size,
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uint8_t cmd_depth[128], uint16_t cmd_bits[128],
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size_t* cmd_code_numbits, uint8_t* cmd_code,
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size_t* storage_ix, uint8_t* storage);
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} // namespace brotli
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#endif // BROTLI_ENC_COMPRESS_FRAGMENT_H_
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