Zoltan Szabadka
cbd5cb55f4
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.
39 lines
1.4 KiB
C++
39 lines
1.4 KiB
C++
// Copyright 2013 Google Inc. All Rights Reserved.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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//
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// Literal cost model to allow backward reference replacement to be efficient.
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#ifndef BROTLI_ENC_LITERAL_COST_H_
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#define BROTLI_ENC_LITERAL_COST_H_
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#include <stddef.h>
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#include <stdint.h>
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namespace brotli {
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// Estimates how many bits the literals in the interval [pos, pos + len) in the
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// ringbuffer (data, mask) will take entropy coded and writes these estimates
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// to the ringbuffer (cost, mask).
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void EstimateBitCostsForLiterals(size_t pos, size_t len, size_t mask,
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const uint8_t *data,
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float *cost);
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void EstimateBitCostsForLiteralsUTF8(size_t pos, size_t len, size_t mask,
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const uint8_t *data,
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float *cost);
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} // namespace brotli
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#endif // BROTLI_ENC_LITERAL_COST_H_
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