mirror of
https://github.com/google/brotli.git
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c6b9c7c5c8
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.
49 lines
1.2 KiB
C
49 lines
1.2 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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// Bit reading helpers
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#include <assert.h>
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#include <stdlib.h>
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#include "./bit_reader.h"
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#if defined(__cplusplus) || defined(c_plusplus)
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extern "C" {
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#endif
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int BrotliInitBitReader(BrotliBitReader* const br, BrotliInput input) {
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size_t i;
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assert(br != NULL);
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br->input_ = input;
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br->val_ = 0;
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br->pos_ = 0;
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br->bit_pos_ = 0;
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br->end_pos_ = 0;
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br->eos_ = 0;
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if (!BrotliReadMoreInput(br)) {
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return 0;
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}
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for (i = 0; i < sizeof(br->val_); ++i) {
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br->val_ |= ((uint64_t)br->buf_[br->pos_]) << (8 * i);
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++br->pos_;
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}
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return (br->end_pos_ > 0);
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}
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#if defined(__cplusplus) || defined(c_plusplus)
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} // extern "C"
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#endif
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