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73bb3c8530
- Improved compression for triangular meshes (~10%) - Added WebAssembly decoder - Code cleanup + robustness fixes
58 lines
1.8 KiB
C++
58 lines
1.8 KiB
C++
// Copyright 2016 The Draco Authors.
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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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// File provides basic classes and functions for rANS coding.
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#ifndef DRACO_CORE_RANS_BIT_ENCODER_H_
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#define DRACO_CORE_RANS_BIT_ENCODER_H_
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#include <vector>
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#include "core/encoder_buffer.h"
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namespace draco {
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// Class for encoding a sequence of bits using rANS. The probability table used
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// to encode the bits is based off the total counts of bits.
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// TODO(fgalligan): Investigate using an adaptive table for more compression.
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class RAnsBitEncoder {
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public:
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RAnsBitEncoder();
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~RAnsBitEncoder();
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// Must be called before any Encode* function is called.
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void StartEncoding();
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// Encode one bit. If |bit| is true encode a 1, otherwise encode a 0.
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void EncodeBit(bool bit);
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// Encode |nibts| of |value|, starting from the least significant bit.
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// |nbits| must be > 0 and <= 32.
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void EncodeLeastSignificantBits32(int nbits, uint32_t value);
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// Ends the bit encoding and stores the result into the target_buffer.
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void EndEncoding(EncoderBuffer *target_buffer);
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private:
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void Clear();
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std::vector<uint64_t> bit_counts_;
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std::vector<uint32_t> bits_;
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uint32_t local_bits_;
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uint32_t num_local_bits_;
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};
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} // namespace draco
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#endif // DRACO_CORE_RANS_BIT_ENCODER_H_
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