37 行
769 B
C++
37 行
769 B
C++
#pragma once
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namespace nall::Decode {
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inline auto Huffman(array_view<u8> input) -> vector<u8> {
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vector<u8> output;
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u32 size = 0;
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for(u32 byte : range(8)) size |= *input++ << byte * 8;
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output.reserve(size);
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u32 byte = 0, bits = 0;
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auto read = [&]() -> bool {
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if(bits == 0) bits = 8, byte = *input++;
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return byte >> --bits & 1;
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};
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u32 nodes[256][2] = {};
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for(u32 offset : range(256)) {
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for(u32 index : range(9)) nodes[offset][0] = nodes[offset][0] << 1 | read();
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for(u32 index : range(9)) nodes[offset][1] = nodes[offset][1] << 1 | read();
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}
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u32 node = 511;
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while(output.size() < size) {
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node = nodes[node - 256][read()];
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if(node < 256) {
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output.append(node);
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node = 511;
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}
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}
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return output;
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}
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}
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