740 lines
17 KiB
C++
740 lines
17 KiB
C++
// basisu_transcoder_internal.h - Universal texture format transcoder library.
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// Copyright (C) 2019 Binomial LLC. All Rights Reserved.
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//
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// Important: If compiling with gcc, be sure strict aliasing is disabled: -fno-strict-aliasing
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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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#pragma once
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#ifdef _MSC_VER
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#pragma warning (disable: 4127) // conditional expression is constant
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#endif
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#define BASISD_LIB_VERSION 107
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#define BASISD_VERSION_STRING "01.11"
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#ifdef _DEBUG
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#define BASISD_BUILD_DEBUG
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#else
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#define BASISD_BUILD_RELEASE
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#endif
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#include "basisu.h"
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#define BASISD_znew (z = 36969 * (z & 65535) + (z >> 16))
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namespace basisu
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{
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extern bool g_debug_printf;
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}
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namespace basist
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{
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// Low-level formats directly supported by the transcoder (other supported texture formats are combinations of these low-level block formats).
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// You probably don't care about these enum's unless you are going pretty low-level and calling the transcoder to decode individual slices.
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enum block_format
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{
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cETC1, // ETC1S RGB
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cBC1, // DXT1 RGB
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cBC4, // DXT5A (alpha block only)
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cPVRTC1_4_RGB, // opaque-only PVRTC1 4bpp
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cPVRTC1_4_RGBA, // PVRTC1 4bpp RGBA
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cBC7_M6_OPAQUE_ONLY, // RGB BC7 mode 6
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cBC7_M5_COLOR, // RGB BC7 mode 5 color (writes an opaque mode 5 block)
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cBC7_M5_ALPHA, // alpha portion of BC7 mode 5 (cBC7_M5_COLOR output data must have been written to the output buffer first to set the mode/rot fields etc.)
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cETC2_EAC_A8, // alpha block of ETC2 EAC (first 8 bytes of the 16-bit ETC2 EAC RGBA format)
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cASTC_4x4, // ASTC 4x4 (either color-only or color+alpha). Note that the transcoder always currently assumes sRGB is not enabled when outputting ASTC
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// data. If you use a sRGB ASTC format you'll get ~1 LSB of additional error, because of the different way ASTC decoders scale 8-bit endpoints to 16-bits during unpacking.
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cATC_RGB,
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cATC_RGBA_INTERPOLATED_ALPHA,
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cIndices, // Used internally: Write 16-bit endpoint and selector indices directly to output (output block must be at least 32-bits)
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cRGB32, // Writes RGB components to 32bpp output pixels
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cRGBA32, // Writes RGB255 components to 32bpp output pixels
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cA32, // Writes alpha component to 32bpp output pixels
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cRGB565,
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cBGR565,
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cRGBA4444_COLOR,
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cRGBA4444_ALPHA,
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cRGBA4444_COLOR_OPAQUE,
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cTotalBlockFormats
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};
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const int COLOR5_PAL0_PREV_HI = 9, COLOR5_PAL0_DELTA_LO = -9, COLOR5_PAL0_DELTA_HI = 31;
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const int COLOR5_PAL1_PREV_HI = 21, COLOR5_PAL1_DELTA_LO = -21, COLOR5_PAL1_DELTA_HI = 21;
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const int COLOR5_PAL2_PREV_HI = 31, COLOR5_PAL2_DELTA_LO = -31, COLOR5_PAL2_DELTA_HI = 9;
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const int COLOR5_PAL_MIN_DELTA_B_RUNLEN = 3, COLOR5_PAL_DELTA_5_RUNLEN_VLC_BITS = 3;
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const uint32_t ENDPOINT_PRED_TOTAL_SYMBOLS = (4 * 4 * 4 * 4) + 1;
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const uint32_t ENDPOINT_PRED_REPEAT_LAST_SYMBOL = ENDPOINT_PRED_TOTAL_SYMBOLS - 1;
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const uint32_t ENDPOINT_PRED_MIN_REPEAT_COUNT = 3;
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const uint32_t ENDPOINT_PRED_COUNT_VLC_BITS = 4;
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const uint32_t NUM_ENDPOINT_PREDS = 3;// BASISU_ARRAY_SIZE(g_endpoint_preds);
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const uint32_t CR_ENDPOINT_PRED_INDEX = NUM_ENDPOINT_PREDS - 1;
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const uint32_t NO_ENDPOINT_PRED_INDEX = 3;//NUM_ENDPOINT_PREDS;
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const uint32_t MAX_SELECTOR_HISTORY_BUF_SIZE = 64;
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const uint32_t SELECTOR_HISTORY_BUF_RLE_COUNT_THRESH = 3;
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const uint32_t SELECTOR_HISTORY_BUF_RLE_COUNT_BITS = 6;
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const uint32_t SELECTOR_HISTORY_BUF_RLE_COUNT_TOTAL = (1 << SELECTOR_HISTORY_BUF_RLE_COUNT_BITS);
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uint16_t crc16(const void *r, size_t size, uint16_t crc);
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class huffman_decoding_table
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{
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friend class bitwise_decoder;
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public:
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huffman_decoding_table()
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{
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}
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void clear()
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{
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basisu::clear_vector(m_code_sizes);
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basisu::clear_vector(m_lookup);
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basisu::clear_vector(m_tree);
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}
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bool init(uint32_t total_syms, const uint8_t *pCode_sizes)
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{
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if (!total_syms)
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{
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clear();
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return true;
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}
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m_code_sizes.resize(total_syms);
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memcpy(&m_code_sizes[0], pCode_sizes, total_syms);
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m_lookup.resize(0);
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m_lookup.resize(basisu::cHuffmanFastLookupSize);
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m_tree.resize(0);
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m_tree.resize(total_syms * 2);
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uint32_t syms_using_codesize[basisu::cHuffmanMaxSupportedInternalCodeSize + 1];
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basisu::clear_obj(syms_using_codesize);
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for (uint32_t i = 0; i < total_syms; i++)
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{
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if (pCode_sizes[i] > basisu::cHuffmanMaxSupportedInternalCodeSize)
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return false;
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syms_using_codesize[pCode_sizes[i]]++;
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}
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uint32_t next_code[basisu::cHuffmanMaxSupportedInternalCodeSize + 1];
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next_code[0] = next_code[1] = 0;
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uint32_t used_syms = 0, total = 0;
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for (uint32_t i = 1; i < basisu::cHuffmanMaxSupportedInternalCodeSize; i++)
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{
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used_syms += syms_using_codesize[i];
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next_code[i + 1] = (total = ((total + syms_using_codesize[i]) << 1));
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}
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if (((1U << basisu::cHuffmanMaxSupportedInternalCodeSize) != total) && (used_syms > 1U))
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return false;
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for (int tree_next = -1, sym_index = 0; sym_index < (int)total_syms; ++sym_index)
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{
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uint32_t rev_code = 0, l, cur_code, code_size = pCode_sizes[sym_index];
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if (!code_size)
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continue;
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cur_code = next_code[code_size]++;
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for (l = code_size; l > 0; l--, cur_code >>= 1)
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rev_code = (rev_code << 1) | (cur_code & 1);
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if (code_size <= basisu::cHuffmanFastLookupBits)
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{
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uint32_t k = (code_size << 16) | sym_index;
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while (rev_code < basisu::cHuffmanFastLookupSize)
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{
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if (m_lookup[rev_code] != 0)
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{
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// Supplied codesizes can't create a valid prefix code.
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return false;
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}
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m_lookup[rev_code] = k;
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rev_code += (1 << code_size);
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}
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continue;
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}
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int tree_cur;
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if (0 == (tree_cur = m_lookup[rev_code & (basisu::cHuffmanFastLookupSize - 1)]))
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{
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const uint32_t idx = rev_code & (basisu::cHuffmanFastLookupSize - 1);
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if (m_lookup[idx] != 0)
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{
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// Supplied codesizes can't create a valid prefix code.
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return false;
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}
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m_lookup[idx] = tree_next;
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tree_cur = tree_next;
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tree_next -= 2;
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}
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if (tree_cur >= 0)
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{
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// Supplied codesizes can't create a valid prefix code.
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return false;
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}
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rev_code >>= (basisu::cHuffmanFastLookupBits - 1);
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for (int j = code_size; j > (basisu::cHuffmanFastLookupBits + 1); j--)
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{
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tree_cur -= ((rev_code >>= 1) & 1);
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const int idx = -tree_cur - 1;
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if (idx < 0)
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return false;
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else if (idx >= (int)m_tree.size())
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m_tree.resize(idx + 1);
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if (!m_tree[idx])
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{
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m_tree[idx] = (int16_t)tree_next;
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tree_cur = tree_next;
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tree_next -= 2;
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}
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else
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{
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tree_cur = m_tree[idx];
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if (tree_cur >= 0)
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{
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// Supplied codesizes can't create a valid prefix code.
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return false;
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}
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}
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}
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tree_cur -= ((rev_code >>= 1) & 1);
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const int idx = -tree_cur - 1;
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if (idx < 0)
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return false;
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else if (idx >= (int)m_tree.size())
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m_tree.resize(idx + 1);
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if (m_tree[idx] != 0)
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{
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// Supplied codesizes can't create a valid prefix code.
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return false;
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}
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m_tree[idx] = (int16_t)sym_index;
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}
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return true;
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}
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const basisu::uint8_vec &get_code_sizes() const { return m_code_sizes; }
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bool is_valid() const { return m_code_sizes.size() > 0; }
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private:
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basisu::uint8_vec m_code_sizes;
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basisu::int_vec m_lookup;
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basisu::int16_vec m_tree;
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};
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class bitwise_decoder
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{
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public:
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bitwise_decoder() :
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m_buf_size(0),
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m_pBuf(nullptr),
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m_pBuf_start(nullptr),
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m_pBuf_end(nullptr),
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m_bit_buf(0),
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m_bit_buf_size(0)
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{
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}
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void clear()
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{
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m_buf_size = 0;
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m_pBuf = nullptr;
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m_pBuf_start = nullptr;
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m_pBuf_end = nullptr;
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m_bit_buf = 0;
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m_bit_buf_size = 0;
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}
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bool init(const uint8_t *pBuf, uint32_t buf_size)
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{
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if ((!pBuf) && (buf_size))
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return false;
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m_buf_size = buf_size;
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m_pBuf = pBuf;
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m_pBuf_start = pBuf;
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m_pBuf_end = pBuf + buf_size;
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m_bit_buf = 0;
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m_bit_buf_size = 0;
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return true;
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}
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void stop()
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{
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}
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inline uint32_t peek_bits(uint32_t num_bits)
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{
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if (!num_bits)
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return 0;
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assert(num_bits <= 25);
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while (m_bit_buf_size < num_bits)
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{
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uint32_t c = 0;
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if (m_pBuf < m_pBuf_end)
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c = *m_pBuf++;
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m_bit_buf |= (c << m_bit_buf_size);
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m_bit_buf_size += 8;
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assert(m_bit_buf_size <= 32);
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}
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return m_bit_buf & ((1 << num_bits) - 1);
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}
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void remove_bits(uint32_t num_bits)
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{
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assert(m_bit_buf_size >= num_bits);
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m_bit_buf >>= num_bits;
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m_bit_buf_size -= num_bits;
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}
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uint32_t get_bits(uint32_t num_bits)
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{
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if (num_bits > 25)
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{
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assert(num_bits <= 32);
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const uint32_t bits0 = peek_bits(25);
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m_bit_buf >>= 25;
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m_bit_buf_size -= 25;
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num_bits -= 25;
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const uint32_t bits = peek_bits(num_bits);
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m_bit_buf >>= num_bits;
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m_bit_buf_size -= num_bits;
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return bits0 | (bits << 25);
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}
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const uint32_t bits = peek_bits(num_bits);
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m_bit_buf >>= num_bits;
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m_bit_buf_size -= num_bits;
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return bits;
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}
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uint32_t decode_truncated_binary(uint32_t n)
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{
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assert(n >= 2);
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const uint32_t k = basisu::floor_log2i(n);
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const uint32_t u = (1 << (k + 1)) - n;
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uint32_t result = get_bits(k);
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if (result >= u)
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result = ((result << 1) | get_bits(1)) - u;
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return result;
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}
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uint32_t decode_rice(uint32_t m)
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{
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assert(m);
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uint32_t q = 0;
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for (;;)
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{
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uint32_t k = peek_bits(16);
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uint32_t l = 0;
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while (k & 1)
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{
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l++;
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k >>= 1;
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}
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q += l;
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remove_bits(l);
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if (l < 16)
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break;
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}
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return (q << m) + (get_bits(m + 1) >> 1);
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}
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inline uint32_t decode_vlc(uint32_t chunk_bits)
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{
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assert(chunk_bits);
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const uint32_t chunk_size = 1 << chunk_bits;
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const uint32_t chunk_mask = chunk_size - 1;
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uint32_t v = 0;
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uint32_t ofs = 0;
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for ( ; ; )
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{
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uint32_t s = get_bits(chunk_bits + 1);
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v |= ((s & chunk_mask) << ofs);
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ofs += chunk_bits;
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if ((s & chunk_size) == 0)
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break;
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if (ofs >= 32)
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{
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assert(0);
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break;
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}
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}
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return v;
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}
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inline uint32_t decode_huffman(const huffman_decoding_table &ct)
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{
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assert(ct.m_code_sizes.size());
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while (m_bit_buf_size < 16)
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{
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uint32_t c = 0;
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if (m_pBuf < m_pBuf_end)
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c = *m_pBuf++;
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m_bit_buf |= (c << m_bit_buf_size);
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m_bit_buf_size += 8;
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assert(m_bit_buf_size <= 32);
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}
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int code_len;
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int sym;
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if ((sym = ct.m_lookup[m_bit_buf & (basisu::cHuffmanFastLookupSize - 1)]) >= 0)
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{
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code_len = sym >> 16;
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sym &= 0xFFFF;
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}
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else
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{
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code_len = basisu::cHuffmanFastLookupBits;
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do
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{
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sym = ct.m_tree[~sym + ((m_bit_buf >> code_len++) & 1)]; // ~sym = -sym - 1
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} while (sym < 0);
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}
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m_bit_buf >>= code_len;
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m_bit_buf_size -= code_len;
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return sym;
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}
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bool read_huffman_table(huffman_decoding_table &ct)
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{
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ct.clear();
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const uint32_t total_used_syms = get_bits(basisu::cHuffmanMaxSymsLog2);
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if (!total_used_syms)
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return true;
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if (total_used_syms > basisu::cHuffmanMaxSyms)
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return false;
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uint8_t code_length_code_sizes[basisu::cHuffmanTotalCodelengthCodes];
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basisu::clear_obj(code_length_code_sizes);
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const uint32_t num_codelength_codes = get_bits(5);
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if ((num_codelength_codes < 1) || (num_codelength_codes > basisu::cHuffmanTotalCodelengthCodes))
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return false;
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for (uint32_t i = 0; i < num_codelength_codes; i++)
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code_length_code_sizes[basisu::g_huffman_sorted_codelength_codes[i]] = static_cast<uint8_t>(get_bits(3));
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huffman_decoding_table code_length_table;
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if (!code_length_table.init(basisu::cHuffmanTotalCodelengthCodes, code_length_code_sizes))
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return false;
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if (!code_length_table.is_valid())
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return false;
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basisu::uint8_vec code_sizes(total_used_syms);
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uint32_t cur = 0;
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while (cur < total_used_syms)
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{
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int c = decode_huffman(code_length_table);
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if (c <= 16)
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code_sizes[cur++] = static_cast<uint8_t>(c);
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else if (c == basisu::cHuffmanSmallZeroRunCode)
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cur += get_bits(basisu::cHuffmanSmallZeroRunExtraBits) + basisu::cHuffmanSmallZeroRunSizeMin;
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else if (c == basisu::cHuffmanBigZeroRunCode)
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cur += get_bits(basisu::cHuffmanBigZeroRunExtraBits) + basisu::cHuffmanBigZeroRunSizeMin;
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else
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{
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if (!cur)
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return false;
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uint32_t l;
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if (c == basisu::cHuffmanSmallRepeatCode)
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l = get_bits(basisu::cHuffmanSmallRepeatExtraBits) + basisu::cHuffmanSmallRepeatSizeMin;
|
|
else
|
|
l = get_bits(basisu::cHuffmanBigRepeatExtraBits) + basisu::cHuffmanBigRepeatSizeMin;
|
|
|
|
const uint8_t prev = code_sizes[cur - 1];
|
|
if (prev == 0)
|
|
return false;
|
|
do
|
|
{
|
|
if (cur >= total_used_syms)
|
|
return false;
|
|
code_sizes[cur++] = prev;
|
|
} while (--l > 0);
|
|
}
|
|
}
|
|
|
|
if (cur != total_used_syms)
|
|
return false;
|
|
|
|
return ct.init(total_used_syms, &code_sizes[0]);
|
|
}
|
|
|
|
private:
|
|
uint32_t m_buf_size;
|
|
const uint8_t *m_pBuf;
|
|
const uint8_t *m_pBuf_start;
|
|
const uint8_t *m_pBuf_end;
|
|
|
|
uint32_t m_bit_buf;
|
|
uint32_t m_bit_buf_size;
|
|
};
|
|
|
|
inline uint32_t basisd_rand(uint32_t seed)
|
|
{
|
|
if (!seed)
|
|
seed++;
|
|
uint32_t z = seed;
|
|
BASISD_znew;
|
|
return z;
|
|
}
|
|
|
|
// Returns random number in [0,limit). Max limit is 0xFFFF.
|
|
inline uint32_t basisd_urand(uint32_t& seed, uint32_t limit)
|
|
{
|
|
seed = basisd_rand(seed);
|
|
return (((seed ^ (seed >> 16)) & 0xFFFF) * limit) >> 16;
|
|
}
|
|
|
|
class approx_move_to_front
|
|
{
|
|
public:
|
|
approx_move_to_front(uint32_t n)
|
|
{
|
|
init(n);
|
|
}
|
|
|
|
void init(uint32_t n)
|
|
{
|
|
m_values.resize(n);
|
|
m_rover = n / 2;
|
|
}
|
|
|
|
const basisu::int_vec& get_values() const { return m_values; }
|
|
basisu::int_vec& get_values() { return m_values; }
|
|
|
|
uint32_t size() const { return (uint32_t)m_values.size(); }
|
|
|
|
const int& operator[] (uint32_t index) const { return m_values[index]; }
|
|
int operator[] (uint32_t index) { return m_values[index]; }
|
|
|
|
void add(int new_value)
|
|
{
|
|
m_values[m_rover++] = new_value;
|
|
if (m_rover == m_values.size())
|
|
m_rover = (uint32_t)m_values.size() / 2;
|
|
}
|
|
|
|
void use(uint32_t index)
|
|
{
|
|
if (index)
|
|
{
|
|
//std::swap(m_values[index / 2], m_values[index]);
|
|
int x = m_values[index / 2];
|
|
int y = m_values[index];
|
|
m_values[index / 2] = y;
|
|
m_values[index] = x;
|
|
}
|
|
}
|
|
|
|
// returns -1 if not found
|
|
int find(int value) const
|
|
{
|
|
for (uint32_t i = 0; i < m_values.size(); i++)
|
|
if (m_values[i] == value)
|
|
return i;
|
|
return -1;
|
|
}
|
|
|
|
void reset()
|
|
{
|
|
const uint32_t n = (uint32_t)m_values.size();
|
|
|
|
m_values.clear();
|
|
|
|
init(n);
|
|
}
|
|
|
|
private:
|
|
basisu::int_vec m_values;
|
|
uint32_t m_rover;
|
|
};
|
|
|
|
struct decoder_etc_block;
|
|
|
|
struct color32
|
|
{
|
|
union
|
|
{
|
|
struct
|
|
{
|
|
uint8_t r;
|
|
uint8_t g;
|
|
uint8_t b;
|
|
uint8_t a;
|
|
};
|
|
|
|
uint8_t c[4];
|
|
|
|
uint32_t m;
|
|
};
|
|
|
|
color32() { }
|
|
|
|
color32(uint32_t vr, uint32_t vg, uint32_t vb, uint32_t va) { set(vr, vg, vb, va); }
|
|
|
|
void set(uint32_t vr, uint32_t vg, uint32_t vb, uint32_t va) { c[0] = static_cast<uint8_t>(vr); c[1] = static_cast<uint8_t>(vg); c[2] = static_cast<uint8_t>(vb); c[3] = static_cast<uint8_t>(va); }
|
|
|
|
uint8_t operator[] (uint32_t idx) const { assert(idx < 4); return c[idx]; }
|
|
uint8_t &operator[] (uint32_t idx) { assert(idx < 4); return c[idx]; }
|
|
|
|
bool operator== (const color32&rhs) const { return m == rhs.m; }
|
|
};
|
|
|
|
struct endpoint
|
|
{
|
|
color32 m_color5;
|
|
uint8_t m_inten5;
|
|
};
|
|
|
|
struct selector
|
|
{
|
|
// Plain selectors (2-bits per value)
|
|
uint8_t m_selectors[4];
|
|
|
|
// ETC1 selectors
|
|
uint8_t m_bytes[4];
|
|
|
|
uint8_t m_lo_selector, m_hi_selector;
|
|
uint8_t m_num_unique_selectors;
|
|
|
|
void init_flags()
|
|
{
|
|
uint32_t hist[4] = { 0, 0, 0, 0 };
|
|
for (uint32_t y = 0; y < 4; y++)
|
|
{
|
|
for (uint32_t x = 0; x < 4; x++)
|
|
{
|
|
uint32_t s = get_selector(x, y);
|
|
hist[s]++;
|
|
}
|
|
}
|
|
|
|
m_lo_selector = 3;
|
|
m_hi_selector = 0;
|
|
m_num_unique_selectors = 0;
|
|
|
|
for (uint32_t i = 0; i < 4; i++)
|
|
{
|
|
if (hist[i])
|
|
{
|
|
m_num_unique_selectors++;
|
|
if (i < m_lo_selector) m_lo_selector = static_cast<uint8_t>(i);
|
|
if (i > m_hi_selector) m_hi_selector = static_cast<uint8_t>(i);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Returned selector value ranges from 0-3 and is a direct index into g_etc1_inten_tables.
|
|
inline uint32_t get_selector(uint32_t x, uint32_t y) const
|
|
{
|
|
assert((x < 4) && (y < 4));
|
|
return (m_selectors[y] >> (x * 2)) & 3;
|
|
}
|
|
|
|
void set_selector(uint32_t x, uint32_t y, uint32_t val)
|
|
{
|
|
static const uint8_t s_selector_index_to_etc1[4] = { 3, 2, 0, 1 };
|
|
|
|
assert((x | y | val) < 4);
|
|
|
|
m_selectors[y] &= ~(3 << (x * 2));
|
|
m_selectors[y] |= (val << (x * 2));
|
|
|
|
const uint32_t etc1_bit_index = x * 4 + y;
|
|
|
|
uint8_t *p = &m_bytes[3 - (etc1_bit_index >> 3)];
|
|
|
|
const uint32_t byte_bit_ofs = etc1_bit_index & 7;
|
|
const uint32_t mask = 1 << byte_bit_ofs;
|
|
|
|
const uint32_t etc1_val = s_selector_index_to_etc1[val];
|
|
|
|
const uint32_t lsb = etc1_val & 1;
|
|
const uint32_t msb = etc1_val >> 1;
|
|
|
|
p[0] &= ~mask;
|
|
p[0] |= (lsb << byte_bit_ofs);
|
|
|
|
p[-2] &= ~mask;
|
|
p[-2] |= (msb << byte_bit_ofs);
|
|
}
|
|
};
|
|
|
|
} // namespace basist
|
|
|
|
|
|
|