mirror of
https://github.com/BinomialLLC/basis_universal.git
synced 2026-07-25 23:49:03 +00:00
9529bdbff8
- Adding conditional replenishment (CR) support to the system, so blocks which don't change their selectors or endpoints from the last frame don't need to be decoded. This can greatly increase the compression ratio on many video sequences. - Updating help text. - Adding support for slices to be marked as i-frames - Updating transcoder to support CR
705 lines
16 KiB
C++
705 lines
16 KiB
C++
// basisu_transcoder_internal.h - Universal texture format transcoder library.
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// Copyright (C) 2017-2019 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 basist
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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;
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else
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l = get_bits(basisu::cHuffmanBigRepeatExtraBits) + basisu::cHuffmanBigRepeatSizeMin;
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const uint8_t prev = code_sizes[cur - 1];
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if (prev == 0)
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return false;
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do
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{
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if (cur >= total_used_syms)
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return false;
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code_sizes[cur++] = prev;
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} while (--l > 0);
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}
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}
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if (cur != total_used_syms)
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return false;
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return ct.init(total_used_syms, &code_sizes[0]);
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}
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private:
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uint32_t m_buf_size;
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const uint8_t *m_pBuf;
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const uint8_t *m_pBuf_start;
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const uint8_t *m_pBuf_end;
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uint32_t m_bit_buf;
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uint32_t m_bit_buf_size;
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};
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inline uint32_t basisd_rand(uint32_t seed)
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{
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if (!seed)
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seed++;
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uint32_t z = seed;
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BASISD_znew;
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return z;
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}
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// Returns random number in [0,limit). Max limit is 0xFFFF.
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inline uint32_t basisd_urand(uint32_t& seed, uint32_t limit)
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{
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seed = basisd_rand(seed);
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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 selector
|
|
{
|
|
union
|
|
{
|
|
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);
|
|
}
|
|
}
|
|
}
|
|
|
|
inline uint32_t get_raw_selector(uint32_t x, uint32_t y) const
|
|
{
|
|
assert((x | y) < 4);
|
|
|
|
const uint32_t bit_index = x * 4 + y;
|
|
const uint32_t byte_bit_ofs = bit_index & 7;
|
|
const uint8_t *p = &m_bytes[3 - (bit_index >> 3)];
|
|
const uint32_t lsb = (p[0] >> byte_bit_ofs) & 1;
|
|
const uint32_t msb = (p[-2] >> byte_bit_ofs) & 1;
|
|
const uint32_t val = lsb | (msb << 1);
|
|
|
|
return val;
|
|
}
|
|
|
|
// 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
|
|
{
|
|
static const uint8_t s_etc1_to_selector_index[4] = { 2, 3, 1, 0 };
|
|
return s_etc1_to_selector_index[get_raw_selector(x, y)];
|
|
}
|
|
|
|
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);
|
|
const uint32_t bit_index = x * 4 + y;
|
|
|
|
uint8_t *p = &m_bytes[3 - (bit_index >> 3)];
|
|
|
|
const uint32_t byte_bit_ofs = 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
|
|
|
|
|
|
|