diff options
Diffstat (limited to 'core/fxcodec/codec/ccodec_faxmodule.cpp')
-rw-r--r-- | core/fxcodec/codec/ccodec_faxmodule.cpp | 804 |
1 files changed, 804 insertions, 0 deletions
diff --git a/core/fxcodec/codec/ccodec_faxmodule.cpp b/core/fxcodec/codec/ccodec_faxmodule.cpp new file mode 100644 index 0000000000..af218f7e01 --- /dev/null +++ b/core/fxcodec/codec/ccodec_faxmodule.cpp @@ -0,0 +1,804 @@ +// Copyright 2014 PDFium Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com + +#include "core/fxcodec/codec/ccodec_faxmodule.h" + +#include <algorithm> +#include <memory> +#include <vector> + +#include "core/fxcodec/codec/ccodec_scanlinedecoder.h" +#include "core/fxcodec/codec/codec_int.h" +#include "core/fxcrt/cfx_binarybuf.h" +#include "core/fxcrt/fx_memory.h" +#include "third_party/base/ptr_util.h" +#include "third_party/base/stl_util.h" + +namespace { + +const uint8_t OneLeadPos[256] = { + 8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 3, 3, + 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, + 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, +}; + +// Limit of image dimension. Use the same limit as the JBIG2 codecs. +const int kMaxImageDimension = 65535; + +int FindBit(const uint8_t* data_buf, int max_pos, int start_pos, bool bit) { + ASSERT(start_pos >= 0); + if (start_pos >= max_pos) + return max_pos; + + const uint8_t bit_xor = bit ? 0x00 : 0xff; + int bit_offset = start_pos % 8; + if (bit_offset) { + const int byte_pos = start_pos / 8; + uint8_t data = (data_buf[byte_pos] ^ bit_xor) & (0xff >> bit_offset); + if (data) + return byte_pos * 8 + OneLeadPos[data]; + + start_pos += 7; + } + + const int max_byte = (max_pos + 7) / 8; + int byte_pos = start_pos / 8; + + // Try reading in bigger chunks in case there are long runs to be skipped. + static constexpr int kBulkReadSize = 8; + if (max_byte >= kBulkReadSize && byte_pos < max_byte - kBulkReadSize) { + static constexpr uint8_t skip_block_0[kBulkReadSize] = { + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; + static constexpr uint8_t skip_block_1[kBulkReadSize] = { + 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; + const uint8_t* skip_block = bit ? skip_block_0 : skip_block_1; + while (byte_pos < max_byte - kBulkReadSize && + memcmp(data_buf + byte_pos, skip_block, kBulkReadSize) == 0) { + byte_pos += kBulkReadSize; + } + } + + while (byte_pos < max_byte) { + uint8_t data = data_buf[byte_pos] ^ bit_xor; + if (data) + return std::min(byte_pos * 8 + OneLeadPos[data], max_pos); + + ++byte_pos; + } + return max_pos; +} + +void FaxG4FindB1B2(const std::vector<uint8_t>& ref_buf, + int columns, + int a0, + bool a0color, + int* b1, + int* b2) { + bool first_bit = a0 < 0 || (ref_buf[a0 / 8] & (1 << (7 - a0 % 8))) != 0; + *b1 = FindBit(ref_buf.data(), columns, a0 + 1, !first_bit); + if (*b1 >= columns) { + *b1 = *b2 = columns; + return; + } + if (first_bit == !a0color) { + *b1 = FindBit(ref_buf.data(), columns, *b1 + 1, first_bit); + first_bit = !first_bit; + } + if (*b1 >= columns) { + *b1 = *b2 = columns; + return; + } + *b2 = FindBit(ref_buf.data(), columns, *b1 + 1, first_bit); +} + +void FaxFillBits(uint8_t* dest_buf, int columns, int startpos, int endpos) { + startpos = std::max(startpos, 0); + endpos = pdfium::clamp(endpos, 0, columns); + if (startpos >= endpos) + return; + + int first_byte = startpos / 8; + int last_byte = (endpos - 1) / 8; + if (first_byte == last_byte) { + for (int i = startpos % 8; i <= (endpos - 1) % 8; ++i) + dest_buf[first_byte] -= 1 << (7 - i); + return; + } + + for (int i = startpos % 8; i < 8; ++i) + dest_buf[first_byte] -= 1 << (7 - i); + for (int i = 0; i <= (endpos - 1) % 8; ++i) + dest_buf[last_byte] -= 1 << (7 - i); + + if (last_byte > first_byte + 1) + memset(dest_buf + first_byte + 1, 0, last_byte - first_byte - 1); +} + +inline bool NextBit(const uint8_t* src_buf, int* bitpos) { + int pos = (*bitpos)++; + return !!(src_buf[pos / 8] & (1 << (7 - pos % 8))); +} + +const uint8_t FaxBlackRunIns[] = { + 0, 2, 0x02, 3, 0, 0x03, + 2, 0, 2, 0x02, 1, 0, + 0x03, 4, 0, 2, 0x02, 6, + 0, 0x03, 5, 0, 1, 0x03, + 7, 0, 2, 0x04, 9, 0, + 0x05, 8, 0, 3, 0x04, 10, + 0, 0x05, 11, 0, 0x07, 12, + 0, 2, 0x04, 13, 0, 0x07, + 14, 0, 1, 0x18, 15, 0, + 5, 0x08, 18, 0, 0x0f, 64, + 0, 0x17, 16, 0, 0x18, 17, + 0, 0x37, 0, 0, 10, 0x08, + 0x00, 0x07, 0x0c, 0x40, 0x07, 0x0d, + 0x80, 0x07, 0x17, 24, 0, 0x18, + 25, 0, 0x28, 23, 0, 0x37, + 22, 0, 0x67, 19, 0, 0x68, + 20, 0, 0x6c, 21, 0, 54, + 0x12, 1984 % 256, 1984 / 256, 0x13, 2048 % 256, 2048 / 256, + 0x14, 2112 % 256, 2112 / 256, 0x15, 2176 % 256, 2176 / 256, + 0x16, 2240 % 256, 2240 / 256, 0x17, 2304 % 256, 2304 / 256, + 0x1c, 2368 % 256, 2368 / 256, 0x1d, 2432 % 256, 2432 / 256, + 0x1e, 2496 % 256, 2496 / 256, 0x1f, 2560 % 256, 2560 / 256, + 0x24, 52, 0, 0x27, 55, 0, + 0x28, 56, 0, 0x2b, 59, 0, + 0x2c, 60, 0, 0x33, 320 % 256, 320 / 256, + 0x34, 384 % 256, 384 / 256, 0x35, 448 % 256, 448 / 256, + 0x37, 53, 0, 0x38, 54, 0, + 0x52, 50, 0, 0x53, 51, 0, + 0x54, 44, 0, 0x55, 45, 0, + 0x56, 46, 0, 0x57, 47, 0, + 0x58, 57, 0, 0x59, 58, 0, + 0x5a, 61, 0, 0x5b, 256 % 256, 256 / 256, + 0x64, 48, 0, 0x65, 49, 0, + 0x66, 62, 0, 0x67, 63, 0, + 0x68, 30, 0, 0x69, 31, 0, + 0x6a, 32, 0, 0x6b, 33, 0, + 0x6c, 40, 0, 0x6d, 41, 0, + 0xc8, 128, 0, 0xc9, 192, 0, + 0xca, 26, 0, 0xcb, 27, 0, + 0xcc, 28, 0, 0xcd, 29, 0, + 0xd2, 34, 0, 0xd3, 35, 0, + 0xd4, 36, 0, 0xd5, 37, 0, + 0xd6, 38, 0, 0xd7, 39, 0, + 0xda, 42, 0, 0xdb, 43, 0, + 20, 0x4a, 640 % 256, 640 / 256, 0x4b, 704 % 256, + 704 / 256, 0x4c, 768 % 256, 768 / 256, 0x4d, 832 % 256, + 832 / 256, 0x52, 1280 % 256, 1280 / 256, 0x53, 1344 % 256, + 1344 / 256, 0x54, 1408 % 256, 1408 / 256, 0x55, 1472 % 256, + 1472 / 256, 0x5a, 1536 % 256, 1536 / 256, 0x5b, 1600 % 256, + 1600 / 256, 0x64, 1664 % 256, 1664 / 256, 0x65, 1728 % 256, + 1728 / 256, 0x6c, 512 % 256, 512 / 256, 0x6d, 576 % 256, + 576 / 256, 0x72, 896 % 256, 896 / 256, 0x73, 960 % 256, + 960 / 256, 0x74, 1024 % 256, 1024 / 256, 0x75, 1088 % 256, + 1088 / 256, 0x76, 1152 % 256, 1152 / 256, 0x77, 1216 % 256, + 1216 / 256, 0xff}; + +const uint8_t FaxWhiteRunIns[] = { + 0, 0, 0, 6, 0x07, 2, + 0, 0x08, 3, 0, 0x0B, 4, + 0, 0x0C, 5, 0, 0x0E, 6, + 0, 0x0F, 7, 0, 6, 0x07, + 10, 0, 0x08, 11, 0, 0x12, + 128, 0, 0x13, 8, 0, 0x14, + 9, 0, 0x1b, 64, 0, 9, + 0x03, 13, 0, 0x07, 1, 0, + 0x08, 12, 0, 0x17, 192, 0, + 0x18, 1664 % 256, 1664 / 256, 0x2a, 16, 0, + 0x2B, 17, 0, 0x34, 14, 0, + 0x35, 15, 0, 12, 0x03, 22, + 0, 0x04, 23, 0, 0x08, 20, + 0, 0x0c, 19, 0, 0x13, 26, + 0, 0x17, 21, 0, 0x18, 28, + 0, 0x24, 27, 0, 0x27, 18, + 0, 0x28, 24, 0, 0x2B, 25, + 0, 0x37, 256 % 256, 256 / 256, 42, 0x02, + 29, 0, 0x03, 30, 0, 0x04, + 45, 0, 0x05, 46, 0, 0x0a, + 47, 0, 0x0b, 48, 0, 0x12, + 33, 0, 0x13, 34, 0, 0x14, + 35, 0, 0x15, 36, 0, 0x16, + 37, 0, 0x17, 38, 0, 0x1a, + 31, 0, 0x1b, 32, 0, 0x24, + 53, 0, 0x25, 54, 0, 0x28, + 39, 0, 0x29, 40, 0, 0x2a, + 41, 0, 0x2b, 42, 0, 0x2c, + 43, 0, 0x2d, 44, 0, 0x32, + 61, 0, 0x33, 62, 0, 0x34, + 63, 0, 0x35, 0, 0, 0x36, + 320 % 256, 320 / 256, 0x37, 384 % 256, 384 / 256, 0x4a, + 59, 0, 0x4b, 60, 0, 0x52, + 49, 0, 0x53, 50, 0, 0x54, + 51, 0, 0x55, 52, 0, 0x58, + 55, 0, 0x59, 56, 0, 0x5a, + 57, 0, 0x5b, 58, 0, 0x64, + 448 % 256, 448 / 256, 0x65, 512 % 256, 512 / 256, 0x67, + 640 % 256, 640 / 256, 0x68, 576 % 256, 576 / 256, 16, + 0x98, 1472 % 256, 1472 / 256, 0x99, 1536 % 256, 1536 / 256, + 0x9a, 1600 % 256, 1600 / 256, 0x9b, 1728 % 256, 1728 / 256, + 0xcc, 704 % 256, 704 / 256, 0xcd, 768 % 256, 768 / 256, + 0xd2, 832 % 256, 832 / 256, 0xd3, 896 % 256, 896 / 256, + 0xd4, 960 % 256, 960 / 256, 0xd5, 1024 % 256, 1024 / 256, + 0xd6, 1088 % 256, 1088 / 256, 0xd7, 1152 % 256, 1152 / 256, + 0xd8, 1216 % 256, 1216 / 256, 0xd9, 1280 % 256, 1280 / 256, + 0xda, 1344 % 256, 1344 / 256, 0xdb, 1408 % 256, 1408 / 256, + 0, 3, 0x08, 1792 % 256, 1792 / 256, 0x0c, + 1856 % 256, 1856 / 256, 0x0d, 1920 % 256, 1920 / 256, 10, + 0x12, 1984 % 256, 1984 / 256, 0x13, 2048 % 256, 2048 / 256, + 0x14, 2112 % 256, 2112 / 256, 0x15, 2176 % 256, 2176 / 256, + 0x16, 2240 % 256, 2240 / 256, 0x17, 2304 % 256, 2304 / 256, + 0x1c, 2368 % 256, 2368 / 256, 0x1d, 2432 % 256, 2432 / 256, + 0x1e, 2496 % 256, 2496 / 256, 0x1f, 2560 % 256, 2560 / 256, + 0xff, +}; + +int FaxGetRun(const uint8_t* ins_array, + const uint8_t* src_buf, + int* bitpos, + int bitsize) { + uint32_t code = 0; + int ins_off = 0; + while (1) { + uint8_t ins = ins_array[ins_off++]; + if (ins == 0xff) + return -1; + + if (*bitpos >= bitsize) + return -1; + + code <<= 1; + if (src_buf[*bitpos / 8] & (1 << (7 - *bitpos % 8))) + ++code; + + ++(*bitpos); + int next_off = ins_off + ins * 3; + for (; ins_off < next_off; ins_off += 3) { + if (ins_array[ins_off] == code) + return ins_array[ins_off + 1] + ins_array[ins_off + 2] * 256; + } + } +} + +void FaxG4GetRow(const uint8_t* src_buf, + int bitsize, + int* bitpos, + uint8_t* dest_buf, + const std::vector<uint8_t>& ref_buf, + int columns) { + int a0 = -1; + bool a0color = true; + while (1) { + if (*bitpos >= bitsize) + return; + + int a1; + int a2; + int b1; + int b2; + FaxG4FindB1B2(ref_buf, columns, a0, a0color, &b1, &b2); + + int v_delta = 0; + if (!NextBit(src_buf, bitpos)) { + if (*bitpos >= bitsize) + return; + + bool bit1 = NextBit(src_buf, bitpos); + if (*bitpos >= bitsize) + return; + + bool bit2 = NextBit(src_buf, bitpos); + if (bit1) { + v_delta = bit2 ? 1 : -1; + } else if (bit2) { + int run_len1 = 0; + while (1) { + int run = FaxGetRun(a0color ? FaxWhiteRunIns : FaxBlackRunIns, + src_buf, bitpos, bitsize); + run_len1 += run; + if (run < 64) + break; + } + if (a0 < 0) + ++run_len1; + if (run_len1 < 0) + return; + + a1 = a0 + run_len1; + if (!a0color) + FaxFillBits(dest_buf, columns, a0, a1); + + int run_len2 = 0; + while (1) { + int run = FaxGetRun(a0color ? FaxBlackRunIns : FaxWhiteRunIns, + src_buf, bitpos, bitsize); + run_len2 += run; + if (run < 64) + break; + } + if (run_len2 < 0) + return; + a2 = a1 + run_len2; + if (a0color) + FaxFillBits(dest_buf, columns, a1, a2); + + a0 = a2; + if (a0 < columns) + continue; + + return; + } else { + if (*bitpos >= bitsize) + return; + + if (NextBit(src_buf, bitpos)) { + if (!a0color) + FaxFillBits(dest_buf, columns, a0, b2); + + if (b2 >= columns) + return; + + a0 = b2; + continue; + } + + if (*bitpos >= bitsize) + return; + + bool next_bit1 = NextBit(src_buf, bitpos); + if (*bitpos >= bitsize) + return; + + bool next_bit2 = NextBit(src_buf, bitpos); + if (next_bit1) { + v_delta = next_bit2 ? 2 : -2; + } else if (next_bit2) { + if (*bitpos >= bitsize) + return; + + v_delta = NextBit(src_buf, bitpos) ? 3 : -3; + } else { + if (*bitpos >= bitsize) + return; + + if (NextBit(src_buf, bitpos)) { + *bitpos += 3; + continue; + } + *bitpos += 5; + return; + } + } + } + a1 = b1 + v_delta; + if (!a0color) + FaxFillBits(dest_buf, columns, a0, a1); + + if (a1 >= columns) + return; + + // The position of picture element must be monotonic increasing. + if (a0 >= a1) + return; + + a0 = a1; + a0color = !a0color; + } +} + +void FaxSkipEOL(const uint8_t* src_buf, int bitsize, int* bitpos) { + int startbit = *bitpos; + while (*bitpos < bitsize) { + if (!NextBit(src_buf, bitpos)) + continue; + if (*bitpos - startbit <= 11) + *bitpos = startbit; + return; + } +} + +void FaxGet1DLine(const uint8_t* src_buf, + int bitsize, + int* bitpos, + std::vector<uint8_t>* dest_buf, + int columns) { + bool color = true; + int startpos = 0; + while (1) { + if (*bitpos >= bitsize) + return; + + int run_len = 0; + while (1) { + int run = FaxGetRun(color ? FaxWhiteRunIns : FaxBlackRunIns, src_buf, + bitpos, bitsize); + if (run < 0) { + while (*bitpos < bitsize) { + if (NextBit(src_buf, bitpos)) + return; + } + return; + } + run_len += run; + if (run < 64) + break; + } + if (!color) + FaxFillBits(dest_buf->data(), columns, startpos, startpos + run_len); + + startpos += run_len; + if (startpos >= columns) + break; + + color = !color; + } +} + +} // namespace + +class CCodec_FaxDecoder final : public CCodec_ScanlineDecoder { + public: + CCodec_FaxDecoder(const uint8_t* src_buf, + uint32_t src_size, + int width, + int height, + uint32_t pitch, + int K, + bool EndOfLine, + bool EncodedByteAlign, + bool BlackIs1); + ~CCodec_FaxDecoder() override; + + // CCodec_ScanlineDecoder + bool v_Rewind() override; + uint8_t* v_GetNextLine() override; + uint32_t GetSrcOffset() override; + + private: + const int m_Encoding; + int m_bitpos; + bool m_bByteAlign; + const bool m_bEndOfLine; + const bool m_bBlack; + const uint32_t m_SrcSize; + const uint8_t* const m_pSrcBuf; + std::vector<uint8_t> m_ScanlineBuf; + std::vector<uint8_t> m_RefBuf; +}; + +CCodec_FaxDecoder::CCodec_FaxDecoder(const uint8_t* src_buf, + uint32_t src_size, + int width, + int height, + uint32_t pitch, + int K, + bool EndOfLine, + bool EncodedByteAlign, + bool BlackIs1) + : CCodec_ScanlineDecoder(width, height, width, height, 1, 1, pitch), + m_Encoding(K), + m_bitpos(0), + m_bByteAlign(EncodedByteAlign), + m_bEndOfLine(EndOfLine), + m_bBlack(BlackIs1), + m_SrcSize(src_size), + m_pSrcBuf(src_buf), + m_ScanlineBuf(pitch), + m_RefBuf(pitch) {} + +CCodec_FaxDecoder::~CCodec_FaxDecoder() {} + +bool CCodec_FaxDecoder::v_Rewind() { + memset(m_RefBuf.data(), 0xff, m_RefBuf.size()); + m_bitpos = 0; + return true; +} + +uint8_t* CCodec_FaxDecoder::v_GetNextLine() { + int bitsize = m_SrcSize * 8; + FaxSkipEOL(m_pSrcBuf, bitsize, &m_bitpos); + if (m_bitpos >= bitsize) + return nullptr; + + memset(m_ScanlineBuf.data(), 0xff, m_ScanlineBuf.size()); + if (m_Encoding < 0) { + FaxG4GetRow(m_pSrcBuf, bitsize, &m_bitpos, m_ScanlineBuf.data(), m_RefBuf, + m_OrigWidth); + m_RefBuf = m_ScanlineBuf; + } else if (m_Encoding == 0) { + FaxGet1DLine(m_pSrcBuf, bitsize, &m_bitpos, &m_ScanlineBuf, m_OrigWidth); + } else { + if (NextBit(m_pSrcBuf, &m_bitpos)) { + FaxGet1DLine(m_pSrcBuf, bitsize, &m_bitpos, &m_ScanlineBuf, m_OrigWidth); + } else { + FaxG4GetRow(m_pSrcBuf, bitsize, &m_bitpos, m_ScanlineBuf.data(), m_RefBuf, + m_OrigWidth); + } + m_RefBuf = m_ScanlineBuf; + } + if (m_bEndOfLine) + FaxSkipEOL(m_pSrcBuf, bitsize, &m_bitpos); + + if (m_bByteAlign && m_bitpos < bitsize) { + int bitpos0 = m_bitpos; + int bitpos1 = (m_bitpos + 7) / 8 * 8; + while (m_bByteAlign && bitpos0 < bitpos1) { + int bit = m_pSrcBuf[bitpos0 / 8] & (1 << (7 - bitpos0 % 8)); + if (bit != 0) + m_bByteAlign = false; + else + ++bitpos0; + } + if (m_bByteAlign) + m_bitpos = bitpos1; + } + if (m_bBlack) { + ASSERT(m_Pitch == m_ScanlineBuf.size()); + ASSERT(m_Pitch % 4 == 0); + uint32_t* data = reinterpret_cast<uint32_t*>(m_ScanlineBuf.data()); + for (size_t i = 0; i < m_ScanlineBuf.size() / 4; ++i) + data[i] = ~data[i]; + } + return m_ScanlineBuf.data(); +} + +uint32_t CCodec_FaxDecoder::GetSrcOffset() { + return std::min(static_cast<uint32_t>((m_bitpos + 7) / 8), m_SrcSize); +} + +void FaxG4Decode(const uint8_t* src_buf, + uint32_t src_size, + int* pbitpos, + uint8_t* dest_buf, + int width, + int height, + int pitch) { + if (pitch == 0) + pitch = (width + 7) / 8; + + std::vector<uint8_t> ref_buf(pitch, 0xff); + int bitpos = *pbitpos; + for (int iRow = 0; iRow < height; iRow++) { + uint8_t* line_buf = dest_buf + iRow * pitch; + memset(line_buf, 0xff, pitch); + FaxG4GetRow(src_buf, src_size << 3, &bitpos, line_buf, ref_buf, width); + memcpy(ref_buf.data(), line_buf, pitch); + } + *pbitpos = bitpos; +} + +std::unique_ptr<CCodec_ScanlineDecoder> CCodec_FaxModule::CreateDecoder( + const uint8_t* src_buf, + uint32_t src_size, + int width, + int height, + int K, + bool EndOfLine, + bool EncodedByteAlign, + bool BlackIs1, + int Columns, + int Rows) { + int actual_width = Columns ? Columns : width; + int actual_height = Rows ? Rows : height; + + // Reject invalid values. + if (actual_width <= 0 || actual_height <= 0) + return nullptr; + + // Reject unreasonable large input. + if (actual_width > kMaxImageDimension || actual_height > kMaxImageDimension) + return nullptr; + + uint32_t pitch = (static_cast<uint32_t>(actual_width) + 31) / 32 * 4; + return pdfium::MakeUnique<CCodec_FaxDecoder>( + src_buf, src_size, actual_width, actual_height, pitch, K, EndOfLine, + EncodedByteAlign, BlackIs1); +} + +#if _FX_PLATFORM_ == _FX_PLATFORM_WINDOWS_ +namespace { +const uint8_t BlackRunTerminator[128] = { + 0x37, 10, 0x02, 3, 0x03, 2, 0x02, 2, 0x03, 3, 0x03, 4, 0x02, 4, + 0x03, 5, 0x05, 6, 0x04, 6, 0x04, 7, 0x05, 7, 0x07, 7, 0x04, 8, + 0x07, 8, 0x18, 9, 0x17, 10, 0x18, 10, 0x08, 10, 0x67, 11, 0x68, 11, + 0x6c, 11, 0x37, 11, 0x28, 11, 0x17, 11, 0x18, 11, 0xca, 12, 0xcb, 12, + 0xcc, 12, 0xcd, 12, 0x68, 12, 0x69, 12, 0x6a, 12, 0x6b, 12, 0xd2, 12, + 0xd3, 12, 0xd4, 12, 0xd5, 12, 0xd6, 12, 0xd7, 12, 0x6c, 12, 0x6d, 12, + 0xda, 12, 0xdb, 12, 0x54, 12, 0x55, 12, 0x56, 12, 0x57, 12, 0x64, 12, + 0x65, 12, 0x52, 12, 0x53, 12, 0x24, 12, 0x37, 12, 0x38, 12, 0x27, 12, + 0x28, 12, 0x58, 12, 0x59, 12, 0x2b, 12, 0x2c, 12, 0x5a, 12, 0x66, 12, + 0x67, 12, +}; + +const uint8_t BlackRunMarkup[80] = { + 0x0f, 10, 0xc8, 12, 0xc9, 12, 0x5b, 12, 0x33, 12, 0x34, 12, 0x35, 12, + 0x6c, 13, 0x6d, 13, 0x4a, 13, 0x4b, 13, 0x4c, 13, 0x4d, 13, 0x72, 13, + 0x73, 13, 0x74, 13, 0x75, 13, 0x76, 13, 0x77, 13, 0x52, 13, 0x53, 13, + 0x54, 13, 0x55, 13, 0x5a, 13, 0x5b, 13, 0x64, 13, 0x65, 13, 0x08, 11, + 0x0c, 11, 0x0d, 11, 0x12, 12, 0x13, 12, 0x14, 12, 0x15, 12, 0x16, 12, + 0x17, 12, 0x1c, 12, 0x1d, 12, 0x1e, 12, 0x1f, 12, +}; + +const uint8_t WhiteRunTerminator[128] = { + 0x35, 8, 0x07, 6, 0x07, 4, 0x08, 4, 0x0B, 4, 0x0C, 4, 0x0E, 4, 0x0F, 4, + 0x13, 5, 0x14, 5, 0x07, 5, 0x08, 5, 0x08, 6, 0x03, 6, 0x34, 6, 0x35, 6, + 0x2a, 6, 0x2B, 6, 0x27, 7, 0x0c, 7, 0x08, 7, 0x17, 7, 0x03, 7, 0x04, 7, + 0x28, 7, 0x2B, 7, 0x13, 7, 0x24, 7, 0x18, 7, 0x02, 8, 0x03, 8, 0x1a, 8, + 0x1b, 8, 0x12, 8, 0x13, 8, 0x14, 8, 0x15, 8, 0x16, 8, 0x17, 8, 0x28, 8, + 0x29, 8, 0x2a, 8, 0x2b, 8, 0x2c, 8, 0x2d, 8, 0x04, 8, 0x05, 8, 0x0a, 8, + 0x0b, 8, 0x52, 8, 0x53, 8, 0x54, 8, 0x55, 8, 0x24, 8, 0x25, 8, 0x58, 8, + 0x59, 8, 0x5a, 8, 0x5b, 8, 0x4a, 8, 0x4b, 8, 0x32, 8, 0x33, 8, 0x34, 8, +}; + +const uint8_t WhiteRunMarkup[80] = { + 0x1b, 5, 0x12, 5, 0x17, 6, 0x37, 7, 0x36, 8, 0x37, 8, 0x64, 8, + 0x65, 8, 0x68, 8, 0x67, 8, 0xcc, 9, 0xcd, 9, 0xd2, 9, 0xd3, 9, + 0xd4, 9, 0xd5, 9, 0xd6, 9, 0xd7, 9, 0xd8, 9, 0xd9, 9, 0xda, 9, + 0xdb, 9, 0x98, 9, 0x99, 9, 0x9a, 9, 0x18, 6, 0x9b, 9, 0x08, 11, + 0x0c, 11, 0x0d, 11, 0x12, 12, 0x13, 12, 0x14, 12, 0x15, 12, 0x16, 12, + 0x17, 12, 0x1c, 12, 0x1d, 12, 0x1e, 12, 0x1f, 12, +}; + +void AddBitStream(uint8_t* dest_buf, int* dest_bitpos, int data, int bitlen) { + for (int i = bitlen - 1; i >= 0; i--) { + if (data & (1 << i)) + dest_buf[*dest_bitpos / 8] |= 1 << (7 - *dest_bitpos % 8); + (*dest_bitpos)++; + } +} + +void FaxEncodeRun(uint8_t* dest_buf, int* dest_bitpos, int run, bool bWhite) { + while (run >= 2560) { + AddBitStream(dest_buf, dest_bitpos, 0x1f, 12); + run -= 2560; + } + if (run >= 64) { + int markup = run - run % 64; + const uint8_t* p = bWhite ? WhiteRunMarkup : BlackRunMarkup; + p += (markup / 64 - 1) * 2; + AddBitStream(dest_buf, dest_bitpos, *p, p[1]); + } + run %= 64; + const uint8_t* p = bWhite ? WhiteRunTerminator : BlackRunTerminator; + p += run * 2; + AddBitStream(dest_buf, dest_bitpos, *p, p[1]); +} + +void FaxEncode2DLine(uint8_t* dest_buf, + int* dest_bitpos, + const uint8_t* src_buf, + const std::vector<uint8_t>& ref_buf, + int cols) { + int a0 = -1; + bool a0color = true; + while (1) { + int a1 = FindBit(src_buf, cols, a0 + 1, !a0color); + int b1; + int b2; + FaxG4FindB1B2(ref_buf, cols, a0, a0color, &b1, &b2); + if (b2 < a1) { + *dest_bitpos += 3; + dest_buf[*dest_bitpos / 8] |= 1 << (7 - *dest_bitpos % 8); + (*dest_bitpos)++; + a0 = b2; + } else if (a1 - b1 <= 3 && b1 - a1 <= 3) { + int delta = a1 - b1; + switch (delta) { + case 0: + dest_buf[*dest_bitpos / 8] |= 1 << (7 - *dest_bitpos % 8); + break; + case 1: + case 2: + case 3: + *dest_bitpos += delta == 1 ? 1 : delta + 2; + dest_buf[*dest_bitpos / 8] |= 1 << (7 - *dest_bitpos % 8); + (*dest_bitpos)++; + dest_buf[*dest_bitpos / 8] |= 1 << (7 - *dest_bitpos % 8); + break; + case -1: + case -2: + case -3: + *dest_bitpos += delta == -1 ? 1 : -delta + 2; + dest_buf[*dest_bitpos / 8] |= 1 << (7 - *dest_bitpos % 8); + (*dest_bitpos)++; + break; + } + (*dest_bitpos)++; + a0 = a1; + a0color = !a0color; + } else { + int a2 = FindBit(src_buf, cols, a1 + 1, a0color); + (*dest_bitpos)++; + (*dest_bitpos)++; + dest_buf[*dest_bitpos / 8] |= 1 << (7 - *dest_bitpos % 8); + (*dest_bitpos)++; + if (a0 < 0) + a0 = 0; + FaxEncodeRun(dest_buf, dest_bitpos, a1 - a0, a0color); + FaxEncodeRun(dest_buf, dest_bitpos, a2 - a1, !a0color); + a0 = a2; + } + if (a0 >= cols) + return; + } +} + +class CCodec_FaxEncoder { + public: + CCodec_FaxEncoder(const uint8_t* src_buf, int width, int height, int pitch); + ~CCodec_FaxEncoder(); + void Encode(std::unique_ptr<uint8_t, FxFreeDeleter>* dest_buf, + uint32_t* dest_size); + + private: + CFX_BinaryBuf m_DestBuf; + std::vector<uint8_t> m_RefLine; + uint8_t* m_pLineBuf; + const int m_Cols; + const int m_Rows; + const int m_Pitch; + const uint8_t* m_pSrcBuf; +}; + +CCodec_FaxEncoder::CCodec_FaxEncoder(const uint8_t* src_buf, + int width, + int height, + int pitch) + : m_Cols(width), m_Rows(height), m_Pitch(pitch), m_pSrcBuf(src_buf) { + m_RefLine.resize(m_Pitch); + memset(m_RefLine.data(), 0xff, m_Pitch); + m_pLineBuf = FX_Alloc2D(uint8_t, m_Pitch, 8); + m_DestBuf.SetAllocStep(10240); +} + +CCodec_FaxEncoder::~CCodec_FaxEncoder() { + FX_Free(m_pLineBuf); +} + +void CCodec_FaxEncoder::Encode( + std::unique_ptr<uint8_t, FxFreeDeleter>* dest_buf, + uint32_t* dest_size) { + int dest_bitpos = 0; + uint8_t last_byte = 0; + for (int i = 0; i < m_Rows; i++) { + const uint8_t* scan_line = m_pSrcBuf + i * m_Pitch; + memset(m_pLineBuf, 0, m_Pitch * 8); + m_pLineBuf[0] = last_byte; + FaxEncode2DLine(m_pLineBuf, &dest_bitpos, scan_line, m_RefLine, m_Cols); + m_DestBuf.AppendBlock(m_pLineBuf, dest_bitpos / 8); + last_byte = m_pLineBuf[dest_bitpos / 8]; + dest_bitpos %= 8; + memcpy(m_RefLine.data(), scan_line, m_Pitch); + } + if (dest_bitpos) + m_DestBuf.AppendByte(last_byte); + *dest_size = m_DestBuf.GetSize(); + *dest_buf = m_DestBuf.DetachBuffer(); +} + +} // namespace + +void CCodec_FaxModule::FaxEncode( + const uint8_t* src_buf, + int width, + int height, + int pitch, + std::unique_ptr<uint8_t, FxFreeDeleter>* dest_buf, + uint32_t* dest_size) { + CCodec_FaxEncoder encoder(src_buf, width, height, pitch); + encoder.Encode(dest_buf, dest_size); +} + +#endif // _FX_PLATFORM_ == _FX_PLATFORM_WINDOWS_ |