clang-format all pdfium code.

core/src/fxcodec/codec/fx_codec_flate.cpp

 // 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 "../../../../third_party/base/nonstd_unique_ptr.h"
 #include "../../../../third_party/zlib_v128/zlib.h"
 #include "../../../include/fxcodec/fx_codec.h"
 #include "../../../include/fxcodec/fx_codec_flate.h"
 #include "codec_int.h"
 
-extern "C"
-{
-    static void* my_alloc_func(void* opaque, unsigned int items, unsigned int size)
-    {
-        return FX_Alloc2D(uint8_t, items, size);
-    }
-    static void my_free_func(void* opaque, void* address)
-    {
-        FX_Free(address);
-    }
-    static int FPDFAPI_FlateGetTotalOut(void* context)
-    {
-        return ((z_stream*)context)->total_out;
-    }
-    static int FPDFAPI_FlateGetTotalIn(void* context)
-    {
-        return ((z_stream*)context)->total_in;
-    }
-    static void FPDFAPI_FlateCompress(unsigned char* dest_buf,
-                                      unsigned long* dest_size,
-                                      const unsigned char* src_buf,
-                                      unsigned long src_size)
-    {
-        compress(dest_buf, dest_size, src_buf, src_size);
-    }
-    void* FPDFAPI_FlateInit(void* (*alloc_func)(void*, unsigned int, unsigned int),
-                            void (*free_func)(void*, void*))
-    {
-        z_stream* p = (z_stream*)alloc_func(0, 1, sizeof(z_stream));
-        if (p == NULL) {
-            return NULL;
-        }
-        FXSYS_memset(p, 0, sizeof(z_stream));
-        p->zalloc = alloc_func;
-        p->zfree = free_func;
-        inflateInit(p);
-        return p;
-    }
-    void FPDFAPI_FlateInput(void* context, const unsigned char* src_buf, unsigned int src_size)
-    {
-        ((z_stream*)context)->next_in = (unsigned char*)src_buf;
-        ((z_stream*)context)->avail_in = src_size;
-    }
-    int FPDFAPI_FlateOutput(void* context, unsigned char* dest_buf, unsigned int dest_size)
-    {
-        ((z_stream*)context)->next_out = dest_buf;
-        ((z_stream*)context)->avail_out = dest_size;
-        unsigned int pre_pos = (unsigned int)FPDFAPI_FlateGetTotalOut(context);
-        int ret = inflate((z_stream*)context, Z_SYNC_FLUSH);
-        unsigned int post_pos = (unsigned int)FPDFAPI_FlateGetTotalOut(context);
-        unsigned int written = post_pos - pre_pos;
-        if (written < dest_size) {
-            FXSYS_memset(dest_buf + written, '\0', dest_size - written);
-        }
-        return ret;
-    }
-    int FPDFAPI_FlateGetAvailIn(void* context)
-    {
-        return ((z_stream*)context)->avail_in;
-    }
-    int FPDFAPI_FlateGetAvailOut(void* context)
-    {
-        return ((z_stream*)context)->avail_out;
-    }
-    void FPDFAPI_FlateEnd(void* context)
-    {
-        inflateEnd((z_stream*)context);
-        ((z_stream*)context)->zfree(0, context);
-    }
+extern "C" {
+static void* my_alloc_func(void* opaque,
+                           unsigned int items,
+                           unsigned int size) {
+  return FX_Alloc2D(uint8_t, items, size);
+}
+static void my_free_func(void* opaque, void* address) {
+  FX_Free(address);
+}
+static int FPDFAPI_FlateGetTotalOut(void* context) {
+  return ((z_stream*)context)->total_out;
+}
+static int FPDFAPI_FlateGetTotalIn(void* context) {
+  return ((z_stream*)context)->total_in;
+}
+static void FPDFAPI_FlateCompress(unsigned char* dest_buf,
+                                  unsigned long* dest_size,
+                                  const unsigned char* src_buf,
+                                  unsigned long src_size) {
+  compress(dest_buf, dest_size, src_buf, src_size);
+}
+void* FPDFAPI_FlateInit(void* (*alloc_func)(void*, unsigned int, unsigned int),
+                        void (*free_func)(void*, void*)) {
+  z_stream* p = (z_stream*)alloc_func(0, 1, sizeof(z_stream));
+  if (p == NULL) {
+    return NULL;
+  }
+  FXSYS_memset(p, 0, sizeof(z_stream));
+  p->zalloc = alloc_func;
+  p->zfree = free_func;
+  inflateInit(p);
+  return p;
+}
+void FPDFAPI_FlateInput(void* context,
+                        const unsigned char* src_buf,
+                        unsigned int src_size) {
+  ((z_stream*)context)->next_in = (unsigned char*)src_buf;
+  ((z_stream*)context)->avail_in = src_size;
+}
+int FPDFAPI_FlateOutput(void* context,
+                        unsigned char* dest_buf,
+                        unsigned int dest_size) {
+  ((z_stream*)context)->next_out = dest_buf;
+  ((z_stream*)context)->avail_out = dest_size;
+  unsigned int pre_pos = (unsigned int)FPDFAPI_FlateGetTotalOut(context);
+  int ret = inflate((z_stream*)context, Z_SYNC_FLUSH);
+  unsigned int post_pos = (unsigned int)FPDFAPI_FlateGetTotalOut(context);
+  unsigned int written = post_pos - pre_pos;
+  if (written < dest_size) {
+    FXSYS_memset(dest_buf + written, '\0', dest_size - written);
+  }
+  return ret;
+}
+int FPDFAPI_FlateGetAvailIn(void* context) {
+  return ((z_stream*)context)->avail_in;
+}
+int FPDFAPI_FlateGetAvailOut(void* context) {
+  return ((z_stream*)context)->avail_out;
+}
+void FPDFAPI_FlateEnd(void* context) {
+  inflateEnd((z_stream*)context);
+  ((z_stream*)context)->zfree(0, context);
+}
 }  // extern "C"
 
-class CLZWDecoder
-{
-public:
-    int Decode(uint8_t* output, FX_DWORD& outlen, const uint8_t* input, FX_DWORD& size, FX_BOOL bEarlyChange);
+class CLZWDecoder {
+ public:
+  int Decode(uint8_t* output,
+             FX_DWORD& outlen,
+             const uint8_t* input,
+             FX_DWORD& size,
+             FX_BOOL bEarlyChange);
 
-private:
-    void AddCode(FX_DWORD prefix_code, uint8_t append_char);
-    void DecodeString(FX_DWORD code);
+ private:
+  void AddCode(FX_DWORD prefix_code, uint8_t append_char);
+  void DecodeString(FX_DWORD code);
 
-    FX_DWORD    m_InPos;
-    FX_DWORD    m_OutPos;
-    uint8_t*    m_pOutput;
-    const uint8_t*      m_pInput;
-    FX_BOOL             m_Early;
-    FX_DWORD    m_CodeArray[5021];
-    FX_DWORD    m_nCodes;
-    uint8_t             m_DecodeStack[4000];
-    FX_DWORD    m_StackLen;
-    int                 m_CodeLen;
+  FX_DWORD m_InPos;
+  FX_DWORD m_OutPos;
+  uint8_t* m_pOutput;
+  const uint8_t* m_pInput;
+  FX_BOOL m_Early;
+  FX_DWORD m_CodeArray[5021];
+  FX_DWORD m_nCodes;
+  uint8_t m_DecodeStack[4000];
+  FX_DWORD m_StackLen;
+  int m_CodeLen;
 };
-void CLZWDecoder::AddCode(FX_DWORD prefix_code, uint8_t append_char)
-{
-    if (m_nCodes + m_Early == 4094) {
-        return;
-    }
-    m_CodeArray[m_nCodes ++] = (prefix_code << 16) | append_char;
-    if (m_nCodes + m_Early == 512 - 258) {
-        m_CodeLen = 10;
-    } else if (m_nCodes + m_Early == 1024 - 258) {
-        m_CodeLen = 11;
-    } else if (m_nCodes + m_Early == 2048 - 258) {
-        m_CodeLen = 12;
-    }
-}
-void CLZWDecoder::DecodeString(FX_DWORD code)
-{
+void CLZWDecoder::AddCode(FX_DWORD prefix_code, uint8_t append_char) {
+  if (m_nCodes + m_Early == 4094) {
+    return;
+  }
+  m_CodeArray[m_nCodes++] = (prefix_code << 16) | append_char;
+  if (m_nCodes + m_Early == 512 - 258) {
+    m_CodeLen = 10;
+  } else if (m_nCodes + m_Early == 1024 - 258) {
+    m_CodeLen = 11;
+  } else if (m_nCodes + m_Early == 2048 - 258) {
+    m_CodeLen = 12;
+  }
+}
+void CLZWDecoder::DecodeString(FX_DWORD code) {
+  while (1) {
+    int index = code - 258;
+    if (index < 0 || index >= (int)m_nCodes) {
+      break;
+    }
+    FX_DWORD data = m_CodeArray[index];
+    if (m_StackLen >= sizeof(m_DecodeStack)) {
+      return;
+    }
+    m_DecodeStack[m_StackLen++] = (uint8_t)data;
+    code = data >> 16;
+  }
+  if (m_StackLen >= sizeof(m_DecodeStack)) {
+    return;
+  }
+  m_DecodeStack[m_StackLen++] = (uint8_t)code;
+}
+int CLZWDecoder::Decode(uint8_t* dest_buf,
+                        FX_DWORD& dest_size,
+                        const uint8_t* src_buf,
+                        FX_DWORD& src_size,
+                        FX_BOOL bEarlyChange) {
+  m_CodeLen = 9;
+  m_InPos = 0;
+  m_OutPos = 0;
+  m_pInput = src_buf;
+  m_pOutput = dest_buf;
+  m_Early = bEarlyChange ? 1 : 0;
+  m_nCodes = 0;
+  FX_DWORD old_code = (FX_DWORD)-1;
+  uint8_t last_char;
+  while (1) {
+    if (m_InPos + m_CodeLen > src_size * 8) {
+      break;
+    }
+    int byte_pos = m_InPos / 8;
+    int bit_pos = m_InPos % 8, bit_left = m_CodeLen;
+    FX_DWORD code = 0;
+    if (bit_pos) {
+      bit_left -= 8 - bit_pos;
+      code = (m_pInput[byte_pos++] & ((1 << (8 - bit_pos)) - 1)) << bit_left;
+    }
+    if (bit_left < 8) {
+      code |= m_pInput[byte_pos] >> (8 - bit_left);
+    } else {
+      bit_left -= 8;
+      code |= m_pInput[byte_pos++] << bit_left;
+      if (bit_left) {
+        code |= m_pInput[byte_pos] >> (8 - bit_left);
+      }
+    }
+    m_InPos += m_CodeLen;
+    if (code < 256) {
+      if (m_OutPos == dest_size) {
+        return -5;
+      }
+      if (m_pOutput) {
+        m_pOutput[m_OutPos] = (uint8_t)code;
+      }
+      m_OutPos++;
+      last_char = (uint8_t)code;
+      if (old_code != (FX_DWORD)-1) {
+        AddCode(old_code, last_char);
+      }
+      old_code = code;
+    } else if (code == 256) {
+      m_CodeLen = 9;
+      m_nCodes = 0;
+      old_code = (FX_DWORD)-1;
+    } else if (code == 257) {
+      break;
+    } else {
+      if (old_code == (FX_DWORD)-1) {
+        return 2;
+      }
+      m_StackLen = 0;
+      if (code >= m_nCodes + 258) {
+        if (m_StackLen < sizeof(m_DecodeStack)) {
+          m_DecodeStack[m_StackLen++] = last_char;
+        }
+        DecodeString(old_code);
+      } else {
+        DecodeString(code);
+      }
+      if (m_OutPos + m_StackLen > dest_size) {
+        return -5;
+      }
+      if (m_pOutput) {
+        for (FX_DWORD i = 0; i < m_StackLen; i++) {
+          m_pOutput[m_OutPos + i] = m_DecodeStack[m_StackLen - i - 1];
+        }
+      }
+      m_OutPos += m_StackLen;
+      last_char = m_DecodeStack[m_StackLen - 1];
+      if (old_code < 256) {
+        AddCode(old_code, last_char);
+      } else if (old_code - 258 >= m_nCodes) {
+        dest_size = m_OutPos;
+        src_size = (m_InPos + 7) / 8;
+        return 0;
+      } else {
+        AddCode(old_code, last_char);
+      }
+      old_code = code;
+    }
+  }
+  dest_size = m_OutPos;
+  src_size = (m_InPos + 7) / 8;
+  return 0;
+}
+static uint8_t PaethPredictor(int a, int b, int c) {
+  int p = a + b - c;
+  int pa = FXSYS_abs(p - a);
+  int pb = FXSYS_abs(p - b);
+  int pc = FXSYS_abs(p - c);
+  if (pa <= pb && pa <= pc) {
+    return (uint8_t)a;
+  }
+  if (pb <= pc) {
+    return (uint8_t)b;
+  }
+  return (uint8_t)c;
+}
+static FX_BOOL PNG_PredictorEncode(uint8_t*& data_buf,
+                                   FX_DWORD& data_size,
+                                   int predictor,
+                                   int Colors,
+                                   int BitsPerComponent,
+                                   int Columns) {
+  const int BytesPerPixel = (Colors * BitsPerComponent + 7) / 8;
+  const int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
+  if (row_size <= 0)
+    return FALSE;
+  const int row_count = (data_size + row_size - 1) / row_size;
+  const int last_row_size = data_size % row_size;
+  uint8_t* dest_buf = FX_Alloc2D(uint8_t, row_size + 1, row_count);
+  int byte_cnt = 0;
+  uint8_t* pSrcData = data_buf;
+  uint8_t* pDestData = dest_buf;
+  for (int row = 0; row < row_count; row++) {
+    if (predictor == 10) {
+      pDestData[0] = 0;
+      int move_size = row_size;
+      if (move_size * (row + 1) > (int)data_size) {
+        move_size = data_size - (move_size * row);
+      }
+      FXSYS_memmove(pDestData + 1, pSrcData, move_size);
+      pDestData += (move_size + 1);
+      pSrcData += move_size;
+      byte_cnt += move_size;
+      continue;
+    }
+    for (int byte = 0; byte < row_size && byte_cnt < (int)data_size; byte++) {
+      switch (predictor) {
+        case 11: {
+          pDestData[0] = 1;
+          uint8_t left = 0;
+          if (byte >= BytesPerPixel) {
+            left = pSrcData[byte - BytesPerPixel];
+          }
+          pDestData[byte + 1] = pSrcData[byte] - left;
+        } break;
+        case 12: {
+          pDestData[0] = 2;
+          uint8_t up = 0;
+          if (row) {
+            up = pSrcData[byte - row_size];
+          }
+          pDestData[byte + 1] = pSrcData[byte] - up;
+        } break;
+        case 13: {
+          pDestData[0] = 3;
+          uint8_t left = 0;
+          if (byte >= BytesPerPixel) {
+            left = pSrcData[byte - BytesPerPixel];
+          }
+          uint8_t up = 0;
+          if (row) {
+            up = pSrcData[byte - row_size];
+          }
+          pDestData[byte + 1] = pSrcData[byte] - (left + up) / 2;
+        } break;
+        case 14: {
+          pDestData[0] = 4;
+          uint8_t left = 0;
+          if (byte >= BytesPerPixel) {
+            left = pSrcData[byte - BytesPerPixel];
+          }
+          uint8_t up = 0;
+          if (row) {
+            up = pSrcData[byte - row_size];
+          }
+          uint8_t upper_left = 0;
+          if (byte >= BytesPerPixel && row) {
+            upper_left = pSrcData[byte - row_size - BytesPerPixel];
+          }
+          pDestData[byte + 1] =
+              pSrcData[byte] - PaethPredictor(left, up, upper_left);
+        } break;
+        default: { pDestData[byte + 1] = pSrcData[byte]; } break;
+      }
+      byte_cnt++;
+    }
+    pDestData += (row_size + 1);
+    pSrcData += row_size;
+  }
+  FX_Free(data_buf);
+  data_buf = dest_buf;
+  data_size = (row_size + 1) * row_count -
+              (last_row_size > 0 ? (row_size - last_row_size) : 0);
+  return TRUE;
+}
+static void PNG_PredictLine(uint8_t* pDestData,
+                            const uint8_t* pSrcData,
+                            const uint8_t* pLastLine,
+                            int bpc,
+                            int nColors,
+                            int nPixels) {
+  int row_size = (nPixels * bpc * nColors + 7) / 8;
+  int BytesPerPixel = (bpc * nColors + 7) / 8;
+  uint8_t tag = pSrcData[0];
+  if (tag == 0) {
+    FXSYS_memmove(pDestData, pSrcData + 1, row_size);
+    return;
+  }
+  for (int byte = 0; byte < row_size; byte++) {
+    uint8_t raw_byte = pSrcData[byte + 1];
+    switch (tag) {
+      case 1: {
+        uint8_t left = 0;
+        if (byte >= BytesPerPixel) {
+          left = pDestData[byte - BytesPerPixel];
+        }
+        pDestData[byte] = raw_byte + left;
+        break;
+      }
+      case 2: {
+        uint8_t up = 0;
+        if (pLastLine) {
+          up = pLastLine[byte];
+        }
+        pDestData[byte] = raw_byte + up;
+        break;
+      }
+      case 3: {
+        uint8_t left = 0;
+        if (byte >= BytesPerPixel) {
+          left = pDestData[byte - BytesPerPixel];
+        }
+        uint8_t up = 0;
+        if (pLastLine) {
+          up = pLastLine[byte];
+        }
+        pDestData[byte] = raw_byte + (up + left) / 2;
+        break;
+      }
+      case 4: {
+        uint8_t left = 0;
+        if (byte >= BytesPerPixel) {
+          left = pDestData[byte - BytesPerPixel];
+        }
+        uint8_t up = 0;
+        if (pLastLine) {
+          up = pLastLine[byte];
+        }
+        uint8_t upper_left = 0;
+        if (byte >= BytesPerPixel && pLastLine) {
+          upper_left = pLastLine[byte - BytesPerPixel];
+        }
+        pDestData[byte] = raw_byte + PaethPredictor(left, up, upper_left);
+        break;
+      }
+      default:
+        pDestData[byte] = raw_byte;
+        break;
+    }
+  }
+}
+static FX_BOOL PNG_Predictor(uint8_t*& data_buf,
+                             FX_DWORD& data_size,
+                             int Colors,
+                             int BitsPerComponent,
+                             int Columns) {
+  const int BytesPerPixel = (Colors * BitsPerComponent + 7) / 8;
+  const int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
+  if (row_size <= 0)
+    return FALSE;
+  const int row_count = (data_size + row_size) / (row_size + 1);
+  const int last_row_size = data_size % (row_size + 1);
+  uint8_t* dest_buf = FX_Alloc2D(uint8_t, row_size, row_count);
+  int byte_cnt = 0;
+  uint8_t* pSrcData = data_buf;
+  uint8_t* pDestData = dest_buf;
+  for (int row = 0; row < row_count; row++) {
+    uint8_t tag = pSrcData[0];
+    byte_cnt++;
+    if (tag == 0) {
+      int move_size = row_size;
+      if ((row + 1) * (move_size + 1) > (int)data_size) {
+        move_size = last_row_size - 1;
+      }
+      FXSYS_memmove(pDestData, pSrcData + 1, move_size);
+      pSrcData += move_size + 1;
+      pDestData += move_size;
+      byte_cnt += move_size;
+      continue;
+    }
+    for (int byte = 0; byte < row_size && byte_cnt < (int)data_size; byte++) {
+      uint8_t raw_byte = pSrcData[byte + 1];
+      switch (tag) {
+        case 1: {
+          uint8_t left = 0;
+          if (byte >= BytesPerPixel) {
+            left = pDestData[byte - BytesPerPixel];
+          }
+          pDestData[byte] = raw_byte + left;
+          break;
+        }
+        case 2: {
+          uint8_t up = 0;
+          if (row) {
+            up = pDestData[byte - row_size];
+          }
+          pDestData[byte] = raw_byte + up;
+          break;
+        }
+        case 3: {
+          uint8_t left = 0;
+          if (byte >= BytesPerPixel) {
+            left = pDestData[byte - BytesPerPixel];
+          }
+          uint8_t up = 0;
+          if (row) {
+            up = pDestData[byte - row_size];
+          }
+          pDestData[byte] = raw_byte + (up + left) / 2;
+          break;
+        }
+        case 4: {
+          uint8_t left = 0;
+          if (byte >= BytesPerPixel) {
+            left = pDestData[byte - BytesPerPixel];
+          }
+          uint8_t up = 0;
+          if (row) {
+            up = pDestData[byte - row_size];
+          }
+          uint8_t upper_left = 0;
+          if (byte >= BytesPerPixel && row) {
+            upper_left = pDestData[byte - row_size - BytesPerPixel];
+          }
+          pDestData[byte] = raw_byte + PaethPredictor(left, up, upper_left);
+          break;
+        }
+        default:
+          pDestData[byte] = raw_byte;
+          break;
+      }
+      byte_cnt++;
+    }
+    pSrcData += row_size + 1;
+    pDestData += row_size;
+  }
+  FX_Free(data_buf);
+  data_buf = dest_buf;
+  data_size = row_size * row_count -
+              (last_row_size > 0 ? (row_size + 1 - last_row_size) : 0);
+  return TRUE;
+}
+static void TIFF_PredictorEncodeLine(uint8_t* dest_buf,
+                                     int row_size,
+                                     int BitsPerComponent,
+                                     int Colors,
+                                     int Columns) {
+  int BytesPerPixel = BitsPerComponent * Colors / 8;
+  if (BitsPerComponent < 8) {
+    uint8_t mask = 0x01;
+    if (BitsPerComponent == 2) {
+      mask = 0x03;
+    } else if (BitsPerComponent == 4) {
+      mask = 0x0F;
+    }
+    int row_bits = Colors * BitsPerComponent * Columns;
+    for (int i = row_bits - BitsPerComponent; i >= BitsPerComponent;
+         i -= BitsPerComponent) {
+      int col = i % 8;
+      int index = i / 8;
+      int col_pre =
+          (col == 0) ? (8 - BitsPerComponent) : (col - BitsPerComponent);
+      int index_pre = (col == 0) ? (index - 1) : index;
+      uint8_t cur = (dest_buf[index] >> (8 - col - BitsPerComponent)) & mask;
+      uint8_t left =
+          (dest_buf[index_pre] >> (8 - col_pre - BitsPerComponent)) & mask;
+      cur -= left;
+      cur &= mask;
+      cur <<= (8 - col - BitsPerComponent);
+      dest_buf[index] &= ~(mask << ((8 - col - BitsPerComponent)));
+      dest_buf[index] |= cur;
+    }
+  } else if (BitsPerComponent == 8) {
+    for (int i = row_size - 1; i >= BytesPerPixel; i--) {
+      dest_buf[i] -= dest_buf[i - BytesPerPixel];
+    }
+  } else {
+    for (int i = row_size - BytesPerPixel; i >= BytesPerPixel;
+         i -= BytesPerPixel) {
+      FX_WORD pixel = (dest_buf[i] << 8) | dest_buf[i + 1];
+      pixel -=
+          (dest_buf[i - BytesPerPixel] << 8) | dest_buf[i - BytesPerPixel + 1];
+      dest_buf[i] = pixel >> 8;
+      dest_buf[i + 1] = (uint8_t)pixel;
+    }
+  }
+}
+static FX_BOOL TIFF_PredictorEncode(uint8_t*& data_buf,
+                                    FX_DWORD& data_size,
+                                    int Colors,
+                                    int BitsPerComponent,
+                                    int Columns) {
+  int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
+  if (row_size == 0)
+    return FALSE;
+  const int row_count = (data_size + row_size - 1) / row_size;
+  const int last_row_size = data_size % row_size;
+  for (int row = 0; row < row_count; row++) {
+    uint8_t* scan_line = data_buf + row * row_size;
+    if ((row + 1) * row_size > (int)data_size) {
+      row_size = last_row_size;
+    }
+    TIFF_PredictorEncodeLine(scan_line, row_size, BitsPerComponent, Colors,
+                             Columns);
+  }
+  return TRUE;
+}
+static void TIFF_PredictLine(uint8_t* dest_buf,
+                             int row_size,
+                             int BitsPerComponent,
+                             int Colors,
+                             int Columns) {
+  if (BitsPerComponent == 1) {
+    int row_bits = FX_MIN(BitsPerComponent * Colors * Columns, row_size * 8);
+    int index_pre = 0;
+    int col_pre = 0;
+    for (int i = 1; i < row_bits; i++) {
+      int col = i % 8;
+      int index = i / 8;
+      if (((dest_buf[index] >> (7 - col)) & 1) ^
+          ((dest_buf[index_pre] >> (7 - col_pre)) & 1)) {
+        dest_buf[index] |= 1 << (7 - col);
+      } else {
+        dest_buf[index] &= ~(1 << (7 - col));
+      }
+      index_pre = index;
+      col_pre = col;
+    }
+    return;
+  }
+  int BytesPerPixel = BitsPerComponent * Colors / 8;
+  if (BitsPerComponent == 16) {
+    for (int i = BytesPerPixel; i < row_size; i += 2) {
+      FX_WORD pixel =
+          (dest_buf[i - BytesPerPixel] << 8) | dest_buf[i - BytesPerPixel + 1];
+      pixel += (dest_buf[i] << 8) | dest_buf[i + 1];
+      dest_buf[i] = pixel >> 8;
+      dest_buf[i + 1] = (uint8_t)pixel;
+    }
+  } else {
+    for (int i = BytesPerPixel; i < row_size; i++) {
+      dest_buf[i] += dest_buf[i - BytesPerPixel];
+    }
+  }
+}
+static FX_BOOL TIFF_Predictor(uint8_t*& data_buf,
+                              FX_DWORD& data_size,
+                              int Colors,
+                              int BitsPerComponent,
+                              int Columns) {
+  int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
+  if (row_size == 0)
+    return FALSE;
+  const int row_count = (data_size + row_size - 1) / row_size;
+  const int last_row_size = data_size % row_size;
+  for (int row = 0; row < row_count; row++) {
+    uint8_t* scan_line = data_buf + row * row_size;
+    if ((row + 1) * row_size > (int)data_size) {
+      row_size = last_row_size;
+    }
+    TIFF_PredictLine(scan_line, row_size, BitsPerComponent, Colors, Columns);
+  }
+  return TRUE;
+}
+class CCodec_FlateScanlineDecoder : public CCodec_ScanlineDecoder {
+ public:
+  CCodec_FlateScanlineDecoder();
+  ~CCodec_FlateScanlineDecoder();
+  void Create(const uint8_t* src_buf,
+              FX_DWORD src_size,
+              int width,
+              int height,
+              int nComps,
+              int bpc,
+              int predictor,
+              int Colors,
+              int BitsPerComponent,
+              int Columns);
+  virtual void Destroy() { delete this; }
+  virtual void v_DownScale(int dest_width, int dest_height) {}
+  virtual FX_BOOL v_Rewind();
+  virtual uint8_t* v_GetNextLine();
+  virtual FX_DWORD GetSrcOffset();
+  void* m_pFlate;
+  const uint8_t* m_SrcBuf;
+  FX_DWORD m_SrcSize;
+  uint8_t* m_pScanline;
+  uint8_t* m_pLastLine;
+  uint8_t* m_pPredictBuffer;
+  uint8_t* m_pPredictRaw;
+  int m_Predictor;
+  int m_Colors, m_BitsPerComponent, m_Columns, m_PredictPitch, m_LeftOver;
+};
+CCodec_FlateScanlineDecoder::CCodec_FlateScanlineDecoder() {
+  m_pFlate = NULL;
+  m_pScanline = NULL;
+  m_pLastLine = NULL;
+  m_pPredictBuffer = NULL;
+  m_pPredictRaw = NULL;
+  m_LeftOver = 0;
+}
+CCodec_FlateScanlineDecoder::~CCodec_FlateScanlineDecoder() {
+  if (m_pScanline) {
+    FX_Free(m_pScanline);
+  }
+  if (m_pLastLine) {
+    FX_Free(m_pLastLine);
+  }
+  if (m_pPredictBuffer) {
+    FX_Free(m_pPredictBuffer);
+  }
+  if (m_pPredictRaw) {
+    FX_Free(m_pPredictRaw);
+  }
+  if (m_pFlate) {
+    FPDFAPI_FlateEnd(m_pFlate);
+  }
+}
+void CCodec_FlateScanlineDecoder::Create(const uint8_t* src_buf,
+                                         FX_DWORD src_size,
+                                         int width,
+                                         int height,
+                                         int nComps,
+                                         int bpc,
+                                         int predictor,
+                                         int Colors,
+                                         int BitsPerComponent,
+                                         int Columns) {
+  m_SrcBuf = src_buf;
+  m_SrcSize = src_size;
+  m_OutputWidth = m_OrigWidth = width;
+  m_OutputHeight = m_OrigHeight = height;
+  m_nComps = nComps;
+  m_bpc = bpc;
+  m_bColorTransformed = FALSE;
+  m_Pitch = (width * nComps * bpc + 7) / 8;
+  m_pScanline = FX_Alloc(uint8_t, m_Pitch);
+  m_Predictor = 0;
+  if (predictor) {
+    if (predictor >= 10) {
+      m_Predictor = 2;
+    } else if (predictor == 2) {
+      m_Predictor = 1;
+    }
+    if (m_Predictor) {
+      if (BitsPerComponent * Colors * Columns == 0) {
+        BitsPerComponent = m_bpc;
+        Colors = m_nComps;
+        Columns = m_OrigWidth;
+      }
+      m_Colors = Colors;
+      m_BitsPerComponent = BitsPerComponent;
+      m_Columns = Columns;
+      m_PredictPitch = (m_BitsPerComponent * m_Colors * m_Columns + 7) / 8;
+      m_pLastLine = FX_Alloc(uint8_t, m_PredictPitch);
+      m_pPredictRaw = FX_Alloc(uint8_t, m_PredictPitch + 1);
+      m_pPredictBuffer = FX_Alloc(uint8_t, m_PredictPitch);
+    }
+  }
+}
+FX_BOOL CCodec_FlateScanlineDecoder::v_Rewind() {
+  if (m_pFlate) {
+    FPDFAPI_FlateEnd(m_pFlate);
+  }
+  m_pFlate = FPDFAPI_FlateInit(my_alloc_func, my_free_func);
+  if (m_pFlate == NULL) {
+    return FALSE;
+  }
+  FPDFAPI_FlateInput(m_pFlate, m_SrcBuf, m_SrcSize);
+  m_LeftOver = 0;
+  return TRUE;
+}
+uint8_t* CCodec_FlateScanlineDecoder::v_GetNextLine() {
+  if (m_Predictor) {
+    if (m_Pitch == m_PredictPitch) {
+      if (m_Predictor == 2) {
+        FPDFAPI_FlateOutput(m_pFlate, m_pPredictRaw, m_PredictPitch + 1);
+        PNG_PredictLine(m_pScanline, m_pPredictRaw, m_pLastLine,
+                        m_BitsPerComponent, m_Colors, m_Columns);
+        FXSYS_memcpy(m_pLastLine, m_pScanline, m_PredictPitch);
+      } else {
+        FPDFAPI_FlateOutput(m_pFlate, m_pScanline, m_Pitch);
+        TIFF_PredictLine(m_pScanline, m_PredictPitch, m_bpc, m_nComps,
+                         m_OutputWidth);
+      }
+    } else {
+      int bytes_to_go = m_Pitch;
+      int read_leftover = m_LeftOver > bytes_to_go ? bytes_to_go : m_LeftOver;
+      if (read_leftover) {
+        FXSYS_memcpy(m_pScanline,
+                     m_pPredictBuffer + m_PredictPitch - m_LeftOver,
+                     read_leftover);
+        m_LeftOver -= read_leftover;
+        bytes_to_go -= read_leftover;
+      }
+      while (bytes_to_go) {
+        if (m_Predictor == 2) {
+          FPDFAPI_FlateOutput(m_pFlate, m_pPredictRaw, m_PredictPitch + 1);
+          PNG_PredictLine(m_pPredictBuffer, m_pPredictRaw, m_pLastLine,
+                          m_BitsPerComponent, m_Colors, m_Columns);
+          FXSYS_memcpy(m_pLastLine, m_pPredictBuffer, m_PredictPitch);
+        } else {
+          FPDFAPI_FlateOutput(m_pFlate, m_pPredictBuffer, m_PredictPitch);
+          TIFF_PredictLine(m_pPredictBuffer, m_PredictPitch, m_BitsPerComponent,
+                           m_Colors, m_Columns);
+        }
+        int read_bytes =
+            m_PredictPitch > bytes_to_go ? bytes_to_go : m_PredictPitch;
+        FXSYS_memcpy(m_pScanline + m_Pitch - bytes_to_go, m_pPredictBuffer,
+                     read_bytes);
+        m_LeftOver += m_PredictPitch - read_bytes;
+        bytes_to_go -= read_bytes;
+      }
+    }
+  } else {
+    FPDFAPI_FlateOutput(m_pFlate, m_pScanline, m_Pitch);
+  }
+  return m_pScanline;
+}
+FX_DWORD CCodec_FlateScanlineDecoder::GetSrcOffset() {
+  return FPDFAPI_FlateGetTotalIn(m_pFlate);
+}
+static void FlateUncompress(const uint8_t* src_buf,
+                            FX_DWORD src_size,
+                            FX_DWORD orig_size,
+                            uint8_t*& dest_buf,
+                            FX_DWORD& dest_size,
+                            FX_DWORD& offset) {
+  const FX_BOOL useOldImpl = src_size < 10240;
+  FX_DWORD guess_size = orig_size ? orig_size : src_size * 2;
+  FX_DWORD alloc_step =
+      orig_size ? 10240 : (src_size < 10240 ? 10240 : src_size);
+  static const FX_DWORD kMaxInitialAllocSize = 10000000;
+  if (guess_size > kMaxInitialAllocSize) {
+    guess_size = kMaxInitialAllocSize;
+    alloc_step = kMaxInitialAllocSize;
+  }
+  FX_DWORD buf_size = guess_size;
+  FX_DWORD last_buf_size = buf_size;
+  void* context = nullptr;
+
+  uint8_t* guess_buf = FX_Alloc(uint8_t, guess_size + 1);
+  uint8_t* cur_buf = guess_buf;
+  guess_buf[guess_size] = '\0';
+  context = FPDFAPI_FlateInit(my_alloc_func, my_free_func);
+  if (!context)
+    goto fail;
+  FPDFAPI_FlateInput(context, src_buf, src_size);
+  if (useOldImpl) {
     while (1) {
-        int index = code - 258;
-        if (index < 0 || index >= (int)m_nCodes) {
-            break;
-        }
-        FX_DWORD data = m_CodeArray[index];
-        if (m_StackLen >= sizeof(m_DecodeStack)) {
-            return;
-        }
-        m_DecodeStack[m_StackLen++] = (uint8_t)data;
-        code = data >> 16;
-    }
-    if (m_StackLen >= sizeof(m_DecodeStack)) {
-        return;
-    }
-    m_DecodeStack[m_StackLen++] = (uint8_t)code;
-}
-int CLZWDecoder::Decode(uint8_t* dest_buf, FX_DWORD& dest_size, const uint8_t* src_buf, FX_DWORD& src_size, FX_BOOL bEarlyChange)
-{
-    m_CodeLen = 9;
-    m_InPos = 0;
-    m_OutPos = 0;
-    m_pInput = src_buf;
-    m_pOutput = dest_buf;
-    m_Early = bEarlyChange ? 1 : 0;
-    m_nCodes = 0;
-    FX_DWORD old_code = (FX_DWORD) - 1;
-    uint8_t last_char;
+      int32_t ret = FPDFAPI_FlateOutput(context, cur_buf, buf_size);
+      if (ret != Z_OK)
+        break;
+      int32_t avail_buf_size = FPDFAPI_FlateGetAvailOut(context);
+      if (avail_buf_size != 0)
+        break;
+
+      // |avail_buf_size| == 0 case.
+      FX_DWORD old_size = guess_size;
+      guess_size += alloc_step;
+      if (guess_size < old_size || guess_size + 1 < guess_size)
+        goto fail;
+      guess_buf = FX_Realloc(uint8_t, guess_buf, guess_size + 1);
+      if (!guess_buf)
+        goto fail;
+      guess_buf[guess_size] = '\0';
+      cur_buf = guess_buf + old_size;
+      buf_size = guess_size - old_size;
+    }
+    dest_size = FPDFAPI_FlateGetTotalOut(context);
+    offset = FPDFAPI_FlateGetTotalIn(context);
+    if (guess_size / 2 > dest_size) {
+      guess_buf = FX_Realloc(uint8_t, guess_buf, dest_size + 1);
+      if (!guess_buf)
+        goto fail;
+      guess_size = dest_size;
+      guess_buf[guess_size] = '\0';
+    }
+    dest_buf = guess_buf;
+  } else {
+    CFX_ArrayTemplate<uint8_t*> result_tmp_bufs;
     while (1) {
-        if (m_InPos + m_CodeLen > src_size * 8) {
-            break;
-        }
-        int byte_pos = m_InPos / 8;
-        int bit_pos = m_InPos % 8, bit_left = m_CodeLen;
-        FX_DWORD code = 0;
-        if (bit_pos) {
-            bit_left -= 8 - bit_pos;
-            code = (m_pInput[byte_pos++] & ((1 << (8 - bit_pos)) - 1)) << bit_left;
-        }
-        if (bit_left < 8) {
-            code |= m_pInput[byte_pos] >> (8 - bit_left);
-        } else {
-            bit_left -= 8;
-            code |= m_pInput[byte_pos++] << bit_left;
-            if (bit_left) {
-                code |= m_pInput[byte_pos] >> (8 - bit_left);
-            }
-        }
-        m_InPos += m_CodeLen;
-        if (code < 256) {
-            if (m_OutPos == dest_size) {
-                return -5;
-            }
-            if (m_pOutput) {
-                m_pOutput[m_OutPos] = (uint8_t)code;
-            }
-            m_OutPos ++;
-            last_char = (uint8_t)code;
-            if (old_code != (FX_DWORD) - 1) {
-                AddCode(old_code, last_char);
-            }
-            old_code = code;
-        } else if (code == 256) {
-            m_CodeLen = 9;
-            m_nCodes = 0;
-            old_code = (FX_DWORD) - 1;
-        } else if (code == 257) {
-            break;
-        } else {
-            if (old_code == (FX_DWORD) - 1) {
-                return 2;
-            }
-            m_StackLen = 0;
-            if (code >= m_nCodes + 258) {
-                if (m_StackLen < sizeof(m_DecodeStack)) {
-                    m_DecodeStack[m_StackLen++] = last_char;
-                }
-                DecodeString(old_code);
-            } else {
-                DecodeString(code);
-            }
-            if (m_OutPos + m_StackLen > dest_size) {
-                return -5;
-            }
-            if (m_pOutput) {
-                for (FX_DWORD i = 0; i < m_StackLen; i ++) {
-                    m_pOutput[m_OutPos + i] = m_DecodeStack[m_StackLen - i - 1];
-                }
-            }
-            m_OutPos += m_StackLen;
-            last_char = m_DecodeStack[m_StackLen - 1];
-            if (old_code < 256) {
-                AddCode(old_code, last_char);
-            } else if (old_code - 258 >= m_nCodes) {
-                dest_size = m_OutPos;
-                src_size = (m_InPos + 7) / 8;
-                return 0;
-            } else {
-                AddCode(old_code, last_char);
-            }
-            old_code = code;
-        }
-    }
-    dest_size = m_OutPos;
-    src_size = (m_InPos + 7) / 8;
-    return 0;
-}
-static uint8_t PaethPredictor(int a, int b, int c)
-{
-    int p = a + b - c;
-    int pa = FXSYS_abs(p - a);
-    int pb = FXSYS_abs(p - b);
-    int pc = FXSYS_abs(p - c);
-    if (pa <= pb && pa <= pc) {
-        return (uint8_t)a;
-    }
-    if (pb <= pc) {
-        return (uint8_t)b;
-    }
-    return (uint8_t)c;
-}
-static FX_BOOL PNG_PredictorEncode(uint8_t*& data_buf, FX_DWORD& data_size,
-                                   int predictor, int Colors,
-                                   int BitsPerComponent, int Columns)
-{
-    const int BytesPerPixel = (Colors * BitsPerComponent + 7) / 8;
-    const int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
-    if (row_size <= 0)
-        return FALSE;
-    const int row_count = (data_size + row_size - 1) / row_size;
-    const int last_row_size = data_size % row_size;
-    uint8_t* dest_buf = FX_Alloc2D(uint8_t, row_size + 1, row_count);
-    int byte_cnt = 0;
-    uint8_t* pSrcData = data_buf;
-    uint8_t* pDestData = dest_buf;
-    for (int row = 0; row < row_count; row++) {
-        if (predictor == 10) {
-            pDestData[0] = 0;
-            int move_size = row_size;
-            if (move_size * (row + 1) > (int)data_size) {
-                move_size = data_size - (move_size * row);
-            }
-            FXSYS_memmove(pDestData + 1, pSrcData, move_size);
-            pDestData += (move_size + 1);
-            pSrcData += move_size;
-            byte_cnt += move_size;
-            continue;
-        }
-        for (int byte = 0; byte < row_size && byte_cnt < (int)data_size; byte++) {
-            switch (predictor) {
-                case 11: {
-                        pDestData[0] = 1;
-                        uint8_t left = 0;
-                        if (byte >= BytesPerPixel) {
-                            left = pSrcData[byte - BytesPerPixel];
-                        }
-                        pDestData[byte + 1] = pSrcData[byte] - left;
-                    }
-                    break;
-                case 12: {
-                        pDestData[0] = 2;
-                        uint8_t up = 0;
-                        if (row) {
-                            up = pSrcData[byte - row_size];
-                        }
-                        pDestData[byte + 1] = pSrcData[byte] - up;
-                    }
-                    break;
-                case 13: {
-                        pDestData[0] = 3;
-                        uint8_t left = 0;
-                        if (byte >= BytesPerPixel) {
-                            left = pSrcData[byte - BytesPerPixel];
-                        }
-                        uint8_t up = 0;
-                        if (row) {
-                            up = pSrcData[byte - row_size];
-                        }
-                        pDestData[byte + 1] = pSrcData[byte] - (left + up) / 2;
-                    }
-                    break;
-                case 14: {
-                        pDestData[0] = 4;
-                        uint8_t left = 0;
-                        if (byte >= BytesPerPixel) {
-                            left = pSrcData[byte - BytesPerPixel];
-                        }
-                        uint8_t up = 0;
-                        if (row) {
-                            up = pSrcData[byte - row_size];
-                        }
-                        uint8_t upper_left = 0;
-                        if (byte >= BytesPerPixel && row) {
-                            upper_left = pSrcData[byte - row_size - BytesPerPixel];
-                        }
-                        pDestData[byte + 1] = pSrcData[byte] - PaethPredictor(left, up, upper_left);
-                    }
-                    break;
-                default: {
-                        pDestData[byte + 1] = pSrcData[byte];
-                    }
-                    break;
-            }
-            byte_cnt++;
-        }
-        pDestData += (row_size + 1);
-        pSrcData += row_size;
-    }
-    FX_Free(data_buf);
-    data_buf = dest_buf;
-    data_size = (row_size + 1) * row_count - (last_row_size > 0 ? (row_size - last_row_size) : 0);
-    return TRUE;
-}
-static void PNG_PredictLine(uint8_t* pDestData, const uint8_t* pSrcData, const uint8_t* pLastLine,
-                            int bpc, int nColors, int nPixels)
-{
-    int row_size = (nPixels * bpc * nColors + 7) / 8;
-    int BytesPerPixel = (bpc * nColors + 7) / 8;
-    uint8_t tag = pSrcData[0];
-    if (tag == 0) {
-        FXSYS_memmove(pDestData, pSrcData + 1, row_size);
-        return;
-    }
-    for (int byte = 0; byte < row_size; byte ++) {
-        uint8_t raw_byte = pSrcData[byte + 1];
-        switch (tag) {
-            case 1:     {
-                    uint8_t left = 0;
-                    if (byte >= BytesPerPixel) {
-                        left = pDestData[byte - BytesPerPixel];
-                    }
-                    pDestData[byte] = raw_byte + left;
-                    break;
-                }
-            case 2: {
-                    uint8_t up = 0;
-                    if (pLastLine) {
-                        up = pLastLine[byte];
-                    }
-                    pDestData[byte] = raw_byte + up;
-                    break;
-                }
-            case 3: {
-                    uint8_t left = 0;
-                    if (byte >= BytesPerPixel) {
-                        left = pDestData[byte - BytesPerPixel];
-                    }
-                    uint8_t up = 0;
-                    if (pLastLine) {
-                        up = pLastLine[byte];
-                    }
-                    pDestData[byte] = raw_byte + (up + left) / 2;
-                    break;
-                }
-            case 4: {
-                    uint8_t left = 0;
-                    if (byte >= BytesPerPixel) {
-                        left = pDestData[byte - BytesPerPixel];
-                    }
-                    uint8_t up = 0;
-                    if (pLastLine) {
-                        up = pLastLine[byte];
-                    }
-                    uint8_t upper_left = 0;
-                    if (byte >= BytesPerPixel && pLastLine) {
-                        upper_left = pLastLine[byte - BytesPerPixel];
-                    }
-                    pDestData[byte] = raw_byte + PaethPredictor(left, up, upper_left);
-                    break;
-                }
-            default:
-                pDestData[byte] = raw_byte;
-                break;
-        }
-    }
-}
-static FX_BOOL PNG_Predictor(uint8_t*& data_buf, FX_DWORD& data_size,
-                             int Colors, int BitsPerComponent, int Columns)
-{
-    const int BytesPerPixel = (Colors * BitsPerComponent + 7) / 8;
-    const int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
-    if (row_size <= 0)
-        return FALSE;
-    const int row_count = (data_size + row_size) / (row_size + 1);
-    const int last_row_size = data_size % (row_size + 1);
-    uint8_t* dest_buf = FX_Alloc2D(uint8_t, row_size, row_count);
-    int byte_cnt = 0;
-    uint8_t* pSrcData = data_buf;
-    uint8_t* pDestData = dest_buf;
-    for (int row = 0; row < row_count; row ++) {
-        uint8_t tag = pSrcData[0];
-        byte_cnt++;
-        if (tag == 0) {
-            int move_size = row_size;
-            if ((row + 1) * (move_size + 1) > (int)data_size) {
-                move_size = last_row_size - 1;
-            }
-            FXSYS_memmove(pDestData, pSrcData + 1, move_size);
-            pSrcData += move_size + 1;
-            pDestData += move_size;
-            byte_cnt += move_size;
-            continue;
-        }
-        for (int byte = 0; byte < row_size && byte_cnt < (int)data_size; byte ++) {
-            uint8_t raw_byte = pSrcData[byte + 1];
-            switch (tag) {
-                case 1: {
-                        uint8_t left = 0;
-                        if (byte >= BytesPerPixel) {
-                            left = pDestData[byte - BytesPerPixel];
-                        }
-                        pDestData[byte] = raw_byte + left;
-                        break;
-                    }
-                case 2: {
-                        uint8_t up = 0;
-                        if (row) {
-                            up = pDestData[byte - row_size];
-                        }
-                        pDestData[byte] = raw_byte + up;
-                        break;
-                    }
-                case 3: {
-                        uint8_t left = 0;
-                        if (byte >= BytesPerPixel) {
-                            left = pDestData[byte - BytesPerPixel];
-                        }
-                        uint8_t up = 0;
-                        if (row) {
-                            up = pDestData[byte - row_size];
-                        }
-                        pDestData[byte] = raw_byte + (up + left) / 2;
-                        break;
-                    }
-                case 4: {
-                        uint8_t left = 0;
-                        if (byte >= BytesPerPixel) {
-                            left = pDestData[byte - BytesPerPixel];
-                        }
-                        uint8_t up = 0;
-                        if (row) {
-                            up = pDestData[byte - row_size];
-                        }
-                        uint8_t upper_left = 0;
-                        if (byte >= BytesPerPixel && row) {
-                            upper_left = pDestData[byte - row_size - BytesPerPixel];
-                        }
-                        pDestData[byte] = raw_byte + PaethPredictor(left, up, upper_left);
-                        break;
-                    }
-                default:
-                    pDestData[byte] = raw_byte;
-                    break;
-            }
-            byte_cnt++;
-        }
-        pSrcData += row_size + 1;
-        pDestData += row_size;
-    }
-    FX_Free(data_buf);
-    data_buf = dest_buf;
-    data_size = row_size * row_count - (last_row_size > 0 ? (row_size + 1 - last_row_size) : 0);
-    return TRUE;
-}
-static void TIFF_PredictorEncodeLine(uint8_t* dest_buf, int row_size, int BitsPerComponent, int Colors, int Columns)
-{
-    int BytesPerPixel = BitsPerComponent * Colors / 8;
-    if (BitsPerComponent < 8) {
-        uint8_t mask = 0x01;
-        if (BitsPerComponent == 2) {
-            mask = 0x03;
-        } else if (BitsPerComponent == 4) {
-            mask = 0x0F;
-        }
-        int row_bits = Colors * BitsPerComponent * Columns;
-        for (int i = row_bits - BitsPerComponent; i >= BitsPerComponent; i -= BitsPerComponent) {
-            int col = i % 8;
-            int index = i / 8;
-            int col_pre = (col == 0) ? (8 - BitsPerComponent) : (col - BitsPerComponent);
-            int index_pre = (col == 0) ? (index - 1) : index;
-            uint8_t cur = (dest_buf[index] >> (8 - col - BitsPerComponent)) & mask;
-            uint8_t left = (dest_buf[index_pre] >> (8 - col_pre - BitsPerComponent)) & mask;
-            cur -= left;
-            cur &= mask;
-            cur <<= (8 - col - BitsPerComponent);
-            dest_buf[index] &= ~(mask << ((8 - col - BitsPerComponent)));
-            dest_buf[index] |= cur;
-        }
-    } else if (BitsPerComponent == 8) {
-        for (int i = row_size - 1; i >= BytesPerPixel; i--) {
-            dest_buf[i] -= dest_buf[i - BytesPerPixel];
-        }
+      int32_t ret = FPDFAPI_FlateOutput(context, cur_buf, buf_size);
+      int32_t avail_buf_size = FPDFAPI_FlateGetAvailOut(context);
+      if (ret != Z_OK) {
+        last_buf_size = buf_size - avail_buf_size;
+        result_tmp_bufs.Add(cur_buf);
+        break;
+      }
+      if (avail_buf_size != 0) {
+        last_buf_size = buf_size - avail_buf_size;
+        result_tmp_bufs.Add(cur_buf);
+        break;
+      }
+
+      // |avail_buf_size| == 0 case.
+      result_tmp_bufs.Add(cur_buf);
+      cur_buf = FX_Alloc(uint8_t, buf_size + 1);
+      cur_buf[buf_size] = '\0';
+    }
+    dest_size = FPDFAPI_FlateGetTotalOut(context);
+    offset = FPDFAPI_FlateGetTotalIn(context);
+    if (result_tmp_bufs.GetSize() == 1) {
+      dest_buf = result_tmp_bufs[0];
     } else {
-        for (int i = row_size - BytesPerPixel; i >= BytesPerPixel; i -= BytesPerPixel) {
-            FX_WORD pixel = (dest_buf[i] << 8) | dest_buf[i + 1];
-            pixel -= (dest_buf[i - BytesPerPixel] << 8) | dest_buf[i - BytesPerPixel + 1];
-            dest_buf[i] = pixel >> 8;
-            dest_buf[i + 1] = (uint8_t)pixel;
-        }
-    }
-}
-static FX_BOOL TIFF_PredictorEncode(uint8_t*& data_buf, FX_DWORD& data_size,
-                                    int Colors, int BitsPerComponent, int Columns)
-{
-    int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
-    if (row_size == 0)
-        return FALSE;
-    const int row_count = (data_size + row_size - 1) / row_size;
-    const int last_row_size = data_size % row_size;
-    for (int row = 0; row < row_count; row++) {
-        uint8_t* scan_line = data_buf + row * row_size;
-        if ((row + 1) * row_size > (int)data_size) {
-            row_size = last_row_size;
-        }
-        TIFF_PredictorEncodeLine(scan_line, row_size, BitsPerComponent, Colors, Columns);
-    }
-    return TRUE;
-}
-static void TIFF_PredictLine(uint8_t* dest_buf, int row_size, int BitsPerComponent, int Colors, int Columns)
-{
-    if (BitsPerComponent == 1) {
-        int row_bits = FX_MIN(BitsPerComponent * Colors * Columns, row_size * 8);
-        int index_pre = 0;
-        int col_pre = 0;
-        for(int i = 1; i < row_bits; i ++) {
-            int col = i % 8;
-            int index = i / 8;
-            if( ((dest_buf[index] >> (7 - col)) & 1) ^ ((dest_buf[index_pre] >> (7 - col_pre)) & 1) ) {
-                dest_buf[index] |= 1 << (7 - col);
-            } else {
-                dest_buf[index] &= ~(1 << (7 - col));
-            }
-            index_pre = index;
-            col_pre = col;
-        }
-        return;
-    }
-    int BytesPerPixel = BitsPerComponent * Colors / 8;
-    if (BitsPerComponent == 16) {
-        for (int i = BytesPerPixel; i < row_size; i += 2) {
-            FX_WORD pixel = (dest_buf[i - BytesPerPixel] << 8) | dest_buf[i - BytesPerPixel + 1];
-            pixel += (dest_buf[i] << 8) | dest_buf[i + 1];
-            dest_buf[i] = pixel >> 8;
-            dest_buf[i + 1] = (uint8_t)pixel;
-        }
-    } else {
-        for (int i = BytesPerPixel; i < row_size; i ++) {
-            dest_buf[i] += dest_buf[i - BytesPerPixel];
-        }
-    }
-}
-static FX_BOOL TIFF_Predictor(uint8_t*& data_buf, FX_DWORD& data_size,
-                              int Colors, int BitsPerComponent, int Columns)
-{
-    int row_size = (Colors * BitsPerComponent * Columns + 7) / 8;
-    if (row_size == 0)
-        return FALSE;
-    const int row_count = (data_size + row_size - 1) / row_size;
-    const int last_row_size = data_size % row_size;
-    for (int row = 0; row < row_count; row ++) {
-        uint8_t* scan_line = data_buf + row * row_size;
-        if ((row + 1) * row_size > (int)data_size) {
-            row_size = last_row_size;
-        }
-        TIFF_PredictLine(scan_line, row_size, BitsPerComponent, Colors, Columns);
-    }
-    return TRUE;
-}
-class CCodec_FlateScanlineDecoder : public CCodec_ScanlineDecoder
-{
-public:
-    CCodec_FlateScanlineDecoder();
-    ~CCodec_FlateScanlineDecoder();
-    void Create(const uint8_t* src_buf, FX_DWORD src_size, int width, int height, int nComps, int bpc,
-                int predictor, int Colors, int BitsPerComponent, int Columns);
-    virtual void                Destroy()
-    {
-        delete this;
-    }
-    virtual void                v_DownScale(int dest_width, int dest_height) {}
-    virtual FX_BOOL             v_Rewind();
-    virtual uint8_t*    v_GetNextLine();
-    virtual FX_DWORD    GetSrcOffset();
-    void*                               m_pFlate;
-    const uint8_t*                      m_SrcBuf;
-    FX_DWORD                    m_SrcSize;
-    uint8_t*                    m_pScanline;
-    uint8_t*                    m_pLastLine;
-    uint8_t*                    m_pPredictBuffer;
-    uint8_t*                    m_pPredictRaw;
-    int                                 m_Predictor;
-    int                                 m_Colors, m_BitsPerComponent, m_Columns, m_PredictPitch, m_LeftOver;
-};
-CCodec_FlateScanlineDecoder::CCodec_FlateScanlineDecoder()
-{
-    m_pFlate = NULL;
-    m_pScanline = NULL;
-    m_pLastLine = NULL;
-    m_pPredictBuffer = NULL;
-    m_pPredictRaw = NULL;
-    m_LeftOver = 0;
-}
-CCodec_FlateScanlineDecoder::~CCodec_FlateScanlineDecoder()
-{
-    if (m_pScanline) {
-        FX_Free(m_pScanline);
-    }
-    if (m_pLastLine) {
-        FX_Free(m_pLastLine);
-    }
-    if (m_pPredictBuffer) {
-        FX_Free(m_pPredictBuffer);
-    }
-    if (m_pPredictRaw) {
-        FX_Free(m_pPredictRaw);
-    }
-    if (m_pFlate) {
-        FPDFAPI_FlateEnd(m_pFlate);
-    }
-}
-void CCodec_FlateScanlineDecoder::Create(const uint8_t* src_buf, FX_DWORD src_size, int width, int height,
-        int nComps, int bpc, int predictor, int Colors, int BitsPerComponent, int Columns)
-{
-    m_SrcBuf = src_buf;
-    m_SrcSize = src_size;
-    m_OutputWidth = m_OrigWidth = width;
-    m_OutputHeight = m_OrigHeight = height;
-    m_nComps = nComps;
-    m_bpc = bpc;
-    m_bColorTransformed = FALSE;
-    m_Pitch = (width * nComps * bpc + 7) / 8;
-    m_pScanline = FX_Alloc(uint8_t, m_Pitch);
-    m_Predictor = 0;
-    if (predictor) {
-        if (predictor >= 10) {
-            m_Predictor = 2;
-        } else if (predictor == 2) {
-            m_Predictor = 1;
-        }
-        if (m_Predictor) {
-            if (BitsPerComponent * Colors * Columns == 0) {
-                BitsPerComponent = m_bpc;
-                Colors = m_nComps;
-                Columns = m_OrigWidth;
-            }
-            m_Colors = Colors;
-            m_BitsPerComponent = BitsPerComponent;
-            m_Columns = Columns;
-            m_PredictPitch = (m_BitsPerComponent * m_Colors * m_Columns + 7) / 8;
-            m_pLastLine = FX_Alloc(uint8_t, m_PredictPitch);
-            m_pPredictRaw = FX_Alloc(uint8_t, m_PredictPitch + 1);
-            m_pPredictBuffer = FX_Alloc(uint8_t, m_PredictPitch);
-        }
-    }
-}
-FX_BOOL CCodec_FlateScanlineDecoder::v_Rewind()
-{
-    if (m_pFlate) {
-        FPDFAPI_FlateEnd(m_pFlate);
-    }
-    m_pFlate = FPDFAPI_FlateInit(my_alloc_func, my_free_func);
-    if (m_pFlate == NULL) {
-        return FALSE;
-    }
-    FPDFAPI_FlateInput(m_pFlate, m_SrcBuf, m_SrcSize);
-    m_LeftOver = 0;
-    return TRUE;
-}
-uint8_t* CCodec_FlateScanlineDecoder::v_GetNextLine()
-{
-    if (m_Predictor) {
-        if (m_Pitch == m_PredictPitch) {
-            if (m_Predictor == 2) {
-                FPDFAPI_FlateOutput(m_pFlate, m_pPredictRaw, m_PredictPitch + 1);
-                PNG_PredictLine(m_pScanline, m_pPredictRaw, m_pLastLine, m_BitsPerComponent, m_Colors, m_Columns);
-                FXSYS_memcpy(m_pLastLine, m_pScanline, m_PredictPitch);
-            } else {
-                FPDFAPI_FlateOutput(m_pFlate, m_pScanline, m_Pitch);
-                TIFF_PredictLine(m_pScanline, m_PredictPitch, m_bpc, m_nComps, m_OutputWidth);
-            }
-        } else {
-            int bytes_to_go = m_Pitch;
-            int read_leftover = m_LeftOver > bytes_to_go ? bytes_to_go : m_LeftOver;
-            if (read_leftover) {
-                FXSYS_memcpy(m_pScanline, m_pPredictBuffer + m_PredictPitch - m_LeftOver, read_leftover);
-                m_LeftOver -= read_leftover;
-                bytes_to_go -= read_leftover;
-            }
-            while (bytes_to_go) {
-                if (m_Predictor == 2) {
-                    FPDFAPI_FlateOutput(m_pFlate, m_pPredictRaw, m_PredictPitch + 1);
-                    PNG_PredictLine(m_pPredictBuffer, m_pPredictRaw, m_pLastLine, m_BitsPerComponent, m_Colors, m_Columns);
-                    FXSYS_memcpy(m_pLastLine, m_pPredictBuffer, m_PredictPitch);
-                } else {
-                    FPDFAPI_FlateOutput(m_pFlate, m_pPredictBuffer, m_PredictPitch);
-                    TIFF_PredictLine(m_pPredictBuffer, m_PredictPitch, m_BitsPerComponent, m_Colors, m_Columns);
-                }
-                int read_bytes = m_PredictPitch > bytes_to_go ? bytes_to_go : m_PredictPitch;
-                FXSYS_memcpy(m_pScanline + m_Pitch - bytes_to_go, m_pPredictBuffer, read_bytes);
-                m_LeftOver += m_PredictPitch - read_bytes;
-                bytes_to_go -= read_bytes;
-            }
-        }
-    } else {
-        FPDFAPI_FlateOutput(m_pFlate, m_pScanline, m_Pitch);
-    }
-    return m_pScanline;
-}
-FX_DWORD CCodec_FlateScanlineDecoder::GetSrcOffset()
-{
-    return FPDFAPI_FlateGetTotalIn(m_pFlate);
-}
-static void FlateUncompress(const uint8_t* src_buf, FX_DWORD src_size, FX_DWORD orig_size,
-                            uint8_t*& dest_buf, FX_DWORD& dest_size, FX_DWORD& offset)
-{
-    const FX_BOOL useOldImpl = src_size < 10240;
-    FX_DWORD guess_size = orig_size ? orig_size : src_size * 2;
-    FX_DWORD alloc_step = orig_size ? 10240 : (src_size < 10240 ? 10240 : src_size);
-    static const FX_DWORD kMaxInitialAllocSize = 10000000;
-    if (guess_size > kMaxInitialAllocSize) {
-        guess_size = kMaxInitialAllocSize;
-        alloc_step = kMaxInitialAllocSize;
-    }
-    FX_DWORD buf_size = guess_size;
-    FX_DWORD last_buf_size = buf_size;
-    void* context = nullptr;
-
-    uint8_t* guess_buf = FX_Alloc(uint8_t, guess_size + 1);
-    uint8_t* cur_buf = guess_buf;
-    guess_buf[guess_size] = '\0';
-    context = FPDFAPI_FlateInit(my_alloc_func, my_free_func);
-    if (!context)
-        goto fail;
-    FPDFAPI_FlateInput(context, src_buf, src_size);
-    if (useOldImpl) {
-        while (1) {
-            int32_t ret = FPDFAPI_FlateOutput(context, cur_buf, buf_size);
-            if (ret != Z_OK)
-                break;
-            int32_t avail_buf_size = FPDFAPI_FlateGetAvailOut(context);
-            if (avail_buf_size != 0)
-                break;
-
-            // |avail_buf_size| == 0 case.
-            FX_DWORD old_size = guess_size;
-            guess_size += alloc_step;
-            if (guess_size < old_size || guess_size + 1 < guess_size)
-                goto fail;
-            guess_buf = FX_Realloc(uint8_t, guess_buf, guess_size + 1);
-            if (!guess_buf)
-                goto fail;
-            guess_buf[guess_size] = '\0';
-            cur_buf = guess_buf + old_size;
-            buf_size = guess_size - old_size;
-        }
-        dest_size = FPDFAPI_FlateGetTotalOut(context);
-        offset = FPDFAPI_FlateGetTotalIn(context);
-        if (guess_size / 2 > dest_size) {
-            guess_buf = FX_Realloc(uint8_t, guess_buf, dest_size + 1);
-            if (!guess_buf)
-                goto fail;
-            guess_size = dest_size;
-            guess_buf[guess_size] = '\0';
-        }
-        dest_buf = guess_buf;
-    } else {
-        CFX_ArrayTemplate<uint8_t*> result_tmp_bufs;
-        while (1) {
-            int32_t ret = FPDFAPI_FlateOutput(context, cur_buf, buf_size);
-            int32_t avail_buf_size = FPDFAPI_FlateGetAvailOut(context);
-            if (ret != Z_OK) {
-                last_buf_size = buf_size - avail_buf_size;
-                result_tmp_bufs.Add(cur_buf);
-                break;
-            }
-            if (avail_buf_size != 0) {
-                last_buf_size = buf_size - avail_buf_size;
-                result_tmp_bufs.Add(cur_buf);
-                break;
-            }
-
-            // |avail_buf_size| == 0 case.
-            result_tmp_bufs.Add(cur_buf);
-            cur_buf = FX_Alloc(uint8_t, buf_size + 1);
-            cur_buf[buf_size] = '\0';
-        }
-        dest_size = FPDFAPI_FlateGetTotalOut(context);
-        offset = FPDFAPI_FlateGetTotalIn(context);
-        if (result_tmp_bufs.GetSize() == 1) {
-            dest_buf = result_tmp_bufs[0];
-        } else {
-            uint8_t* result_buf = FX_Alloc(uint8_t, dest_size);
-            FX_DWORD result_pos = 0;
-            for (int32_t i = 0; i < result_tmp_bufs.GetSize(); i++) {
-                uint8_t* tmp_buf = result_tmp_bufs[i];
-                FX_DWORD tmp_buf_size = buf_size;
-                if (i == result_tmp_bufs.GetSize() - 1) {
-                    tmp_buf_size = last_buf_size;
-                }
-                FXSYS_memcpy(result_buf + result_pos, tmp_buf, tmp_buf_size);
-                result_pos += tmp_buf_size;
-                FX_Free(result_tmp_bufs[i]);
-            }
-            dest_buf = result_buf;
-        }
-    }
-    FPDFAPI_FlateEnd(context);
-    return;
+      uint8_t* result_buf = FX_Alloc(uint8_t, dest_size);
+      FX_DWORD result_pos = 0;
+      for (int32_t i = 0; i < result_tmp_bufs.GetSize(); i++) {
+        uint8_t* tmp_buf = result_tmp_bufs[i];
+        FX_DWORD tmp_buf_size = buf_size;
+        if (i == result_tmp_bufs.GetSize() - 1) {
+          tmp_buf_size = last_buf_size;
+        }
+        FXSYS_memcpy(result_buf + result_pos, tmp_buf, tmp_buf_size);
+        result_pos += tmp_buf_size;
+        FX_Free(result_tmp_bufs[i]);
+      }
+      dest_buf = result_buf;
+    }
+  }
+  FPDFAPI_FlateEnd(context);
+  return;
 
 fail:
-    FX_Free(guess_buf);
-    dest_buf = nullptr;
-    dest_size = 0;
-    return;
-}
-ICodec_ScanlineDecoder* CCodec_FlateModule::CreateDecoder(const uint8_t* src_buf, FX_DWORD src_size, int width, int height,
-        int nComps, int bpc, int predictor, int Colors, int BitsPerComponent, int Columns)
-{
-    CCodec_FlateScanlineDecoder* pDecoder = new CCodec_FlateScanlineDecoder;
-    pDecoder->Create(src_buf, src_size, width, height, nComps, bpc, predictor, Colors, BitsPerComponent, Columns);
-    return pDecoder;
-}
-FX_DWORD CCodec_FlateModule::FlateOrLZWDecode(FX_BOOL bLZW, const uint8_t* src_buf, FX_DWORD src_size, FX_BOOL bEarlyChange,
-        int predictor, int Colors, int BitsPerComponent, int Columns,
-        FX_DWORD estimated_size, uint8_t*& dest_buf, FX_DWORD& dest_size)
-{
-    dest_buf = NULL;
-    FX_DWORD offset = 0;
-    int predictor_type = 0;
-    if (predictor) {
-        if (predictor >= 10) {
-            predictor_type = 2;
-        } else if (predictor == 2) {
-            predictor_type = 1;
-        }
-    }
-    if (bLZW) {
-        {
-            nonstd::unique_ptr<CLZWDecoder> decoder(new CLZWDecoder);
-            dest_size = (FX_DWORD) - 1;
-            offset = src_size;
-            int err = decoder->Decode(NULL, dest_size, src_buf, offset,
-                                      bEarlyChange);
-            if (err || dest_size == 0 || dest_size + 1 < dest_size) {
-                return -1;
-            }
-        }
-        {
-            nonstd::unique_ptr<CLZWDecoder> decoder(new CLZWDecoder);
-            dest_buf = FX_Alloc( uint8_t, dest_size + 1);
-            dest_buf[dest_size] = '\0';
-            decoder->Decode(dest_buf, dest_size, src_buf, offset, bEarlyChange);
-        }
-    } else {
-        FlateUncompress(src_buf, src_size, estimated_size, dest_buf, dest_size, offset);
-    }
-    if (predictor_type == 0) {
-        return offset;
-    }
-    FX_BOOL ret = TRUE;
-    if (predictor_type == 2) {
-        ret = PNG_Predictor(dest_buf, dest_size, Colors, BitsPerComponent,
-                            Columns);
-    } else if (predictor_type == 1) {
-        ret = TIFF_Predictor(dest_buf, dest_size, Colors, BitsPerComponent,
-                             Columns);
-    }
-    return ret ? offset : -1;
-}
-FX_BOOL CCodec_FlateModule::Encode(const uint8_t* src_buf, FX_DWORD src_size,
-                                   int predictor, int Colors, int BitsPerComponent, int Columns,
-                                   uint8_t*& dest_buf, FX_DWORD& dest_size)
-{
-    if (predictor != 2 && predictor < 10) {
-        return Encode(src_buf, src_size, dest_buf, dest_size);
-    }
-    uint8_t* pSrcBuf = NULL;
-    pSrcBuf = FX_Alloc(uint8_t, src_size);
-    FXSYS_memcpy(pSrcBuf, src_buf, src_size);
-    FX_BOOL ret = TRUE;
-    if (predictor == 2) {
-        ret = TIFF_PredictorEncode(pSrcBuf, src_size, Colors, BitsPerComponent,
-                                   Columns);
-    } else if (predictor >= 10) {
-        ret = PNG_PredictorEncode(pSrcBuf, src_size, predictor, Colors,
-                                  BitsPerComponent, Columns);
-    }
-    if (ret)
-        ret = Encode(pSrcBuf, src_size, dest_buf, dest_size);
-    FX_Free(pSrcBuf);
-    return ret;
-}
-FX_BOOL CCodec_FlateModule::Encode(const uint8_t* src_buf, FX_DWORD src_size, uint8_t*& dest_buf, FX_DWORD& dest_size)
-{
-    dest_size = src_size + src_size / 1000 + 12;
-    dest_buf = FX_Alloc( uint8_t, dest_size);
-    unsigned long temp_size = dest_size;
-    FPDFAPI_FlateCompress(dest_buf, &temp_size, src_buf, src_size);
-    dest_size = (FX_DWORD)temp_size;
-    return TRUE;
-}
+  FX_Free(guess_buf);
+  dest_buf = nullptr;
+  dest_size = 0;
+  return;
+}
+ICodec_ScanlineDecoder* CCodec_FlateModule::CreateDecoder(
+    const uint8_t* src_buf,
+    FX_DWORD src_size,
+    int width,
+    int height,
+    int nComps,
+    int bpc,
+    int predictor,
+    int Colors,
+    int BitsPerComponent,
+    int Columns) {
+  CCodec_FlateScanlineDecoder* pDecoder = new CCodec_FlateScanlineDecoder;
+  pDecoder->Create(src_buf, src_size, width, height, nComps, bpc, predictor,
+                   Colors, BitsPerComponent, Columns);
+  return pDecoder;
+}
+FX_DWORD CCodec_FlateModule::FlateOrLZWDecode(FX_BOOL bLZW,
+                                              const uint8_t* src_buf,
+                                              FX_DWORD src_size,
+                                              FX_BOOL bEarlyChange,
+                                              int predictor,
+                                              int Colors,
+                                              int BitsPerComponent,
+                                              int Columns,
+                                              FX_DWORD estimated_size,
+                                              uint8_t*& dest_buf,
+                                              FX_DWORD& dest_size) {
+  dest_buf = NULL;
+  FX_DWORD offset = 0;
+  int predictor_type = 0;
+  if (predictor) {
+    if (predictor >= 10) {
+      predictor_type = 2;
+    } else if (predictor == 2) {
+      predictor_type = 1;
+    }
+  }
+  if (bLZW) {
+    {
+      nonstd::unique_ptr<CLZWDecoder> decoder(new CLZWDecoder);
+      dest_size = (FX_DWORD)-1;
+      offset = src_size;
+      int err = decoder->Decode(NULL, dest_size, src_buf, offset, bEarlyChange);
+      if (err || dest_size == 0 || dest_size + 1 < dest_size) {
+        return -1;
+      }
+    }
+    {
+      nonstd::unique_ptr<CLZWDecoder> decoder(new CLZWDecoder);
+      dest_buf = FX_Alloc(uint8_t, dest_size + 1);
+      dest_buf[dest_size] = '\0';
+      decoder->Decode(dest_buf, dest_size, src_buf, offset, bEarlyChange);
+    }
+  } else {
+    FlateUncompress(src_buf, src_size, estimated_size, dest_buf, dest_size,
+                    offset);
+  }
+  if (predictor_type == 0) {
+    return offset;
+  }
+  FX_BOOL ret = TRUE;
+  if (predictor_type == 2) {
+    ret = PNG_Predictor(dest_buf, dest_size, Colors, BitsPerComponent, Columns);
+  } else if (predictor_type == 1) {
+    ret =
+        TIFF_Predictor(dest_buf, dest_size, Colors, BitsPerComponent, Columns);
+  }
+  return ret ? offset : -1;
+}
+FX_BOOL CCodec_FlateModule::Encode(const uint8_t* src_buf,
+                                   FX_DWORD src_size,
+                                   int predictor,
+                                   int Colors,
+                                   int BitsPerComponent,
+                                   int Columns,
+                                   uint8_t*& dest_buf,
+                                   FX_DWORD& dest_size) {
+  if (predictor != 2 && predictor < 10) {
+    return Encode(src_buf, src_size, dest_buf, dest_size);
+  }
+  uint8_t* pSrcBuf = NULL;
+  pSrcBuf = FX_Alloc(uint8_t, src_size);
+  FXSYS_memcpy(pSrcBuf, src_buf, src_size);
+  FX_BOOL ret = TRUE;
+  if (predictor == 2) {
+    ret = TIFF_PredictorEncode(pSrcBuf, src_size, Colors, BitsPerComponent,
+                               Columns);
+  } else if (predictor >= 10) {
+    ret = PNG_PredictorEncode(pSrcBuf, src_size, predictor, Colors,
+                              BitsPerComponent, Columns);
+  }
+  if (ret)
+    ret = Encode(pSrcBuf, src_size, dest_buf, dest_size);
+  FX_Free(pSrcBuf);
+  return ret;
+}
+FX_BOOL CCodec_FlateModule::Encode(const uint8_t* src_buf,
+                                   FX_DWORD src_size,
+                                   uint8_t*& dest_buf,
+                                   FX_DWORD& dest_size) {
+  dest_size = src_size + src_size / 1000 + 12;
+  dest_buf = FX_Alloc(uint8_t, dest_size);
+  unsigned long temp_size = dest_size;
+  FPDFAPI_FlateCompress(dest_buf, &temp_size, src_buf, src_size);
+  dest_size = (FX_DWORD)temp_size;
+  return TRUE;
+}