diff --git a/core/fxcodec/BUILD.gn b/core/fxcodec/BUILD.gn
index 3543360..479a7f5 100644
--- a/core/fxcodec/BUILD.gn
+++ b/core/fxcodec/BUILD.gn
@@ -27,6 +27,7 @@
     "codec/ccodec_scanlinedecoder.h",
     "codec/cfx_codec_memory.cpp",
     "codec/cfx_codec_memory.h",
+    "codec/cjpx_decoder.cpp",
     "codec/cjpx_decoder.h",
     "codec/codec_int.h",
     "codec/codec_module_iface.h",
diff --git a/core/fxcodec/codec/ccodec_jpxmodule.cpp b/core/fxcodec/codec/ccodec_jpxmodule.cpp
index 004e298..1df09d0 100644
--- a/core/fxcodec/codec/ccodec_jpxmodule.cpp
+++ b/core/fxcodec/codec/ccodec_jpxmodule.cpp
@@ -6,649 +6,8 @@
 
 #include "core/fxcodec/codec/ccodec_jpxmodule.h"
 
-#include <algorithm>
-#include <limits>
-#include <memory>
-#include <type_traits>
-#include <utility>
-#include <vector>
-
-#include "core/fpdfapi/page/cpdf_colorspace.h"
 #include "core/fxcodec/codec/cjpx_decoder.h"
-#include "core/fxcrt/fx_safe_types.h"
-#include "third_party/base/optional.h"
 #include "third_party/base/ptr_util.h"
-#include "third_party/base/stl_util.h"
-
-#ifndef USE_SYSTEM_LIBOPENJPEG2
-#include "third_party/libopenjpeg20/openjpeg.h"
-#include "third_party/libopenjpeg20/opj_malloc.h"
-#endif
-
-namespace {
-
-// Used with std::unique_ptr to call opj_image_data_free on raw memory.
-struct OpjImageDataDeleter {
-  inline void operator()(void* ptr) const { opj_image_data_free(ptr); }
-};
-
-using ScopedOpjImageData = std::unique_ptr<int, OpjImageDataDeleter>;
-
-struct OpjImageRgbData {
-  ScopedOpjImageData r;
-  ScopedOpjImageData g;
-  ScopedOpjImageData b;
-};
-
-void fx_ignore_callback(const char* msg, void* client_data) {}
-
-opj_stream_t* fx_opj_stream_create_memory_stream(DecodeData* data) {
-  if (!data || !data->src_data || data->src_size <= 0)
-    return nullptr;
-
-  opj_stream_t* stream = opj_stream_create(OPJ_J2K_STREAM_CHUNK_SIZE,
-                                           /*p_is_input=*/OPJ_TRUE);
-  if (!stream)
-    return nullptr;
-
-  opj_stream_set_user_data(stream, data, nullptr);
-  opj_stream_set_user_data_length(stream, data->src_size);
-  opj_stream_set_read_function(stream, opj_read_from_memory);
-  opj_stream_set_skip_function(stream, opj_skip_from_memory);
-  opj_stream_set_seek_function(stream, opj_seek_from_memory);
-  return stream;
-}
-
-Optional<OpjImageRgbData> alloc_rgb(size_t size) {
-  OpjImageRgbData data;
-  data.r.reset(static_cast<int*>(opj_image_data_alloc(size)));
-  if (!data.r)
-    return {};
-
-  data.g.reset(static_cast<int*>(opj_image_data_alloc(size)));
-  if (!data.g)
-    return {};
-
-  data.b.reset(static_cast<int*>(opj_image_data_alloc(size)));
-  if (!data.b)
-    return {};
-
-  return data;
-}
-
-void sycc_to_rgb(int offset,
-                 int upb,
-                 int y,
-                 int cb,
-                 int cr,
-                 int* out_r,
-                 int* out_g,
-                 int* out_b) {
-  cb -= offset;
-  cr -= offset;
-  *out_r = pdfium::clamp(y + static_cast<int>(1.402 * cr), 0, upb);
-  *out_g = pdfium::clamp(y - static_cast<int>(0.344 * cb + 0.714 * cr), 0, upb);
-  *out_b = pdfium::clamp(y + static_cast<int>(1.772 * cb), 0, upb);
-}
-
-void sycc444_to_rgb(opj_image_t* img) {
-  int prec = img->comps[0].prec;
-  // If we shift 31 we're going to go negative, then things go bad.
-  if (prec > 30)
-    return;
-  int offset = 1 << (prec - 1);
-  int upb = (1 << prec) - 1;
-  OPJ_UINT32 maxw =
-      std::min({img->comps[0].w, img->comps[1].w, img->comps[2].w});
-  OPJ_UINT32 maxh =
-      std::min({img->comps[0].h, img->comps[1].h, img->comps[2].h});
-  FX_SAFE_SIZE_T max_size = maxw;
-  max_size *= maxh;
-  max_size *= sizeof(int);
-  if (!max_size.IsValid())
-    return;
-
-  const int* y = img->comps[0].data;
-  const int* cb = img->comps[1].data;
-  const int* cr = img->comps[2].data;
-  if (!y || !cb || !cr)
-    return;
-
-  Optional<OpjImageRgbData> data = alloc_rgb(max_size.ValueOrDie());
-  if (!data.has_value())
-    return;
-
-  int* r = data.value().r.get();
-  int* g = data.value().g.get();
-  int* b = data.value().b.get();
-  max_size /= sizeof(int);
-  for (size_t i = 0; i < max_size.ValueOrDie(); ++i)
-    sycc_to_rgb(offset, upb, *y++, *cb++, *cr++, r++, g++, b++);
-
-  opj_image_data_free(img->comps[0].data);
-  opj_image_data_free(img->comps[1].data);
-  opj_image_data_free(img->comps[2].data);
-  img->comps[0].data = data.value().r.release();
-  img->comps[1].data = data.value().g.release();
-  img->comps[2].data = data.value().b.release();
-}
-
-bool sycc420_422_size_is_valid(opj_image_t* img) {
-  return img && img->comps[0].w != std::numeric_limits<OPJ_UINT32>::max() &&
-         (img->comps[0].w + 1) / 2 == img->comps[1].w &&
-         img->comps[1].w == img->comps[2].w &&
-         img->comps[1].h == img->comps[2].h;
-}
-
-bool sycc420_size_is_valid(opj_image_t* img) {
-  return sycc420_422_size_is_valid(img) &&
-         img->comps[0].h != std::numeric_limits<OPJ_UINT32>::max() &&
-         (img->comps[0].h + 1) / 2 == img->comps[1].h;
-}
-
-bool sycc422_size_is_valid(opj_image_t* img) {
-  return sycc420_422_size_is_valid(img) && img->comps[0].h == img->comps[1].h;
-}
-
-void sycc422_to_rgb(opj_image_t* img) {
-  if (!sycc422_size_is_valid(img))
-    return;
-
-  int prec = img->comps[0].prec;
-  if (prec <= 0 || prec >= 32)
-    return;
-
-  int offset = 1 << (prec - 1);
-  int upb = (1 << prec) - 1;
-  OPJ_UINT32 maxw = img->comps[0].w;
-  OPJ_UINT32 maxh = img->comps[0].h;
-  FX_SAFE_SIZE_T max_size = maxw;
-  max_size *= maxh;
-  max_size *= sizeof(int);
-  if (!max_size.IsValid())
-    return;
-
-  const int* y = img->comps[0].data;
-  const int* cb = img->comps[1].data;
-  const int* cr = img->comps[2].data;
-  if (!y || !cb || !cr)
-    return;
-
-  Optional<OpjImageRgbData> data = alloc_rgb(max_size.ValueOrDie());
-  if (!data.has_value())
-    return;
-
-  int* r = data.value().r.get();
-  int* g = data.value().g.get();
-  int* b = data.value().b.get();
-  for (uint32_t i = 0; i < maxh; ++i) {
-    OPJ_UINT32 j;
-    for (j = 0; j < (maxw & ~static_cast<OPJ_UINT32>(1)); j += 2) {
-      sycc_to_rgb(offset, upb, *y++, *cb, *cr, r++, g++, b++);
-      sycc_to_rgb(offset, upb, *y++, *cb++, *cr++, r++, g++, b++);
-    }
-    if (j < maxw) {
-      sycc_to_rgb(offset, upb, *y++, *cb++, *cr++, r++, g++, b++);
-    }
-  }
-
-  opj_image_data_free(img->comps[0].data);
-  opj_image_data_free(img->comps[1].data);
-  opj_image_data_free(img->comps[2].data);
-  img->comps[0].data = data.value().r.release();
-  img->comps[1].data = data.value().g.release();
-  img->comps[2].data = data.value().b.release();
-  img->comps[1].w = maxw;
-  img->comps[1].h = maxh;
-  img->comps[2].w = maxw;
-  img->comps[2].h = maxh;
-  img->comps[1].dx = img->comps[0].dx;
-  img->comps[2].dx = img->comps[0].dx;
-  img->comps[1].dy = img->comps[0].dy;
-  img->comps[2].dy = img->comps[0].dy;
-}
-
-bool sycc420_must_extend_cbcr(OPJ_UINT32 y, OPJ_UINT32 cbcr) {
-  return (y & 1) && (cbcr == y / 2);
-}
-
-bool is_sycc420(const opj_image_t* img) {
-  return img->comps[0].dx == 1 && img->comps[0].dy == 1 &&
-         img->comps[1].dx == 2 && img->comps[1].dy == 2 &&
-         img->comps[2].dx == 2 && img->comps[2].dy == 2;
-}
-
-bool is_sycc422(const opj_image_t* img) {
-  return img->comps[0].dx == 1 && img->comps[0].dy == 1 &&
-         img->comps[1].dx == 2 && img->comps[1].dy == 1 &&
-         img->comps[2].dx == 2 && img->comps[2].dy == 1;
-}
-
-bool is_sycc444(const opj_image_t* img) {
-  return img->comps[0].dx == 1 && img->comps[0].dy == 1 &&
-         img->comps[1].dx == 1 && img->comps[1].dy == 1 &&
-         img->comps[2].dx == 1 && img->comps[2].dy == 1;
-}
-
-void color_sycc_to_rgb(opj_image_t* img) {
-  if (img->numcomps < 3) {
-    img->color_space = OPJ_CLRSPC_GRAY;
-    return;
-  }
-  if (is_sycc420(img))
-    sycc420_to_rgb(img);
-  else if (is_sycc422(img))
-    sycc422_to_rgb(img);
-  else if (is_sycc444(img))
-    sycc444_to_rgb(img);
-  else
-    return;
-
-  img->color_space = OPJ_CLRSPC_SRGB;
-}
-
-}  // namespace
-
-OPJ_SIZE_T opj_read_from_memory(void* p_buffer,
-                                OPJ_SIZE_T nb_bytes,
-                                void* p_user_data) {
-  DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
-  if (!srcData || !srcData->src_data || srcData->src_size == 0)
-    return static_cast<OPJ_SIZE_T>(-1);
-
-  // Reads at EOF return an error code.
-  if (srcData->offset >= srcData->src_size)
-    return static_cast<OPJ_SIZE_T>(-1);
-
-  OPJ_SIZE_T bufferLength = srcData->src_size - srcData->offset;
-  OPJ_SIZE_T readlength = nb_bytes < bufferLength ? nb_bytes : bufferLength;
-  memcpy(p_buffer, &srcData->src_data[srcData->offset], readlength);
-  srcData->offset += readlength;
-  return readlength;
-}
-
-OPJ_OFF_T opj_skip_from_memory(OPJ_OFF_T nb_bytes, void* p_user_data) {
-  DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
-  if (!srcData || !srcData->src_data || srcData->src_size == 0)
-    return static_cast<OPJ_OFF_T>(-1);
-
-  // Offsets are signed and may indicate a negative skip. Do not support this
-  // because of the strange return convention where either bytes skipped or
-  // -1 is returned. Following that convention, a successful relative seek of
-  // -1 bytes would be required to to give the same result as the error case.
-  if (nb_bytes < 0)
-    return static_cast<OPJ_OFF_T>(-1);
-
-  auto unsigned_nb_bytes =
-      static_cast<std::make_unsigned<OPJ_OFF_T>::type>(nb_bytes);
-  // Additionally, the offset may take us beyond the range of a size_t (e.g.
-  // 32-bit platforms). If so, just clamp at EOF.
-  if (unsigned_nb_bytes >
-      std::numeric_limits<OPJ_SIZE_T>::max() - srcData->offset) {
-    srcData->offset = srcData->src_size;
-  } else {
-    OPJ_SIZE_T checked_nb_bytes = static_cast<OPJ_SIZE_T>(unsigned_nb_bytes);
-    // Otherwise, mimic fseek() semantics to always succeed, even past EOF,
-    // clamping at EOF.  We can get away with this since we don't actually
-    // provide negative relative skips from beyond EOF back to inside the
-    // data, which would be the only reason to need to know exactly how far
-    // beyond EOF we are.
-    srcData->offset =
-        std::min(srcData->offset + checked_nb_bytes, srcData->src_size);
-  }
-  return nb_bytes;
-}
-
-OPJ_BOOL opj_seek_from_memory(OPJ_OFF_T nb_bytes, void* p_user_data) {
-  DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
-  if (!srcData || !srcData->src_data || srcData->src_size == 0)
-    return OPJ_FALSE;
-
-  // Offsets are signed and may indicate a negative position, which would
-  // be before the start of the file. Do not support this.
-  if (nb_bytes < 0)
-    return OPJ_FALSE;
-
-  auto unsigned_nb_bytes =
-      static_cast<std::make_unsigned<OPJ_OFF_T>::type>(nb_bytes);
-  // Additionally, the offset may take us beyond the range of a size_t (e.g.
-  // 32-bit platforms). If so, just clamp at EOF.
-  if (unsigned_nb_bytes > std::numeric_limits<OPJ_SIZE_T>::max()) {
-    srcData->offset = srcData->src_size;
-  } else {
-    OPJ_SIZE_T checked_nb_bytes = static_cast<OPJ_SIZE_T>(nb_bytes);
-    // Otherwise, mimic fseek() semantics to always succeed, even past EOF,
-    // again clamping at EOF.
-    srcData->offset = std::min(checked_nb_bytes, srcData->src_size);
-  }
-  return OPJ_TRUE;
-}
-
-void sycc420_to_rgb(opj_image_t* img) {
-  if (!sycc420_size_is_valid(img))
-    return;
-
-  OPJ_UINT32 prec = img->comps[0].prec;
-  if (!prec)
-    return;
-
-  OPJ_UINT32 offset = 1 << (prec - 1);
-  OPJ_UINT32 upb = (1 << prec) - 1;
-  OPJ_UINT32 yw = img->comps[0].w;
-  OPJ_UINT32 yh = img->comps[0].h;
-  OPJ_UINT32 cbw = img->comps[1].w;
-  OPJ_UINT32 cbh = img->comps[1].h;
-  OPJ_UINT32 crw = img->comps[2].w;
-  bool extw = sycc420_must_extend_cbcr(yw, cbw);
-  bool exth = sycc420_must_extend_cbcr(yh, cbh);
-  FX_SAFE_UINT32 safe_size = yw;
-  safe_size *= yh;
-  safe_size *= sizeof(int);
-  if (!safe_size.IsValid())
-    return;
-
-  const int* y = img->comps[0].data;
-  const int* cb = img->comps[1].data;
-  const int* cr = img->comps[2].data;
-  if (!y || !cb || !cr)
-    return;
-
-  Optional<OpjImageRgbData> data = alloc_rgb(safe_size.ValueOrDie());
-  if (!data.has_value())
-    return;
-
-  int* r = data.value().r.get();
-  int* g = data.value().g.get();
-  int* b = data.value().b.get();
-  const int* ny = nullptr;
-  int* nr = nullptr;
-  int* ng = nullptr;
-  int* nb = nullptr;
-  OPJ_UINT32 i = 0;
-  OPJ_UINT32 j = 0;
-  for (i = 0; i < (yh & ~(OPJ_UINT32)1); i += 2) {
-    ny = y + yw;
-    nr = r + yw;
-    ng = g + yw;
-    nb = b + yw;
-    for (j = 0; j < (yw & ~(OPJ_UINT32)1); j += 2) {
-      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
-      ++y;
-      ++r;
-      ++g;
-      ++b;
-      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
-      ++y;
-      ++r;
-      ++g;
-      ++b;
-      sycc_to_rgb(offset, upb, *ny, *cb, *cr, nr, ng, nb);
-      ++ny;
-      ++nr;
-      ++ng;
-      ++nb;
-      sycc_to_rgb(offset, upb, *ny, *cb, *cr, nr, ng, nb);
-      ++ny;
-      ++nr;
-      ++ng;
-      ++nb;
-      ++cb;
-      ++cr;
-    }
-    if (j < yw) {
-      if (extw) {
-        --cb;
-        --cr;
-      }
-      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
-      ++y;
-      ++r;
-      ++g;
-      ++b;
-      sycc_to_rgb(offset, upb, *ny, *cb, *cr, nr, ng, nb);
-      ++ny;
-      ++nr;
-      ++ng;
-      ++nb;
-      ++cb;
-      ++cr;
-    }
-    y += yw;
-    r += yw;
-    g += yw;
-    b += yw;
-  }
-  if (i < yh) {
-    if (exth) {
-      cb -= cbw;
-      cr -= crw;
-    }
-    for (j = 0; j < (yw & ~(OPJ_UINT32)1); j += 2) {
-      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
-      ++y;
-      ++r;
-      ++g;
-      ++b;
-      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
-      ++y;
-      ++r;
-      ++g;
-      ++b;
-      ++cb;
-      ++cr;
-    }
-    if (j < yw) {
-      if (extw) {
-        --cb;
-        --cr;
-      }
-      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
-    }
-  }
-
-  opj_image_data_free(img->comps[0].data);
-  opj_image_data_free(img->comps[1].data);
-  opj_image_data_free(img->comps[2].data);
-  img->comps[0].data = data.value().r.release();
-  img->comps[1].data = data.value().g.release();
-  img->comps[2].data = data.value().b.release();
-  img->comps[1].w = yw;
-  img->comps[1].h = yh;
-  img->comps[2].w = yw;
-  img->comps[2].h = yh;
-  img->comps[1].dx = img->comps[0].dx;
-  img->comps[2].dx = img->comps[0].dx;
-  img->comps[1].dy = img->comps[0].dy;
-  img->comps[2].dy = img->comps[0].dy;
-}
-
-CJPX_Decoder::CJPX_Decoder(const RetainPtr<CPDF_ColorSpace>& cs)
-    : m_Image(nullptr),
-      m_Codec(nullptr),
-      m_DecodeData(nullptr),
-      m_Stream(nullptr),
-      m_ColorSpace(cs) {}
-
-CJPX_Decoder::~CJPX_Decoder() {
-  if (m_Codec)
-    opj_destroy_codec(m_Codec.Release());
-  if (m_Stream)
-    opj_stream_destroy(m_Stream.Release());
-  if (m_Image)
-    opj_image_destroy(m_Image.Release());
-}
-
-bool CJPX_Decoder::Init(pdfium::span<const uint8_t> src_data) {
-  static const unsigned char szJP2Header[] = {
-      0x00, 0x00, 0x00, 0x0c, 0x6a, 0x50, 0x20, 0x20, 0x0d, 0x0a, 0x87, 0x0a};
-  if (src_data.empty() || src_data.size() < sizeof(szJP2Header))
-    return false;
-
-  m_Image = nullptr;
-  m_SrcData = src_data;
-  m_DecodeData =
-      pdfium::MakeUnique<DecodeData>(src_data.data(), src_data.size());
-  m_Stream = fx_opj_stream_create_memory_stream(m_DecodeData.get());
-  if (!m_Stream)
-    return false;
-
-  opj_set_default_decoder_parameters(&m_Parameters);
-  m_Parameters.decod_format = 0;
-  m_Parameters.cod_format = 3;
-  if (memcmp(m_SrcData.data(), szJP2Header, sizeof(szJP2Header)) == 0) {
-    m_Codec = opj_create_decompress(OPJ_CODEC_JP2);
-    m_Parameters.decod_format = 1;
-  } else {
-    m_Codec = opj_create_decompress(OPJ_CODEC_J2K);
-  }
-  if (!m_Codec)
-    return false;
-
-  if (m_ColorSpace && m_ColorSpace->GetFamily() == PDFCS_INDEXED)
-    m_Parameters.flags |= OPJ_DPARAMETERS_IGNORE_PCLR_CMAP_CDEF_FLAG;
-  opj_set_info_handler(m_Codec.Get(), fx_ignore_callback, nullptr);
-  opj_set_warning_handler(m_Codec.Get(), fx_ignore_callback, nullptr);
-  opj_set_error_handler(m_Codec.Get(), fx_ignore_callback, nullptr);
-  if (!opj_setup_decoder(m_Codec.Get(), &m_Parameters))
-    return false;
-
-  m_Image = nullptr;
-  opj_image_t* pTempImage = nullptr;
-  if (!opj_read_header(m_Stream.Get(), m_Codec.Get(), &pTempImage))
-    return false;
-
-  m_Image = pTempImage;
-#ifndef USE_SYSTEM_LIBOPENJPEG2
-  m_Image->pdfium_use_colorspace = !!m_ColorSpace;
-#endif
-  return true;
-}
-
-bool CJPX_Decoder::StartDecode() {
-  if (!m_Parameters.nb_tile_to_decode) {
-    if (!opj_set_decode_area(m_Codec.Get(), m_Image.Get(), m_Parameters.DA_x0,
-                             m_Parameters.DA_y0, m_Parameters.DA_x1,
-                             m_Parameters.DA_y1)) {
-      opj_image_destroy(m_Image.Release());
-      return false;
-    }
-    if (!(opj_decode(m_Codec.Get(), m_Stream.Get(), m_Image.Get()) &&
-          opj_end_decompress(m_Codec.Get(), m_Stream.Get()))) {
-      opj_image_destroy(m_Image.Release());
-      return false;
-    }
-  } else if (!opj_get_decoded_tile(m_Codec.Get(), m_Stream.Get(), m_Image.Get(),
-                                   m_Parameters.tile_index)) {
-    return false;
-  }
-
-  opj_stream_destroy(m_Stream.Release());
-  if (m_Image->color_space != OPJ_CLRSPC_SYCC && m_Image->numcomps == 3 &&
-      m_Image->comps[0].dx == m_Image->comps[0].dy &&
-      m_Image->comps[1].dx != 1) {
-    m_Image->color_space = OPJ_CLRSPC_SYCC;
-  } else if (m_Image->numcomps <= 2) {
-    m_Image->color_space = OPJ_CLRSPC_GRAY;
-  }
-  if (m_Image->color_space == OPJ_CLRSPC_SYCC)
-    color_sycc_to_rgb(m_Image.Get());
-
-  if (m_Image->icc_profile_buf) {
-    // TODO(palmer): Using |opj_free| here resolves the crash described in
-    // https://crbug.com/737033, but ultimately we need to harmonize the
-    // memory allocation strategy across OpenJPEG and its PDFium callers.
-#ifndef USE_SYSTEM_LIBOPENJPEG2
-    opj_free(m_Image->icc_profile_buf);
-#else
-    free(m_Image->icc_profile_buf);
-#endif
-    m_Image->icc_profile_buf = nullptr;
-    m_Image->icc_profile_len = 0;
-  }
-  return true;
-}
-
-void CJPX_Decoder::GetInfo(uint32_t* width,
-                           uint32_t* height,
-                           uint32_t* components) {
-  *width = m_Image->x1;
-  *height = m_Image->y1;
-  *components = m_Image->numcomps;
-}
-
-bool CJPX_Decoder::Decode(uint8_t* dest_buf,
-                          uint32_t pitch,
-                          const std::vector<uint8_t>& offsets) {
-  if (m_Image->comps[0].w != m_Image->x1 || m_Image->comps[0].h != m_Image->y1)
-    return false;
-
-  if (pitch<(m_Image->comps[0].w * 8 * m_Image->numcomps + 31)>> 5 << 2) {
-    return false;
-  }
-
-  memset(dest_buf, 0xff, m_Image->y1 * pitch);
-  std::vector<uint8_t*> channel_bufs(m_Image->numcomps);
-  std::vector<int> adjust_comps(m_Image->numcomps);
-  for (uint32_t i = 0; i < m_Image->numcomps; i++) {
-    channel_bufs[i] = dest_buf + offsets[i];
-    adjust_comps[i] = m_Image->comps[i].prec - 8;
-    if (i > 0) {
-      if (m_Image->comps[i].dx != m_Image->comps[i - 1].dx ||
-          m_Image->comps[i].dy != m_Image->comps[i - 1].dy ||
-          m_Image->comps[i].prec != m_Image->comps[i - 1].prec) {
-        return false;
-      }
-    }
-  }
-  uint32_t width = m_Image->comps[0].w;
-  uint32_t height = m_Image->comps[0].h;
-  for (uint32_t channel = 0; channel < m_Image->numcomps; ++channel) {
-    uint8_t* pChannel = channel_bufs[channel];
-    if (adjust_comps[channel] < 0) {
-      for (uint32_t row = 0; row < height; ++row) {
-        uint8_t* pScanline = pChannel + row * pitch;
-        for (uint32_t col = 0; col < width; ++col) {
-          uint8_t* pPixel = pScanline + col * m_Image->numcomps;
-          if (!m_Image->comps[channel].data)
-            continue;
-
-          int src = m_Image->comps[channel].data[row * width + col];
-          src += m_Image->comps[channel].sgnd
-                     ? 1 << (m_Image->comps[channel].prec - 1)
-                     : 0;
-          if (adjust_comps[channel] > 0) {
-            *pPixel = 0;
-          } else {
-            *pPixel = static_cast<uint8_t>(src << -adjust_comps[channel]);
-          }
-        }
-      }
-    } else {
-      for (uint32_t row = 0; row < height; ++row) {
-        uint8_t* pScanline = pChannel + row * pitch;
-        for (uint32_t col = 0; col < width; ++col) {
-          uint8_t* pPixel = pScanline + col * m_Image->numcomps;
-          if (!m_Image->comps[channel].data)
-            continue;
-
-          int src = m_Image->comps[channel].data[row * width + col];
-          src += m_Image->comps[channel].sgnd
-                     ? 1 << (m_Image->comps[channel].prec - 1)
-                     : 0;
-          if (adjust_comps[channel] - 1 < 0) {
-            *pPixel = static_cast<uint8_t>((src >> adjust_comps[channel]));
-          } else {
-            int tmpPixel = (src >> adjust_comps[channel]) +
-                           ((src >> (adjust_comps[channel] - 1)) % 2);
-            tmpPixel = pdfium::clamp(tmpPixel, 0, 255);
-            *pPixel = static_cast<uint8_t>(tmpPixel);
-          }
-        }
-      }
-    }
-  }
-  return true;
-}
 
 // static
 std::unique_ptr<CJPX_Decoder> CCodec_JpxModule::CreateDecoder(
diff --git a/core/fxcodec/codec/cjpx_decoder.cpp b/core/fxcodec/codec/cjpx_decoder.cpp
new file mode 100644
index 0000000..3614141
--- /dev/null
+++ b/core/fxcodec/codec/cjpx_decoder.cpp
@@ -0,0 +1,650 @@
+// Copyright 2019 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/cjpx_decoder.h"
+
+#include <algorithm>
+#include <limits>
+#include <memory>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#include "core/fpdfapi/page/cpdf_colorspace.h"
+#include "core/fxcrt/fx_safe_types.h"
+#include "third_party/base/optional.h"
+#include "third_party/base/ptr_util.h"
+#include "third_party/base/stl_util.h"
+
+#ifndef USE_SYSTEM_LIBOPENJPEG2
+#include "third_party/libopenjpeg20/openjpeg.h"
+#include "third_party/libopenjpeg20/opj_malloc.h"
+#endif
+
+namespace {
+
+// Used with std::unique_ptr to call opj_image_data_free on raw memory.
+struct OpjImageDataDeleter {
+  inline void operator()(void* ptr) const { opj_image_data_free(ptr); }
+};
+
+using ScopedOpjImageData = std::unique_ptr<int, OpjImageDataDeleter>;
+
+struct OpjImageRgbData {
+  ScopedOpjImageData r;
+  ScopedOpjImageData g;
+  ScopedOpjImageData b;
+};
+
+void fx_ignore_callback(const char* msg, void* client_data) {}
+
+opj_stream_t* fx_opj_stream_create_memory_stream(DecodeData* data) {
+  if (!data || !data->src_data || data->src_size <= 0)
+    return nullptr;
+
+  opj_stream_t* stream = opj_stream_create(OPJ_J2K_STREAM_CHUNK_SIZE,
+                                           /*p_is_input=*/OPJ_TRUE);
+  if (!stream)
+    return nullptr;
+
+  opj_stream_set_user_data(stream, data, nullptr);
+  opj_stream_set_user_data_length(stream, data->src_size);
+  opj_stream_set_read_function(stream, opj_read_from_memory);
+  opj_stream_set_skip_function(stream, opj_skip_from_memory);
+  opj_stream_set_seek_function(stream, opj_seek_from_memory);
+  return stream;
+}
+
+Optional<OpjImageRgbData> alloc_rgb(size_t size) {
+  OpjImageRgbData data;
+  data.r.reset(static_cast<int*>(opj_image_data_alloc(size)));
+  if (!data.r)
+    return {};
+
+  data.g.reset(static_cast<int*>(opj_image_data_alloc(size)));
+  if (!data.g)
+    return {};
+
+  data.b.reset(static_cast<int*>(opj_image_data_alloc(size)));
+  if (!data.b)
+    return {};
+
+  return data;
+}
+
+void sycc_to_rgb(int offset,
+                 int upb,
+                 int y,
+                 int cb,
+                 int cr,
+                 int* out_r,
+                 int* out_g,
+                 int* out_b) {
+  cb -= offset;
+  cr -= offset;
+  *out_r = pdfium::clamp(y + static_cast<int>(1.402 * cr), 0, upb);
+  *out_g = pdfium::clamp(y - static_cast<int>(0.344 * cb + 0.714 * cr), 0, upb);
+  *out_b = pdfium::clamp(y + static_cast<int>(1.772 * cb), 0, upb);
+}
+
+void sycc444_to_rgb(opj_image_t* img) {
+  int prec = img->comps[0].prec;
+  // If we shift 31 we're going to go negative, then things go bad.
+  if (prec > 30)
+    return;
+  int offset = 1 << (prec - 1);
+  int upb = (1 << prec) - 1;
+  OPJ_UINT32 maxw =
+      std::min({img->comps[0].w, img->comps[1].w, img->comps[2].w});
+  OPJ_UINT32 maxh =
+      std::min({img->comps[0].h, img->comps[1].h, img->comps[2].h});
+  FX_SAFE_SIZE_T max_size = maxw;
+  max_size *= maxh;
+  max_size *= sizeof(int);
+  if (!max_size.IsValid())
+    return;
+
+  const int* y = img->comps[0].data;
+  const int* cb = img->comps[1].data;
+  const int* cr = img->comps[2].data;
+  if (!y || !cb || !cr)
+    return;
+
+  Optional<OpjImageRgbData> data = alloc_rgb(max_size.ValueOrDie());
+  if (!data.has_value())
+    return;
+
+  int* r = data.value().r.get();
+  int* g = data.value().g.get();
+  int* b = data.value().b.get();
+  max_size /= sizeof(int);
+  for (size_t i = 0; i < max_size.ValueOrDie(); ++i)
+    sycc_to_rgb(offset, upb, *y++, *cb++, *cr++, r++, g++, b++);
+
+  opj_image_data_free(img->comps[0].data);
+  opj_image_data_free(img->comps[1].data);
+  opj_image_data_free(img->comps[2].data);
+  img->comps[0].data = data.value().r.release();
+  img->comps[1].data = data.value().g.release();
+  img->comps[2].data = data.value().b.release();
+}
+
+bool sycc420_422_size_is_valid(opj_image_t* img) {
+  return img && img->comps[0].w != std::numeric_limits<OPJ_UINT32>::max() &&
+         (img->comps[0].w + 1) / 2 == img->comps[1].w &&
+         img->comps[1].w == img->comps[2].w &&
+         img->comps[1].h == img->comps[2].h;
+}
+
+bool sycc420_size_is_valid(opj_image_t* img) {
+  return sycc420_422_size_is_valid(img) &&
+         img->comps[0].h != std::numeric_limits<OPJ_UINT32>::max() &&
+         (img->comps[0].h + 1) / 2 == img->comps[1].h;
+}
+
+bool sycc422_size_is_valid(opj_image_t* img) {
+  return sycc420_422_size_is_valid(img) && img->comps[0].h == img->comps[1].h;
+}
+
+void sycc422_to_rgb(opj_image_t* img) {
+  if (!sycc422_size_is_valid(img))
+    return;
+
+  int prec = img->comps[0].prec;
+  if (prec <= 0 || prec >= 32)
+    return;
+
+  int offset = 1 << (prec - 1);
+  int upb = (1 << prec) - 1;
+  OPJ_UINT32 maxw = img->comps[0].w;
+  OPJ_UINT32 maxh = img->comps[0].h;
+  FX_SAFE_SIZE_T max_size = maxw;
+  max_size *= maxh;
+  max_size *= sizeof(int);
+  if (!max_size.IsValid())
+    return;
+
+  const int* y = img->comps[0].data;
+  const int* cb = img->comps[1].data;
+  const int* cr = img->comps[2].data;
+  if (!y || !cb || !cr)
+    return;
+
+  Optional<OpjImageRgbData> data = alloc_rgb(max_size.ValueOrDie());
+  if (!data.has_value())
+    return;
+
+  int* r = data.value().r.get();
+  int* g = data.value().g.get();
+  int* b = data.value().b.get();
+  for (uint32_t i = 0; i < maxh; ++i) {
+    OPJ_UINT32 j;
+    for (j = 0; j < (maxw & ~static_cast<OPJ_UINT32>(1)); j += 2) {
+      sycc_to_rgb(offset, upb, *y++, *cb, *cr, r++, g++, b++);
+      sycc_to_rgb(offset, upb, *y++, *cb++, *cr++, r++, g++, b++);
+    }
+    if (j < maxw) {
+      sycc_to_rgb(offset, upb, *y++, *cb++, *cr++, r++, g++, b++);
+    }
+  }
+
+  opj_image_data_free(img->comps[0].data);
+  opj_image_data_free(img->comps[1].data);
+  opj_image_data_free(img->comps[2].data);
+  img->comps[0].data = data.value().r.release();
+  img->comps[1].data = data.value().g.release();
+  img->comps[2].data = data.value().b.release();
+  img->comps[1].w = maxw;
+  img->comps[1].h = maxh;
+  img->comps[2].w = maxw;
+  img->comps[2].h = maxh;
+  img->comps[1].dx = img->comps[0].dx;
+  img->comps[2].dx = img->comps[0].dx;
+  img->comps[1].dy = img->comps[0].dy;
+  img->comps[2].dy = img->comps[0].dy;
+}
+
+bool sycc420_must_extend_cbcr(OPJ_UINT32 y, OPJ_UINT32 cbcr) {
+  return (y & 1) && (cbcr == y / 2);
+}
+
+bool is_sycc420(const opj_image_t* img) {
+  return img->comps[0].dx == 1 && img->comps[0].dy == 1 &&
+         img->comps[1].dx == 2 && img->comps[1].dy == 2 &&
+         img->comps[2].dx == 2 && img->comps[2].dy == 2;
+}
+
+bool is_sycc422(const opj_image_t* img) {
+  return img->comps[0].dx == 1 && img->comps[0].dy == 1 &&
+         img->comps[1].dx == 2 && img->comps[1].dy == 1 &&
+         img->comps[2].dx == 2 && img->comps[2].dy == 1;
+}
+
+bool is_sycc444(const opj_image_t* img) {
+  return img->comps[0].dx == 1 && img->comps[0].dy == 1 &&
+         img->comps[1].dx == 1 && img->comps[1].dy == 1 &&
+         img->comps[2].dx == 1 && img->comps[2].dy == 1;
+}
+
+void color_sycc_to_rgb(opj_image_t* img) {
+  if (img->numcomps < 3) {
+    img->color_space = OPJ_CLRSPC_GRAY;
+    return;
+  }
+  if (is_sycc420(img))
+    sycc420_to_rgb(img);
+  else if (is_sycc422(img))
+    sycc422_to_rgb(img);
+  else if (is_sycc444(img))
+    sycc444_to_rgb(img);
+  else
+    return;
+
+  img->color_space = OPJ_CLRSPC_SRGB;
+}
+
+}  // namespace
+
+OPJ_SIZE_T opj_read_from_memory(void* p_buffer,
+                                OPJ_SIZE_T nb_bytes,
+                                void* p_user_data) {
+  DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
+  if (!srcData || !srcData->src_data || srcData->src_size == 0)
+    return static_cast<OPJ_SIZE_T>(-1);
+
+  // Reads at EOF return an error code.
+  if (srcData->offset >= srcData->src_size)
+    return static_cast<OPJ_SIZE_T>(-1);
+
+  OPJ_SIZE_T bufferLength = srcData->src_size - srcData->offset;
+  OPJ_SIZE_T readlength = nb_bytes < bufferLength ? nb_bytes : bufferLength;
+  memcpy(p_buffer, &srcData->src_data[srcData->offset], readlength);
+  srcData->offset += readlength;
+  return readlength;
+}
+
+OPJ_OFF_T opj_skip_from_memory(OPJ_OFF_T nb_bytes, void* p_user_data) {
+  DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
+  if (!srcData || !srcData->src_data || srcData->src_size == 0)
+    return static_cast<OPJ_OFF_T>(-1);
+
+  // Offsets are signed and may indicate a negative skip. Do not support this
+  // because of the strange return convention where either bytes skipped or
+  // -1 is returned. Following that convention, a successful relative seek of
+  // -1 bytes would be required to to give the same result as the error case.
+  if (nb_bytes < 0)
+    return static_cast<OPJ_OFF_T>(-1);
+
+  auto unsigned_nb_bytes =
+      static_cast<std::make_unsigned<OPJ_OFF_T>::type>(nb_bytes);
+  // Additionally, the offset may take us beyond the range of a size_t (e.g.
+  // 32-bit platforms). If so, just clamp at EOF.
+  if (unsigned_nb_bytes >
+      std::numeric_limits<OPJ_SIZE_T>::max() - srcData->offset) {
+    srcData->offset = srcData->src_size;
+  } else {
+    OPJ_SIZE_T checked_nb_bytes = static_cast<OPJ_SIZE_T>(unsigned_nb_bytes);
+    // Otherwise, mimic fseek() semantics to always succeed, even past EOF,
+    // clamping at EOF.  We can get away with this since we don't actually
+    // provide negative relative skips from beyond EOF back to inside the
+    // data, which would be the only reason to need to know exactly how far
+    // beyond EOF we are.
+    srcData->offset =
+        std::min(srcData->offset + checked_nb_bytes, srcData->src_size);
+  }
+  return nb_bytes;
+}
+
+OPJ_BOOL opj_seek_from_memory(OPJ_OFF_T nb_bytes, void* p_user_data) {
+  DecodeData* srcData = static_cast<DecodeData*>(p_user_data);
+  if (!srcData || !srcData->src_data || srcData->src_size == 0)
+    return OPJ_FALSE;
+
+  // Offsets are signed and may indicate a negative position, which would
+  // be before the start of the file. Do not support this.
+  if (nb_bytes < 0)
+    return OPJ_FALSE;
+
+  auto unsigned_nb_bytes =
+      static_cast<std::make_unsigned<OPJ_OFF_T>::type>(nb_bytes);
+  // Additionally, the offset may take us beyond the range of a size_t (e.g.
+  // 32-bit platforms). If so, just clamp at EOF.
+  if (unsigned_nb_bytes > std::numeric_limits<OPJ_SIZE_T>::max()) {
+    srcData->offset = srcData->src_size;
+  } else {
+    OPJ_SIZE_T checked_nb_bytes = static_cast<OPJ_SIZE_T>(nb_bytes);
+    // Otherwise, mimic fseek() semantics to always succeed, even past EOF,
+    // again clamping at EOF.
+    srcData->offset = std::min(checked_nb_bytes, srcData->src_size);
+  }
+  return OPJ_TRUE;
+}
+
+void sycc420_to_rgb(opj_image_t* img) {
+  if (!sycc420_size_is_valid(img))
+    return;
+
+  OPJ_UINT32 prec = img->comps[0].prec;
+  if (!prec)
+    return;
+
+  OPJ_UINT32 offset = 1 << (prec - 1);
+  OPJ_UINT32 upb = (1 << prec) - 1;
+  OPJ_UINT32 yw = img->comps[0].w;
+  OPJ_UINT32 yh = img->comps[0].h;
+  OPJ_UINT32 cbw = img->comps[1].w;
+  OPJ_UINT32 cbh = img->comps[1].h;
+  OPJ_UINT32 crw = img->comps[2].w;
+  bool extw = sycc420_must_extend_cbcr(yw, cbw);
+  bool exth = sycc420_must_extend_cbcr(yh, cbh);
+  FX_SAFE_UINT32 safe_size = yw;
+  safe_size *= yh;
+  safe_size *= sizeof(int);
+  if (!safe_size.IsValid())
+    return;
+
+  const int* y = img->comps[0].data;
+  const int* cb = img->comps[1].data;
+  const int* cr = img->comps[2].data;
+  if (!y || !cb || !cr)
+    return;
+
+  Optional<OpjImageRgbData> data = alloc_rgb(safe_size.ValueOrDie());
+  if (!data.has_value())
+    return;
+
+  int* r = data.value().r.get();
+  int* g = data.value().g.get();
+  int* b = data.value().b.get();
+  const int* ny = nullptr;
+  int* nr = nullptr;
+  int* ng = nullptr;
+  int* nb = nullptr;
+  OPJ_UINT32 i = 0;
+  OPJ_UINT32 j = 0;
+  for (i = 0; i < (yh & ~(OPJ_UINT32)1); i += 2) {
+    ny = y + yw;
+    nr = r + yw;
+    ng = g + yw;
+    nb = b + yw;
+    for (j = 0; j < (yw & ~(OPJ_UINT32)1); j += 2) {
+      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
+      ++y;
+      ++r;
+      ++g;
+      ++b;
+      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
+      ++y;
+      ++r;
+      ++g;
+      ++b;
+      sycc_to_rgb(offset, upb, *ny, *cb, *cr, nr, ng, nb);
+      ++ny;
+      ++nr;
+      ++ng;
+      ++nb;
+      sycc_to_rgb(offset, upb, *ny, *cb, *cr, nr, ng, nb);
+      ++ny;
+      ++nr;
+      ++ng;
+      ++nb;
+      ++cb;
+      ++cr;
+    }
+    if (j < yw) {
+      if (extw) {
+        --cb;
+        --cr;
+      }
+      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
+      ++y;
+      ++r;
+      ++g;
+      ++b;
+      sycc_to_rgb(offset, upb, *ny, *cb, *cr, nr, ng, nb);
+      ++ny;
+      ++nr;
+      ++ng;
+      ++nb;
+      ++cb;
+      ++cr;
+    }
+    y += yw;
+    r += yw;
+    g += yw;
+    b += yw;
+  }
+  if (i < yh) {
+    if (exth) {
+      cb -= cbw;
+      cr -= crw;
+    }
+    for (j = 0; j < (yw & ~(OPJ_UINT32)1); j += 2) {
+      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
+      ++y;
+      ++r;
+      ++g;
+      ++b;
+      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
+      ++y;
+      ++r;
+      ++g;
+      ++b;
+      ++cb;
+      ++cr;
+    }
+    if (j < yw) {
+      if (extw) {
+        --cb;
+        --cr;
+      }
+      sycc_to_rgb(offset, upb, *y, *cb, *cr, r, g, b);
+    }
+  }
+
+  opj_image_data_free(img->comps[0].data);
+  opj_image_data_free(img->comps[1].data);
+  opj_image_data_free(img->comps[2].data);
+  img->comps[0].data = data.value().r.release();
+  img->comps[1].data = data.value().g.release();
+  img->comps[2].data = data.value().b.release();
+  img->comps[1].w = yw;
+  img->comps[1].h = yh;
+  img->comps[2].w = yw;
+  img->comps[2].h = yh;
+  img->comps[1].dx = img->comps[0].dx;
+  img->comps[2].dx = img->comps[0].dx;
+  img->comps[1].dy = img->comps[0].dy;
+  img->comps[2].dy = img->comps[0].dy;
+}
+
+CJPX_Decoder::CJPX_Decoder(const RetainPtr<CPDF_ColorSpace>& cs)
+    : m_Image(nullptr),
+      m_Codec(nullptr),
+      m_DecodeData(nullptr),
+      m_Stream(nullptr),
+      m_ColorSpace(cs) {}
+
+CJPX_Decoder::~CJPX_Decoder() {
+  if (m_Codec)
+    opj_destroy_codec(m_Codec.Release());
+  if (m_Stream)
+    opj_stream_destroy(m_Stream.Release());
+  if (m_Image)
+    opj_image_destroy(m_Image.Release());
+}
+
+bool CJPX_Decoder::Init(pdfium::span<const uint8_t> src_data) {
+  static const unsigned char szJP2Header[] = {
+      0x00, 0x00, 0x00, 0x0c, 0x6a, 0x50, 0x20, 0x20, 0x0d, 0x0a, 0x87, 0x0a};
+  if (src_data.empty() || src_data.size() < sizeof(szJP2Header))
+    return false;
+
+  m_Image = nullptr;
+  m_SrcData = src_data;
+  m_DecodeData =
+      pdfium::MakeUnique<DecodeData>(src_data.data(), src_data.size());
+  m_Stream = fx_opj_stream_create_memory_stream(m_DecodeData.get());
+  if (!m_Stream)
+    return false;
+
+  opj_set_default_decoder_parameters(&m_Parameters);
+  m_Parameters.decod_format = 0;
+  m_Parameters.cod_format = 3;
+  if (memcmp(m_SrcData.data(), szJP2Header, sizeof(szJP2Header)) == 0) {
+    m_Codec = opj_create_decompress(OPJ_CODEC_JP2);
+    m_Parameters.decod_format = 1;
+  } else {
+    m_Codec = opj_create_decompress(OPJ_CODEC_J2K);
+  }
+  if (!m_Codec)
+    return false;
+
+  if (m_ColorSpace && m_ColorSpace->GetFamily() == PDFCS_INDEXED)
+    m_Parameters.flags |= OPJ_DPARAMETERS_IGNORE_PCLR_CMAP_CDEF_FLAG;
+  opj_set_info_handler(m_Codec.Get(), fx_ignore_callback, nullptr);
+  opj_set_warning_handler(m_Codec.Get(), fx_ignore_callback, nullptr);
+  opj_set_error_handler(m_Codec.Get(), fx_ignore_callback, nullptr);
+  if (!opj_setup_decoder(m_Codec.Get(), &m_Parameters))
+    return false;
+
+  m_Image = nullptr;
+  opj_image_t* pTempImage = nullptr;
+  if (!opj_read_header(m_Stream.Get(), m_Codec.Get(), &pTempImage))
+    return false;
+
+  m_Image = pTempImage;
+#ifndef USE_SYSTEM_LIBOPENJPEG2
+  m_Image->pdfium_use_colorspace = !!m_ColorSpace;
+#endif
+  return true;
+}
+
+bool CJPX_Decoder::StartDecode() {
+  if (!m_Parameters.nb_tile_to_decode) {
+    if (!opj_set_decode_area(m_Codec.Get(), m_Image.Get(), m_Parameters.DA_x0,
+                             m_Parameters.DA_y0, m_Parameters.DA_x1,
+                             m_Parameters.DA_y1)) {
+      opj_image_destroy(m_Image.Release());
+      return false;
+    }
+    if (!(opj_decode(m_Codec.Get(), m_Stream.Get(), m_Image.Get()) &&
+          opj_end_decompress(m_Codec.Get(), m_Stream.Get()))) {
+      opj_image_destroy(m_Image.Release());
+      return false;
+    }
+  } else if (!opj_get_decoded_tile(m_Codec.Get(), m_Stream.Get(), m_Image.Get(),
+                                   m_Parameters.tile_index)) {
+    return false;
+  }
+
+  opj_stream_destroy(m_Stream.Release());
+  if (m_Image->color_space != OPJ_CLRSPC_SYCC && m_Image->numcomps == 3 &&
+      m_Image->comps[0].dx == m_Image->comps[0].dy &&
+      m_Image->comps[1].dx != 1) {
+    m_Image->color_space = OPJ_CLRSPC_SYCC;
+  } else if (m_Image->numcomps <= 2) {
+    m_Image->color_space = OPJ_CLRSPC_GRAY;
+  }
+  if (m_Image->color_space == OPJ_CLRSPC_SYCC)
+    color_sycc_to_rgb(m_Image.Get());
+
+  if (m_Image->icc_profile_buf) {
+    // TODO(palmer): Using |opj_free| here resolves the crash described in
+    // https://crbug.com/737033, but ultimately we need to harmonize the
+    // memory allocation strategy across OpenJPEG and its PDFium callers.
+#ifndef USE_SYSTEM_LIBOPENJPEG2
+    opj_free(m_Image->icc_profile_buf);
+#else
+    free(m_Image->icc_profile_buf);
+#endif
+    m_Image->icc_profile_buf = nullptr;
+    m_Image->icc_profile_len = 0;
+  }
+  return true;
+}
+
+void CJPX_Decoder::GetInfo(uint32_t* width,
+                           uint32_t* height,
+                           uint32_t* components) {
+  *width = m_Image->x1;
+  *height = m_Image->y1;
+  *components = m_Image->numcomps;
+}
+
+bool CJPX_Decoder::Decode(uint8_t* dest_buf,
+                          uint32_t pitch,
+                          const std::vector<uint8_t>& offsets) {
+  if (m_Image->comps[0].w != m_Image->x1 || m_Image->comps[0].h != m_Image->y1)
+    return false;
+
+  if (pitch<(m_Image->comps[0].w * 8 * m_Image->numcomps + 31)>> 5 << 2) {
+    return false;
+  }
+
+  memset(dest_buf, 0xff, m_Image->y1 * pitch);
+  std::vector<uint8_t*> channel_bufs(m_Image->numcomps);
+  std::vector<int> adjust_comps(m_Image->numcomps);
+  for (uint32_t i = 0; i < m_Image->numcomps; i++) {
+    channel_bufs[i] = dest_buf + offsets[i];
+    adjust_comps[i] = m_Image->comps[i].prec - 8;
+    if (i > 0) {
+      if (m_Image->comps[i].dx != m_Image->comps[i - 1].dx ||
+          m_Image->comps[i].dy != m_Image->comps[i - 1].dy ||
+          m_Image->comps[i].prec != m_Image->comps[i - 1].prec) {
+        return false;
+      }
+    }
+  }
+  uint32_t width = m_Image->comps[0].w;
+  uint32_t height = m_Image->comps[0].h;
+  for (uint32_t channel = 0; channel < m_Image->numcomps; ++channel) {
+    uint8_t* pChannel = channel_bufs[channel];
+    if (adjust_comps[channel] < 0) {
+      for (uint32_t row = 0; row < height; ++row) {
+        uint8_t* pScanline = pChannel + row * pitch;
+        for (uint32_t col = 0; col < width; ++col) {
+          uint8_t* pPixel = pScanline + col * m_Image->numcomps;
+          if (!m_Image->comps[channel].data)
+            continue;
+
+          int src = m_Image->comps[channel].data[row * width + col];
+          src += m_Image->comps[channel].sgnd
+                     ? 1 << (m_Image->comps[channel].prec - 1)
+                     : 0;
+          if (adjust_comps[channel] > 0) {
+            *pPixel = 0;
+          } else {
+            *pPixel = static_cast<uint8_t>(src << -adjust_comps[channel]);
+          }
+        }
+      }
+    } else {
+      for (uint32_t row = 0; row < height; ++row) {
+        uint8_t* pScanline = pChannel + row * pitch;
+        for (uint32_t col = 0; col < width; ++col) {
+          uint8_t* pPixel = pScanline + col * m_Image->numcomps;
+          if (!m_Image->comps[channel].data)
+            continue;
+
+          int src = m_Image->comps[channel].data[row * width + col];
+          src += m_Image->comps[channel].sgnd
+                     ? 1 << (m_Image->comps[channel].prec - 1)
+                     : 0;
+          if (adjust_comps[channel] - 1 < 0) {
+            *pPixel = static_cast<uint8_t>((src >> adjust_comps[channel]));
+          } else {
+            int tmpPixel = (src >> adjust_comps[channel]) +
+                           ((src >> (adjust_comps[channel] - 1)) % 2);
+            tmpPixel = pdfium::clamp(tmpPixel, 0, 255);
+            *pPixel = static_cast<uint8_t>(tmpPixel);
+          }
+        }
+      }
+    }
+  }
+  return true;
+}