core/fxcodec/jpx/cjpx_decoder.h

// Copyright 2017 The PDFium Authors
// 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

#ifndef CORE_FXCODEC_JPX_CJPX_DECODER_H_
#define CORE_FXCODEC_JPX_CJPX_DECODER_H_

#include <stdint.h>

#include <memory>

#include "core/fxcrt/unowned_ptr.h"
#include "third_party/base/span.h"

#if defined(USE_SYSTEM_LIBOPENJPEG2)
#include <openjpeg.h>
#else
#include "third_party/libopenjpeg/openjpeg.h"
#endif

namespace fxcodec {

struct DecodeData;

class CJPX_Decoder {
 public:
  // Calculated as log2(2^32 / 1), where 2^32 is the largest image dimension and
  // 1 is the smallest required size.
  static constexpr uint8_t kMaxResolutionsToSkip = 32;

  enum ColorSpaceOption {
    kNoColorSpace,
    kNormalColorSpace,
    kIndexedColorSpace
  };

  struct JpxImageInfo {
    uint32_t width;
    uint32_t height;
    uint32_t components;
    COLOR_SPACE colorspace;
  };

  static std::unique_ptr<CJPX_Decoder> Create(
      pdfium::span<const uint8_t> src_span,
      CJPX_Decoder::ColorSpaceOption option,
      uint8_t resolution_levels_to_skip);

  static void Sycc420ToRgbForTesting(opj_image_t* img);

  ~CJPX_Decoder();

  JpxImageInfo GetInfo() const;
  bool StartDecode();

  // |swap_rgb| can only be set for images with 3 or more components.
  bool Decode(pdfium::span<uint8_t> dest_buf, uint32_t pitch, bool swap_rgb);

 private:
  // Use Create() to instantiate.
  explicit CJPX_Decoder(ColorSpaceOption option);

  bool Init(pdfium::span<const uint8_t> src_data,
            uint8_t resolution_levels_to_skip);

  const ColorSpaceOption m_ColorSpaceOption;
  pdfium::span<const uint8_t> m_SrcData;
  UnownedPtr<opj_image_t> m_Image;
  UnownedPtr<opj_codec_t> m_Codec;
  std::unique_ptr<DecodeData> m_DecodeData;
  UnownedPtr<opj_stream_t> m_Stream;
  opj_dparameters_t m_Parameters = {};
};

}  // namespace fxcodec

using fxcodec::CJPX_Decoder;

#endif  // CORE_FXCODEC_JPX_CJPX_DECODER_H_