text: /*
    Copyright 2008 Larry Gritz and the other authors and contributors.
    All Rights Reserved.
  
    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are
    met:
    * Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.
    * Neither the name of the software's owners nor the names of its
      contributors may be used to endorse or promote products derived from
      this software without specific prior written permission.
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
    (This is the Modified BSD License)
  */
  
  
  /////////////////////////////////////////////////////////////////////////////
  // Private definitions internal to the jpeg.imageio plugin
  /////////////////////////////////////////////////////////////////////////////
  
  
  #pragma once
  
  #include <csetjmp>
  
  #ifdef WIN32
  #    undef FAR
  #    define XMD_H
  #endif
  
  extern "C" {
  #include "jpeglib.h"
  }
  
  
  OIIO_PLUGIN_NAMESPACE_BEGIN
  
  
  #define MAX_DATA_BYTES_IN_MARKER 65519L
  #define ICC_HEADER_SIZE 14
  #define ICC_PROFILE_ATTR "ICCProfile"
  
  // Chroma sub-sampling values for jpeg_compress_struct / jpeg_component_info
  #define JPEG_SUBSAMPLING_ATTR "jpeg:subsampling"
  #define JPEG_444_STR "4:4:4"
  #define JPEG_422_STR "4:2:2"
  #define JPEG_420_STR "4:2:0"
  #define JPEG_411_STR "4:1:1"
  
  static const int JPEG_444_COMP[6] = { 1, 1, 1, 1, 1, 1 };
  static const int JPEG_422_COMP[6] = { 2, 1, 1, 1, 1, 1 };
  static const int JPEG_420_COMP[6] = { 2, 2, 1, 1, 1, 1 };
  static const int JPEG_411_COMP[6] = { 4, 1, 1, 1, 1, 1 };
  
  
  class JpgInput final : public ImageInput {
  public:
      JpgInput() { init(); }
      virtual ~JpgInput() { close(); }
      virtual const char* format_name(void) const override { return "jpeg"; }
      virtual int supports(string_view feature) const override
      {
          return (feature == "exif" || feature == "iptc");
      }
      virtual bool valid_file(const std::string& filename) const override;
      virtual bool open(const std::string& name, ImageSpec& spec) override;
      virtual bool open(const std::string& name, ImageSpec& spec,
                        const ImageSpec& config) override;
      virtual bool read_native_scanline(int subimage, int miplevel, int y, int z,
                                        void* data) override;
      virtual bool close() override;
      const std::string& filename() const { return m_filename; }
      void* coeffs() const { return m_coeffs; }
      struct my_error_mgr {
          struct jpeg_error_mgr pub; /* "public" fields */
          jmp_buf setjmp_buffer;     /* for return to caller */
          JpgInput* jpginput;        /* back pointer to *this */
      };
      typedef struct my_error_mgr* my_error_ptr;
  
      // Called by my_error_exit
      void jpegerror(my_error_ptr myerr, bool fatal = false);
  
  private:
      FILE* m_fd;
      std::string m_filename;
      int m_next_scanline;  // Which scanline is the next to read?
      bool m_raw;           // Read raw coefficients, not scanlines
      bool m_cmyk;          // The input file is cmyk
      bool m_fatalerr;      // JPEG reader hit a fatal error
      struct jpeg_decompress_struct m_cinfo;
      my_error_mgr m_jerr;
      jvirt_barray_ptr* m_coeffs;
      std::vector<unsigned char> m_cmyk_buf;  // For CMYK translation
  
      void init()
      {
          m_fd            = NULL;
          m_raw           = false;
          m_cmyk          = false;
          m_fatalerr      = false;
          m_coeffs        = NULL;
          m_jerr.jpginput = this;
      }
  
      // Rummage through the JPEG "APP1" marker pointed to by buf, decoding
      // IPTC (International Press Telecommunications Council) metadata
      // information and adding attributes to spec.  This assumes it's in
      // the form of an IIM (Information Interchange Model), which is actually
      // considered obsolete and is replaced by an XML scheme called XMP.
      void jpeg_decode_iptc(const unsigned char* buf);
  
      bool read_icc_profile(j_decompress_ptr cinfo, ImageSpec& spec);
  
      void close_file()
      {
          if (m_fd)
              fclose(m_fd);  // N.B. the init() will set m_fd to NULL
          init();
      }
  
      friend class JpgOutput;
  };
  
  
  
  OIIO_PLUGIN_NAMESPACE_END
  