Compressor.h

/*  Generic compressor class - extended by JPEG and PNG Compressor classes
 
    Copyright (C) 2017-2025 Ruven Pillay
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software Foundation,
    Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
*/
 
 
#ifndef _COMPRESSOR_H
#define _COMPRESSOR_H
 
 
 
#include "RawTile.h"
#include <map>
 
 
class Compressor {
 
 protected:
 
  int Q;
 
  bool default_quality;
 
  unsigned char *header;
 
  unsigned int header_size;
 
  int dpi_units;
 
  float dpi_x;
 
  float dpi_y;
 
  std::map <const std::string, const std::string> metadata;
 
  std::string icc;
 
  bool embedICC;
 
  std::string xmp;
 
  bool embedXMP;
 
  std::string exif;
 
  bool embedEXIF;
 
  virtual void writeMetadata() {};
 
  virtual void writeResolution() {};
 
  virtual void writeICCProfile() {};
 
  virtual void writeXMPMetadata() {};
 
  virtual void writeExifMetadata() {};
 
 
 public:
 
 
  Compressor( int compressionLevel ) :
    Q( compressionLevel ),
    default_quality( true ),
    header( NULL ),
    header_size( 0 ),
    dpi_units( 0 ),
    dpi_x( 0 ),
    dpi_y( 0 ),
    embedICC( false ),
    embedXMP( false ),
    embedEXIF( false ) {};
 
 
  virtual ~Compressor() {};
 
 
 
  unsigned int getHeaderSize() const { return header_size; };
 
 
 
  unsigned char* getHeader() { return header; };
 
 
  inline int getQuality() const { return Q; }
 
 
  inline bool defaultQuality() const { return default_quality; }
 
 
  inline void setResolution( float x, float y, int units ){ dpi_x = x; dpi_y = y; dpi_units = units; };
 
 
 
  inline void embedICCProfile( const bool embed ){ this->embedICC = embed; }
 
 
 
  inline void embedXMPMetadata( const bool embed ){ this->embedXMP = embed; }
 
 
  inline void embedExifMetadata( const bool embed ){ this->embedEXIF = embed; }
 
 
  inline void setMetadata( const std::map <const std::string, const std::string>& metadata )
  {
    this->metadata = std::map <const std::string, const std::string>( metadata );
 
    // Extract ICC profile if it exists and remove from list
    std::map<const std::string, const std::string> :: const_iterator it;
    it = this->metadata.find("icc");
    if( it != this->metadata.end() ){
      icc = it->second;
      this->metadata.erase( it );
    }
 
    // Extract XMP chunk if it exists and remove from list
    it = this->metadata.find("xmp");
    if( it != this->metadata.end() ){
      xmp = it->second;
      this->metadata.erase( it );
    }
 
    // Extract EXIF chunk if it exists and remove from list
    it = this->metadata.find("exif");
    if( it != this->metadata.end() ){
      exif = it->second;
      this->metadata.erase( it );
    }
 
  };
 
 
 
  virtual void setQuality( int quality ) {};
 
 
 
  virtual void InitCompression( const RawTile& rawtile, unsigned int strip_height ) {};
 
 
 
  virtual unsigned int CompressStrip( unsigned char* s, unsigned char* o, unsigned int tile_height ) { return 0; };
 
 
 
  virtual unsigned int Finish( unsigned char* output ) { return 0; };
 
 
 
  virtual unsigned int Compress( RawTile& t ) { return 0; };
 
 
 
  virtual const char* getMimeType() const { return "image/example"; };
 
 
 
  virtual const char* getSuffix() const { return "img"; };
 
 
 
  virtual ImageEncoding getImageEncoding() const { return ImageEncoding::RAW; };
 
 
 
  virtual void injectMetadata( RawTile& t ) {};
 
};
 
#endif