Exiv2
pngchunk_int.hpp
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3  * Copyright (C) 2004-2018 Exiv2 authors
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12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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29  /*
30  File: pngchunk.cpp
31  */
32 
33 #ifndef PNGCHUNK_INT_HPP_
34 #define PNGCHUNK_INT_HPP_
35 
36 // *****************************************************************************
37 // included header files
38 #include "types.hpp"
39 #include "pngimage.hpp"
40 
41 // + standard includes
42 #include <iosfwd>
43 #include <cassert>
44 #include <cstdarg>
45 
46 // *****************************************************************************
47 // namespace extensions
48 namespace Exiv2 {
49 
50 // *****************************************************************************
51 // class declarations
52  class Image;
53 
54  namespace Internal {
55 
56 // *****************************************************************************
57 // class definitions
58 
63  class PngChunk {
64  public:
68  enum TxtChunkType {
69  tEXt_Chunk = 0,
70  zTXt_Chunk = 1,
71  iTXt_Chunk = 2
72  };
73 
74  public:
83  static void decodeIHDRChunk(const DataBuf& data,
84  int* outWidth,
85  int* outHeight);
86 
95  static void decodeTXTChunk(Image* pImage,
96  const DataBuf& data,
97  TxtChunkType type);
98 
106  static DataBuf decodeTXTChunk(const DataBuf& data,
107  TxtChunkType type);
108 
109 
116  static DataBuf keyTXTChunk(const DataBuf& data, bool stripHeader=false);
117 
126  static std::string makeMetadataChunk(const std::string& metadata,
127  MetadataId type);
128 
129  private:
134  static DataBuf parseTXTChunk(const DataBuf& data,
135  int keysize,
136  TxtChunkType type);
137 
147  static void parseChunkContent( Image* pImage,
148  const byte* key,
149  long keySize,
150  const DataBuf arr);
151 
162  static std::string makeAsciiTxtChunk(const std::string& keyword,
163  const std::string& text,
164  bool compress);
165 
174  static std::string makeUtf8TxtChunk(const std::string& keyword,
175  const std::string& text,
176  bool compress);
177 
181  static void zlibUncompress(const byte* compressedText,
182  unsigned int compressedTextSize,
183  DataBuf& arr);
184 
188  static std::string zlibCompress(const std::string& text);
189 
193  static DataBuf readRawProfile(const DataBuf& text,bool iTXt);
194 
199  static std::string writeRawProfile(const std::string& profileData,
200  const char* profileType);
201 
202  friend class Exiv2::PngImage;
203 
204  }; // class PngChunk
205 
206 }} // namespace Internal, Exiv2
207 
208 #endif // #ifndef PNGCHUNK_INT_HPP_
Utility class containing a character array. All it does is to take care of memory allocation and dele...
Definition: types.hpp:204
Abstract base class defining the interface for an image. This is the top-level interface to the Exiv2...
Definition: image.hpp:81
Stateless parser class for data in PNG chunk format. Images use this class to decode and encode PNG-b...
Definition: pngchunk_int.hpp:63
static DataBuf decodeTXTChunk(const DataBuf &data, TxtChunkType type)
Decode PNG tEXt, zTXt, or iTXt chunk data from pImage passed by data buffer data and extract Comment,...
static void decodeIHDRChunk(const DataBuf &data, int *outWidth, int *outHeight)
Decode PNG IHDR chunk data from a data buffer data and return image size to outWidth and outHeight.
static DataBuf keyTXTChunk(const DataBuf &data, bool stripHeader=false)
Return PNG TXT chunk key as data buffer.
TxtChunkType
Text Chunk types.
Definition: pngchunk_int.hpp:68
static void decodeTXTChunk(Image *pImage, const DataBuf &data, TxtChunkType type)
Decode PNG tEXt, zTXt, or iTXt chunk data from pImage passed by data buffer data and extract Comment,...
static std::string makeMetadataChunk(const std::string &metadata, MetadataId type)
Return a complete PNG chunk data compressed or not as buffer. Data returned is formated accordingly w...
Class to access PNG images. Exif and IPTC metadata are supported directly.
Definition: pngimage.hpp:58
Provides classes and functions to encode and decode Exif and Iptc data. The libexiv2 API consists of ...
Definition: asfvideo.hpp:36
@ string
IPTC string type.
Definition: types.hpp:147
MetadataId
An identifier for each type of metadata.
Definition: types.hpp:119
PNG image, implemented using the following references: PNG specification by W3C PNG tags list by Phi...
Type definitions for Exiv2 and related functionality.