Exiv2
pngchunk_int.hpp
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20 #ifndef PNGCHUNK_INT_HPP_
21 #define PNGCHUNK_INT_HPP_
22 
23 // *****************************************************************************
24 // included header files
25 #include "types.hpp"
26 #include "pngimage.hpp"
27 
28 // + standard includes
29 #include <iosfwd>
30 #include <cassert>
31 #include <cstdarg>
32 
33 // *****************************************************************************
34 // namespace extensions
35 namespace Exiv2 {
36 
37 // *****************************************************************************
38 // class declarations
39  class Image;
40 
41  namespace Internal {
42 
43 // *****************************************************************************
44 // class definitions
45 
50  class PngChunk {
51  public:
55  enum TxtChunkType {
56  tEXt_Chunk = 0,
57  zTXt_Chunk = 1,
58  iTXt_Chunk = 2
59  };
60 
61  public:
70  static void decodeIHDRChunk(const DataBuf& data,
71  int* outWidth,
72  int* outHeight);
73 
82  static void decodeTXTChunk(Image* pImage,
83  const DataBuf& data,
84  TxtChunkType type);
85 
93  static DataBuf decodeTXTChunk(const DataBuf& data,
94  TxtChunkType type);
95 
96 
103  static DataBuf keyTXTChunk(const DataBuf& data, bool stripHeader=false);
104 
113  static std::string makeMetadataChunk(const std::string& metadata,
114  MetadataId type);
115 
116  private:
121  static DataBuf parseTXTChunk(const DataBuf& data,
122  int keysize,
123  TxtChunkType type);
124 
134  static void parseChunkContent( Image* pImage,
135  const byte* key,
136  long keySize,
137  const DataBuf arr);
138 
149  static std::string makeAsciiTxtChunk(const std::string& keyword,
150  const std::string& text,
151  bool compress);
152 
161  static std::string makeUtf8TxtChunk(const std::string& keyword,
162  const std::string& text,
163  bool compress);
164 
168  static void zlibUncompress(const byte* compressedText,
169  unsigned int compressedTextSize,
170  DataBuf& arr);
171 
175  static std::string zlibCompress(const std::string& text);
176 
180  static DataBuf readRawProfile(const DataBuf& text,bool iTXt);
181 
186  static std::string writeRawProfile(const std::string& profileData,
187  const char* profileType);
188 
189  friend class Exiv2::PngImage;
190 
191  }; // class PngChunk
192 
193 }} // namespace Internal, Exiv2
194 
195 #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:193
Abstract base class defining the interface for an image. This is the top-level interface to the Exiv2...
Definition: image.hpp:78
Stateless parser class for data in PNG chunk format. Images use this class to decode and encode PNG-b...
Definition: pngchunk_int.hpp:50
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:55
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:47
Provides classes and functions to encode and decode Exif and Iptc data. The libexiv2 API consists of ...
Definition: asfvideo.hpp:36
MetadataId
An identifier for each type of metadata.
Definition: types.hpp:108