Panda3D
pnmFileTypeJPG.h
1 // Filename: pnmFileTypeJPG.h
2 // Created by: mike (17Jun00)
3 //
4 ////////////////////////////////////////////////////////////////////
5 //
6 // PANDA 3D SOFTWARE
7 // Copyright (c) Carnegie Mellon University. All rights reserved.
8 //
9 // All use of this software is subject to the terms of the revised BSD
10 // license. You should have received a copy of this license along
11 // with this source code in a file named "LICENSE."
12 //
13 ////////////////////////////////////////////////////////////////////
14 
15 #ifndef PNMFILETYPEJPG_H
16 #define PNMFILETYPEJPG_H
17 
18 #include "pandabase.h"
19 
20 #ifdef HAVE_JPEG
21 
22 #include "pnmFileType.h"
23 #include "pnmReader.h"
24 #include "pnmWriter.h"
25 
26 #if defined(_WIN32)
27 #ifndef WIN32_LEAN_AND_MEAN
28 #define WIN32_LEAN_AND_MEAN 1
29 #endif
30 #include <windows.h> // we need to include this before jpeglib.
31 #endif
32 
33 #ifdef HAVE_PNG
34 // If we are going to be including png.h (in the unrelated file
35 // pnmFileTypePNG.h), be sure to include it before including setjmp.h.
36 // Ugly hack due to png weirdness with setjmp.
37 #include <png.h>
38 #endif
39 
40 
41 extern "C" {
42 #include <stdio.h> // jpeglib requires this to be included first.
43 #include <jpeglib.h>
44 #include <setjmp.h>
45 }
46 
47 ////////////////////////////////////////////////////////////////////
48 // Class : PNMFileTypeJPG
49 // Description : For reading and writing Jpeg files.
50 ////////////////////////////////////////////////////////////////////
51 class EXPCL_PANDA_PNMIMAGETYPES PNMFileTypeJPG : public PNMFileType {
52 public:
53  PNMFileTypeJPG();
54 
55  virtual string get_name() const;
56 
57  virtual int get_num_extensions() const;
58  virtual string get_extension(int n) const;
59  virtual string get_suggested_extension() const;
60 
61  virtual bool has_magic_number() const;
62  virtual bool matches_magic_number(const string &magic_number) const;
63 
64  virtual PNMReader *make_reader(istream *file, bool owns_file = true,
65  const string &magic_number = string());
66  virtual PNMWriter *make_writer(ostream *file, bool owns_file = true);
67 
68 public:
69  class Reader : public PNMReader {
70  public:
71  Reader(PNMFileType *type, istream *file, bool owns_file, string magic_number);
72  ~Reader();
73 
74  virtual void prepare_read();
75  virtual int read_data(xel *array, xelval *alpha);
76 
77  private:
78  struct jpeg_decompress_struct _cinfo;
79  struct my_error_mgr {
80  struct jpeg_error_mgr pub;
81  jmp_buf setjmp_buffer;
82  };
83  typedef struct my_error_mgr *_my_error_ptr;
84  struct my_error_mgr _jerr;
85  unsigned long pos;
86 
87  unsigned long offBits;
88 
89  unsigned short cBitCount;
90  int indexed;
91  int classv;
92 
93  pixval R[256]; /* reds */
94  pixval G[256]; /* greens */
95  pixval B[256]; /* blues */
96 
97  bool _is_valid;
98  };
99 
100  class Writer : public PNMWriter {
101  public:
102  Writer(PNMFileType *type, ostream *file, bool owns_file);
103 
104  virtual int write_data(xel *array, xelval *alpha);
105  };
106 
107 
108  // The TypedWritable interface follows.
109 public:
110  static void register_with_read_factory();
111 
112 protected:
113  static TypedWritable *make_PNMFileTypeJPG(const FactoryParams &params);
114 
115 public:
116  static TypeHandle get_class_type() {
117  return _type_handle;
118  }
119  static void init_type() {
120  PNMFileType::init_type();
121  register_type(_type_handle, "PNMFileTypeJPG",
122  PNMFileType::get_class_type());
123  }
124  virtual TypeHandle get_type() const {
125  return get_class_type();
126  }
127  virtual TypeHandle force_init_type() {init_type(); return get_class_type();}
128 
129 private:
130  static TypeHandle _type_handle;
131 };
132 
133 #endif // HAVE_JPEG
134 
135 #endif
136 
virtual string get_extension(int n) const
Returns the nth possible filename extension associated with this particular file type, without a leading dot.
Definition: pnmFileType.cxx:62
virtual PNMWriter * make_writer(ostream *file, bool owns_file=true)
Allocates and returns a new PNMWriter suitable for reading from this file type, if possible...
Base class for objects that can be written to and read from Bam files.
Definition: typedWritable.h:37
This is the base class of a family of classes that represent particular image file types that PNMImag...
Definition: pnmFileType.h:35
virtual PNMReader * make_reader(istream *file, bool owns_file=true, const string &magic_number=string())
Allocates and returns a new PNMReader suitable for reading from this file type, if possible...
virtual bool matches_magic_number(const string &magic_number) const
Returns true if the indicated "magic number" byte stream (the initial few bytes read from the file) m...
An instance of this class is passed to the Factory when requesting it to do its business and construc...
Definition: factoryParams.h:40
This is an abstract base class that defines the interface for reading image files of various types...
Definition: pnmReader.h:31
This is an abstract base class that defines the interface for writing image files of various types...
Definition: pnmWriter.h:31
virtual bool has_magic_number() const
Returns true if this particular file type uses a magic number to identify it, false otherwise...
Definition: pnmFileType.cxx:89
TypeHandle is the identifier used to differentiate C++ class types.
Definition: typeHandle.h:85
virtual int get_num_extensions() const
Returns the number of different possible filename extensions associated with this particular file typ...
Definition: pnmFileType.cxx:50
virtual string get_suggested_extension() const
Returns a suitable filename extension (without a leading dot) to suggest for files of this type...
Definition: pnmFileType.cxx:75