Simple Image Loading LibrarY  0.1.0
SILLYJPGImageContext.cpp
1 /***********************************************************************
2  filename: SILLYJPGImageContext.cpp
3  created: 11 Jun 2006
4  author: Olivier Delannoy
5 
6  purpose: Definition of the JPGImageContext class methods
7 *************************************************************************/
8 /***************************************************************************
9  * Copyright (C) 2004 - 2006 Paul D Turner & The CEGUI Development Team
10  *
11  * Permission is hereby granted, free of charge, to any person obtaining
12  * a copy of this software and associated documentation files (the
13  * "Software"), to deal in the Software without restriction, including
14  * without limitation the rights to use, copy, modify, merge, publish,
15  * distribute, sublicense, and/or sell copies of the Software, and to
16  * permit persons to whom the Software is furnished to do so, subject to
17  * the following conditions:
18  *
19  * The above copyright notice and this permission notice shall be
20  * included in all copies or substantial portions of the Software.
21  *
22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
23  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
25  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
26  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
27  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28  * OTHER DEALINGS IN THE SOFTWARE.
29  ***************************************************************************/
30 #ifdef HAVE_CONFIG_H
31 #include <config.h>
32 #endif
33 
34 #include "loaders/SILLYJPGImageContext.h"
35 
36 #ifndef SILLY_OPT_INLINE
37 #define inline
38 #include "loaders/SILLYJPGImageContext.icpp"
39 #undef inline
40 #endif
41 
42 #include <jpeglib.h>
43 
44 // Start section of namespace SILLY
45 namespace SILLY
46 {
47 
48 
49 void JPG_init_source(j_decompress_ptr cinfo)
50 {
51  // Nothing to do
52 }
53 
54 boolean JPG_fill_input_buffer(j_decompress_ptr cinfo)
55 {
56  JPGImageContext* jpg = reinterpret_cast<JPGImageContext*>(cinfo->client_data);
57  cinfo->src->next_input_byte = jpg->d_source->getDataPtr();
58  cinfo->src->bytes_in_buffer = jpg->d_source->getSize();
59  return TRUE;
60 }
61 
62 void JPG_skip_input_data(j_decompress_ptr cinfo, long num_bytes)
63 {
64  if (num_bytes > 0)
65  {
66  cinfo->src->next_input_byte += (size_t)num_bytes;
67  cinfo->src->bytes_in_buffer -= (size_t)num_bytes;
68  }
69 }
70 
71 void JPG_term_source(j_decompress_ptr cinfo)
72 {
73  // Nothing to do
74 }
75 
76 void JPG_error_exit(j_common_ptr cinfo)
77 {
78  JPGImageContext* jpg = reinterpret_cast<JPGImageContext*>(cinfo->client_data);
79  // TODO
80  longjmp(jpg->setjmp_buffer, 1);
81 
82 }
83 
84 void JPG_emit_message(j_common_ptr cinfo, int msg_level)
85 {
86  // Ignore
87 }
88 
89 
90 JPGImageContext::JPGImageContext()
91  : ImageContext(0, 0)
92 {
93  src_mgr.bytes_in_buffer = 0;
94  src_mgr.next_input_byte = 0;
95  src_mgr.init_source = JPG_init_source;
96  src_mgr.fill_input_buffer = JPG_fill_input_buffer;
97  src_mgr.skip_input_data = JPG_skip_input_data;
98  src_mgr.resync_to_restart = jpeg_resync_to_restart;
99  src_mgr.term_source = JPG_term_source;
100  jpeg_create_decompress(&cinfo);
101  cinfo.src = &src_mgr;
102  cinfo.client_data = this;
103  cinfo.err = jpeg_std_error(&d_error_mgr);
104  d_error_mgr.error_exit = JPG_error_exit;
105 
106 }
107 
108 
109 JPGImageContext::~JPGImageContext()
110 {
111  jpeg_destroy_decompress(&cinfo);
112 }
113 
114 
115 void JPGImageContext::setImageSize()
116 {
117  setWidth(cinfo.output_width);
118  setHeight(cinfo.output_height);
119 }
120 
121 } // End section of namespace SILLY