aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/libraries/irrlicht-1.8/source/Irrlicht/CImageLoaderJPG.cpp
blob: 877a4d7b39934f05fb5b3afb6b691d1afe322b33 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
// Copyright (C) 2002-2012 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#include "CImageLoaderJPG.h"

#ifdef _IRR_COMPILE_WITH_JPG_LOADER_

#include "IReadFile.h"
#include "CImage.h"
#include "os.h"
#include "irrString.h"

namespace irr
{
namespace video
{

// Static members
io::path CImageLoaderJPG::Filename;

//! constructor
CImageLoaderJPG::CImageLoaderJPG()
{
	#ifdef _DEBUG
	setDebugName("CImageLoaderJPG");
	#endif
}



//! destructor
CImageLoaderJPG::~CImageLoaderJPG()
{
}



//! returns true if the file maybe is able to be loaded by this class
//! based on the file extension (e.g. ".tga")
bool CImageLoaderJPG::isALoadableFileExtension(const io::path& filename) const
{
	return core::hasFileExtension ( filename, "jpg", "jpeg" );
}


#ifdef _IRR_COMPILE_WITH_LIBJPEG_

    // struct for handling jpeg errors
    struct irr_jpeg_error_mgr
    {
        // public jpeg error fields
        struct jpeg_error_mgr pub;

        // for longjmp, to return to caller on a fatal error
        jmp_buf setjmp_buffer;
    };

void CImageLoaderJPG::init_source (j_decompress_ptr cinfo)
{
	// DO NOTHING
}



boolean CImageLoaderJPG::fill_input_buffer (j_decompress_ptr cinfo)
{
	// DO NOTHING
	return 1;
}



void CImageLoaderJPG::skip_input_data (j_decompress_ptr cinfo, long count)
{
	jpeg_source_mgr * src = cinfo->src;
	if(count > 0)
	{
		src->bytes_in_buffer -= count;
		src->next_input_byte += count;
	}
}



void CImageLoaderJPG::term_source (j_decompress_ptr cinfo)
{
	// DO NOTHING
}


void CImageLoaderJPG::error_exit (j_common_ptr cinfo)
{
	// unfortunately we need to use a goto rather than throwing an exception
	// as gcc crashes under linux crashes when using throw from within
	// extern c code

	// Always display the message
	(*cinfo->err->output_message) (cinfo);

	// cinfo->err really points to a irr_error_mgr struct
	irr_jpeg_error_mgr *myerr = (irr_jpeg_error_mgr*) cinfo->err;

	longjmp(myerr->setjmp_buffer, 1);
}


void CImageLoaderJPG::output_message(j_common_ptr cinfo)
{
	// display the error message.
	c8 temp1[JMSG_LENGTH_MAX];
	(*cinfo->err->format_message)(cinfo, temp1);
	core::stringc errMsg("JPEG FATAL ERROR in ");
	errMsg += core::stringc(Filename);
	os::Printer::log(errMsg.c_str(),temp1, ELL_ERROR);
}
#endif // _IRR_COMPILE_WITH_LIBJPEG_

//! returns true if the file maybe is able to be loaded by this class
bool CImageLoaderJPG::isALoadableFileFormat(io::IReadFile* file) const
{
	#ifndef _IRR_COMPILE_WITH_LIBJPEG_
	return false;
	#else

	if (!file)
		return false;

	s32 jfif = 0;
	file->seek(6);
	file->read(&jfif, sizeof(s32));
	return (jfif == 0x4a464946 || jfif == 0x4649464a);

	#endif
}

//! creates a surface from the file
IImage* CImageLoaderJPG::loadImage(io::IReadFile* file) const
{
	#ifndef _IRR_COMPILE_WITH_LIBJPEG_
	os::Printer::log("Can't load as not compiled with _IRR_COMPILE_WITH_LIBJPEG_:", file->getFileName(), ELL_DEBUG);
	return 0;
	#else

	if (!file)
		return 0;

	Filename = file->getFileName();

	u8 **rowPtr=0;
	u8* input = new u8[file->getSize()];
	file->read(input, file->getSize());

	// allocate and initialize JPEG decompression object
	struct jpeg_decompress_struct cinfo;
	struct irr_jpeg_error_mgr jerr;

	//We have to set up the error handler first, in case the initialization
	//step fails.  (Unlikely, but it could happen if you are out of memory.)
	//This routine fills in the contents of struct jerr, and returns jerr's
	//address which we place into the link field in cinfo.

	cinfo.err = jpeg_std_error(&jerr.pub);
	cinfo.err->error_exit = error_exit;
	cinfo.err->output_message = output_message;

	// compatibility fudge:
	// we need to use setjmp/longjmp for error handling as gcc-linux
	// crashes when throwing within external c code
	if (setjmp(jerr.setjmp_buffer))
	{
		// If we get here, the JPEG code has signaled an error.
		// We need to clean up the JPEG object and return.

		jpeg_destroy_decompress(&cinfo);

		delete [] input;
		// if the row pointer was created, we delete it.
		if (rowPtr)
			delete [] rowPtr;

		// return null pointer
		return 0;
	}

	// Now we can initialize the JPEG decompression object.
	jpeg_create_decompress(&cinfo);

	// specify data source
	jpeg_source_mgr jsrc;

	// Set up data pointer
	jsrc.bytes_in_buffer = file->getSize();
	jsrc.next_input_byte = (JOCTET*)input;
	cinfo.src = &jsrc;

	jsrc.init_source = init_source;
	jsrc.fill_input_buffer = fill_input_buffer;
	jsrc.skip_input_data = skip_input_data;
	jsrc.resync_to_restart = jpeg_resync_to_restart;
	jsrc.term_source = term_source;

	// Decodes JPG input from whatever source
	// Does everything AFTER jpeg_create_decompress
	// and BEFORE jpeg_destroy_decompress
	// Caller is responsible for arranging these + setting up cinfo

	// read file parameters with jpeg_read_header()
	jpeg_read_header(&cinfo, TRUE);

	bool useCMYK=false;
	if (cinfo.jpeg_color_space==JCS_CMYK)
	{
		cinfo.out_color_space=JCS_CMYK;
		cinfo.out_color_components=4;
		useCMYK=true;
	}
	else
	{
		cinfo.out_color_space=JCS_RGB;
		cinfo.out_color_components=3;
	}
	cinfo.output_gamma=2.2;
	cinfo.do_fancy_upsampling=FALSE;

	// Start decompressor
	jpeg_start_decompress(&cinfo);

	// Get image data
	u16 rowspan = cinfo.image_width * cinfo.out_color_components;
	u32 width = cinfo.image_width;
	u32 height = cinfo.image_height;

	// Allocate memory for buffer
	u8* output = new u8[rowspan * height];

	// Here we use the library's state variable cinfo.output_scanline as the
	// loop counter, so that we don't have to keep track ourselves.
	// Create array of row pointers for lib
	rowPtr = new u8* [height];

	for( u32 i = 0; i < height; i++ )
		rowPtr[i] = &output[ i * rowspan ];

	u32 rowsRead = 0;

	while( cinfo.output_scanline < cinfo.output_height )
		rowsRead += jpeg_read_scanlines( &cinfo, &rowPtr[rowsRead], cinfo.output_height - rowsRead );

	delete [] rowPtr;
	// Finish decompression

	jpeg_finish_decompress(&cinfo);

	// Release JPEG decompression object
	// This is an important step since it will release a good deal of memory.
	jpeg_destroy_decompress(&cinfo);

	// convert image
	IImage* image = 0;
	if (useCMYK)
	{
		image = new CImage(ECF_R8G8B8,
				core::dimension2d<u32>(width, height));
		const u32 size = 3*width*height;
		u8* data = (u8*)image->lock();
		if (data)
		{
			for (u32 i=0,j=0; i<size; i+=3, j+=4)
			{
				// Also works without K, but has more contrast with K multiplied in
//				data[i+0] = output[j+2];
//				data[i+1] = output[j+1];
//				data[i+2] = output[j+0];
				data[i+0] = (char)(output[j+2]*(output[j+3]/255.f));
				data[i+1] = (char)(output[j+1]*(output[j+3]/255.f));
				data[i+2] = (char)(output[j+0]*(output[j+3]/255.f));
			}
		}
		image->unlock();
		delete [] output;
	}
	else
		image = new CImage(ECF_R8G8B8,
				core::dimension2d<u32>(width, height), output);

	delete [] input;

	return image;

	#endif
}



//! creates a loader which is able to load jpeg images
IImageLoader* createImageLoaderJPG()
{
	return new CImageLoaderJPG();
}

} // end namespace video
} // end namespace irr

#endif