Newer
Older
#include <cstdio> // for fread
// The file type is determined from the file extension.
enum FileType FileRead::get_file_type(const char *filename){
// find the last '.' in the file name
int dotposition=-1;
for(int i=strlen(filename)-1;i>=0;--i){
if(filename[i]=='.'){
dotposition=i;
break;
}
}
// if '.' was not found, the whole string is considered extension
char *ext=(char*)filename+dotposition+1; // file extension
if((ext[0]=='j'||ext[0]=='J')&&
(ext[1]=='p'||ext[1]=='P')&&
((strlen(ext)==3&&(ext[2]=='g'||ext[2]=='G'))||
(strlen(ext)==4&&(ext[2]=='e'||ext[2]=='E')&&
(ext[3]=='g'||ext[3]=='G')))){
return JPEG;
}
if((ext[0]=='p'||ext[0]=='P')&&
(ext[1]=='n'||ext[1]=='N')&&
(ext[2]=='g'||ext[2]=='G')){
return PNG;
}
if((ext[0]=='p'||ext[0]=='P')&&
(ext[1]=='n'||ext[1]=='b'||ext[1]=='g'||ext[1]=='p'||
ext[1]=='N'||ext[1]=='B'||ext[1]=='G'||ext[1]=='P')&&
(ext[2]=='m'||ext[2]=='M')){
return PNM;
}
return UNKNOWN;
}
unsigned char *FileRead::read_image(const char *new_image,int *width,int *height){
#ifndef _MSC_VER
// the progname is only used for reading the PNM format
const char * const progname=(char*)(PROGNAME);
#endif
switch(get_file_type(new_image)){
case JPEG:
fprintf(stderr,"input image has JPEG format\n");
return jpgRead(new_image,width,height);
break;
case PNG:
fprintf(stderr,"input image has PNG format\n");
return pngRead(new_image,width,height);
break;
#ifndef _MSC_VER
case PNM:
fprintf(stderr,"input image has PNM format\n");
return pnmRead(progname,new_image,width,height);
break;
#endif
default: // UNKNOWN
fprintf(stderr,"%s: unknown file format\n",new_image);
exit(-1);
}
return NULL;
}
const char *FileRead::image_types="All images (*.png *.jpg *.jpeg *.pnm *.pbm *.pgm *.ppm);;PNG images (*.png);;JPG images (*.jpg *.jpeg);;PBM images (*.pnm *.pbm *.pgm *.ppm);;All files (*)";
unsigned char *FileRead::jpgRead(const char *texturePath,
int *outImageWidth,
int *outImageHeight){
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
FILE *in_file;
FOPEN_RO(in_file,texturePath)
struct jpeg_decompress_struct cinfo;
struct jpeg_error_mgr jerr;
cinfo.err=jpeg_std_error(&jerr);
JSAMPROW row_pointer[1];
jpeg_create_decompress(&cinfo);
jpeg_stdio_src(&cinfo,in_file);
jpeg_read_header(&cinfo,0);
jpeg_start_decompress(&cinfo);
*outImageWidth=cinfo.output_width;
*outImageHeight=cinfo.output_height;
int depth=cinfo.num_components;
int textureSize=(*outImageWidth)*(*outImageHeight)*depth;
unsigned char *textureBytes=
(unsigned char*)malloc(textureSize*sizeof(unsigned char));
unsigned long scanline=*outImageHeight;
row_pointer[0]=(unsigned char*)malloc((*outImageWidth)*
depth*
sizeof(unsigned char));
while(cinfo.output_scanline<(unsigned)*outImageHeight){
--scanline;
jpeg_read_scanlines(&cinfo,row_pointer,1);
for(int i=0;i<(*outImageWidth)*depth;++i){
textureBytes[scanline*(*outImageWidth)*depth+i]=row_pointer[0][i];
}
}
fclose(in_file);
jpeg_finish_decompress(&cinfo);
jpeg_destroy_decompress(&cinfo);
return textureBytes;
}
unsigned char *FileRead::pngRead(const char *texturePath,
int *outImageWidth,
int *outImageHeight){
FILE *in_file;
FOPEN_RO(in_file,texturePath)
// read the header of the file
unsigned char header[8];
if(fread(header,1,8,in_file)!=(unsigned long)ftell(in_file)){
fprintf(stderr,"error reading %s\n",texturePath);
exit(-1);
}
// check the file is valid
if(png_sig_cmp(header,0,8)){
fprintf(stderr,"%s is not a valid PNG file!\n",texturePath);
exit(-1);
}
// initialize
png_structp png_ptr=png_create_read_struct(PNG_LIBPNG_VER_STRING,
if(!png_ptr){
fprintf(stderr,"error reading %s\n",texturePath);
exit(-1);
}
png_infop info_ptr=png_create_info_struct(png_ptr);
if (!info_ptr){
fprintf(stderr,"error reading %s\n",texturePath);
png_destroy_read_struct(&png_ptr,(png_infopp)NULL,(png_infopp)NULL);
exit(-1);
}
if(setjmp(png_jmpbuf(png_ptr))){
fprintf(stderr,"error reading %s\n",texturePath);
exit(-1);
}
png_init_io(png_ptr,in_file);
png_set_sig_bytes(png_ptr,8);
png_read_info(png_ptr,info_ptr);
*outImageWidth=png_get_image_width(png_ptr,info_ptr);
*outImageHeight=png_get_image_height(png_ptr,info_ptr);
png_byte color_type=png_get_color_type(png_ptr,info_ptr);
png_byte bit_depth=png_get_bit_depth(png_ptr,info_ptr);
if(bit_depth==16)
png_set_strip_16(png_ptr);
if(bit_depth<8)
png_set_expand_gray_1_2_4_to_8(png_ptr);
if(color_type==PNG_COLOR_TYPE_GRAY||color_type==PNG_COLOR_TYPE_GRAY_ALPHA)
png_set_gray_to_rgb(png_ptr);
if(color_type==PNG_COLOR_TYPE_PALETTE){
png_set_palette_to_rgb(png_ptr);
// TODO: Read the transparency values for indexed images;
// currently, they are ignored by stripping the alpha information.
png_set_strip_alpha(png_ptr);
}
png_read_update_info(png_ptr,info_ptr);
// allocate memory to store the texture
unsigned char *textureBytes=
(unsigned char*)malloc((*outImageWidth)*
(*outImageHeight)*
sizeof(unsigned char));
// read the contents of the file
if(setjmp(png_jmpbuf(png_ptr))){
fprintf(stderr,"error reading %s\n",texturePath);
exit(-1);
}
// TODO: we can avoid writing in row_pointers[] and later copying to
// the texture.
png_bytep *row_pointers=
(png_bytep*)malloc(sizeof(png_bytep)*(*outImageHeight));
for(int y=0;y<(*outImageHeight);++y)
row_pointers[y]=(png_byte*)malloc(png_get_rowbytes(png_ptr,info_ptr));
png_read_image(png_ptr,row_pointers);
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
switch(color_type){
case PNG_COLOR_TYPE_GRAY:
case PNG_COLOR_TYPE_PALETTE:
case PNG_COLOR_TYPE_RGB:
// RGB: copy directly RGB bits to the texture.
for(int row=0;row<(*outImageHeight);++row)
for(int j=0;j<(*outImageWidth);++j)
for(int k=0;k<3;++k)
textureBytes[row*(*outImageWidth)*3+j*3+k]=
row_pointers[(*outImageHeight)-row-1][j*3+k];
break;
case PNG_COLOR_TYPE_GRAY_ALPHA:
case PNG_COLOR_TYPE_RGB_ALPHA:
// RGBA: multiply each one of the three first bytes (channels R, G
// and B), by the alpha (the fourth byte).
for(int row=0;row<(*outImageHeight);++row)
for(int j=0;j<(*outImageWidth);++j)
for(int k=0;k<3;++k)
textureBytes[row*(*outImageWidth)*3+j*3+k]=
(double)
row_pointers[(*outImageHeight)-row-1][j*4+k]*
row_pointers[(*outImageHeight)-row-1][j*4+3]/
255;
break;
default:
fprintf(stderr,"%s: unrecognized PNG type\n",texturePath);
exit(-1);
png_read_end(png_ptr,NULL);
png_destroy_read_struct(&png_ptr,&info_ptr,NULL);
for(int row=0;row<(*outImageHeight);++row)
free(row_pointers[row]);
free(row_pointers);
fclose(in_file);
return textureBytes;
}
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
#ifndef _MSC_VER
unsigned char *FileRead::pnmRead(const char * const progname,
const char *texturePath,
int *outImageWidth,
int *outImageHeight){
struct pam inpam;
pm_init(progname, 0);
FILE *in_file;
FOPEN_RO(in_file,texturePath)
#ifdef PAM_STRUCT_SIZE
pnm_readpaminit(in_file,&inpam,PAM_STRUCT_SIZE(tuple_type));
#else
pnm_readpaminit(in_file,&inpam,sizeof(struct pam));
#endif
*outImageWidth=inpam.width;
*outImageHeight=inpam.height;
int textureSize=
(*outImageWidth)*
(*outImageHeight)*
inpam.depth*
inpam.bytes_per_sample;
unsigned char *textureBytes=
(unsigned char*)malloc(textureSize*sizeof(unsigned char));
tuple *tuplerow=pnm_allocpamrow(&inpam);
for(int row=0;row<*outImageHeight;row++) {
int column;
pnm_readpamrow(&inpam,tuplerow);
for (column=0;column<*outImageWidth;++column) {
unsigned int plane;
for(plane=0;plane<inpam.depth;++plane) {
textureBytes[((*outImageHeight)-row-1)*3*(*outImageWidth)+3*column+plane]=
tuplerow[column][plane];
}
}
}
pnm_freepamrow(tuplerow);
pm_close(in_file);
return textureBytes;
}
#endif