static int ppm_getrawsample(int fd, int const maxval)
{
if (maxval < 256) {
/* The sample is just one byte. Read it. */
return(ppm_getrawbyte(fd));
} else {
/* The sample is two bytes. Read both. */
unsigned char byte_pair[2];
if (rb->read(fd, byte_pair, 2) < 2) {
ppm_error("EOF. Read error while reading a long sample.");
return PLUGIN_ERROR;
}
return((byte_pair[0]<<8) | byte_pair[1]);
}
}
/* Read PPM file */
unsigned char* ppm_read(FILE* file,int& cols,int& rows){
unsigned char* pixels,*pix;
unsigned int r,g,b;
int format,maxval;
int row,col;
/* Get format */
format=ppm_readmagicnumber(file);
/* Get size */
cols=ppm_getint(file);
rows=ppm_getint(file);
maxval=ppm_getint(file);
if(maxval<=0 || maxval>1023){
fprintf(stderr,"Illegal maxval value: %d.\n",maxval);
exit(1);
}
/* Create memory */
pixels=(unsigned char*)malloc(3*rows*cols);
if(!pixels){
fprintf(stderr,"Image too big\n");
exit(1);
}
/* Load pixels */
pix=pixels;
switch(format){
case PPM_FORMAT:
for(row=0; row<rows; row++){
for(col=0; col<cols; col++){
r = (255*ppm_getint(file))/maxval;
g = (255*ppm_getint(file))/maxval;
b = (255*ppm_getint(file))/maxval;
*pix++ = r;
*pix++ = g;
*pix++ = b;
}
}
break;
case RPPM_FORMAT:
for(row=0; row<rows; row++){
for(col=0; col<cols; col++){
r = ppm_getrawbyte(file);
g = ppm_getrawbyte(file);
b = ppm_getrawbyte(file);
*pix++ = r;
*pix++ = g;
*pix++ = b;
}
}
break;
default:
fprintf(stderr,"Unknown format.\n");
exit(1);
break;
}
return pixels;
}