CImg的使用，入门

CImg的使用：
const char *imageIN="image.jpg"
const char *imageOUT="imgeout.jpg"
CImg<uchar> input_image(imageIN);

 size_t image_width = input_image.width();  
 size_t image_height = input_image.height();
 size_t channels = input_image.spectrum();  
 
  CImg<uchar> output_image(image_width, image_height, input_image.depth(), channels); //create
  
  //pout points to some data
  for(size_t h=0; h<image_height; ++h)         
    for (size_t w=0; w<image_width; ++w) {   
        output_image(w, h, 0, 2) = *pout;     //B
        output_image(w, h, 0, 1) = *(pout+1); //G
        output_image(w, h, 0, 0) = *(pout+2); //R
        pout +=3;                            
    }
    
output_image.save(imageOUT);       //save