get RGB pixel values from uint8 c++

Question

I create ac# function that moves BitmapFrame picture to byte[] (using copypixels). Then I paste this buffer into c++ dll where it is uint8*. There is a structure in cpp

typedef struct  
{
    float r;
    float g;
    float b;
} pixel;

Is it possible to organize a loop for this uint8* buffer to get pixel-by pixel (for example by xy - height and width of image(this data I have too))? something like

for(i=0; i< height;i++)
{
for(j=0; j <width;j++)
{
   SomeWorkWithPixelsfromUint8(i,j) //???
}
}

Where SomeWorkWithPixelsfromUint8(i,j) could operate RGB structure

So simple uint8 -> getPixel(x,y) ????

Answer 1

Assuming that your picture data have a layout like this

• Pixels are scanlines per scanlines, left to right
• One pixel is packed as RGB, or eventually RGBA
• You use pixelSize bytes per pixel (might be 3, might be 4 if you alpha channel)

---

uint8_t* picData = ...;

uint8_t* pixel = picData;
for(int i = 0; i < height; ++i) {
  for(int j = 0; j < width; ++j, pixel += pixelSize) {
       float r = pixel[0];
       float g = pixel[1];
       float b = pixel[2];
       // Do something with r, g, b
  }
}

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