ImageGear for C and C++ on Windows v19.1 - Updated
24-bit RGB Images
User Guide > Concepts > Understanding Bitmap Images > 24-bit RGB Images

24-bit RGB images are images in which each pixel is represented by three 8-bit quantities (thus, 24 bits total) specifying the intensities of red, green, and blue that form the color for the pixel. For example, a pixel that is to be displayed as brightest magenta-magenta being a color formed of equal intensities of red and blue, and no green-would be represented by three bytes having the respective values of 255, 0, 255 for the red, green, and blue intensities. In RGB representation the brightest white would be (255, 255, 255) and black would be (0, 0, 0).