RGB亮度调节，Delphi实现图像RGB亮度调节，像PhotoShop那样调整图像的亮度。对每个象素点的R、G、B分量进行调节，不能越界，限制在0～255。

-The RGB brightness adjustment, Delphi to achieve the image RGB brightness adjustment as to adjust the brightness of the image, such as PhotoShop. For each pixel, R, G, and B component is adjusted, not bounds restricted to 0 ~ 255.