How do I determine if I've loaded a greyscale image

SDL Development
1

Hi, can somebody tell me how I can determine if the
image that I’ve loaded into an SDL_Surface is
greyscale or not. My intention is to load color images
into OpenGL using GL_RGBA and use something else for
greyscale (such as GL_LUMINANCE_ALPHA).

Thanks__________________________________
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2

Analyze each pixel to see if the value of R == G == B. To get the pixel
value of an image, use getpixel() found here:

http://sdldoc.csn.ul.ie/guidevideo.php#AEN112

And Suface->w and Surface->h tells the size of the image.

-MarkOn Fri, 12 Dec 2003, Eric Wing wrote:

Hi, can somebody tell me how I can determine if the
image that I’ve loaded into an SDL_Surface is
greyscale or not. My intention is to load color images
into OpenGL using GL_RGBA and use something else for
greyscale (such as GL_LUMINANCE_ALPHA).

Thanks

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