opencv - SURF and OpenSURF to color image -


i using surf features in opencv input images converted gray image. 

 cvtcolor(object, object, cv_rgb2gray);

when went through documentation of opensurf realised not in grayscale.

my confusion can apply surf image formats (yuv, hsv, rgb) or have change , modify program achieve that?

most feature detectors work on greyscale because analyse patterns of edges in image patch. can run surf on single colour channel colour formats mention i.e. can run on y, u or v yuv images, or on h, s or v hsv images. not sure how opensurf treats this, must using greyscale image internally.


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