convertion of 64 coefficients into 12 coefficients

hi.. i want to extract the color feature.. for that i m using color layout descriptor.. in this process i had find the 64 dct coefficients for each Y, Cb,Cr color space... now in my paper they recommended to use 12 coeffients.. 6 for Y and 3 for Cb,Cr... how can convert like this... please help me with matlab codes...

thanks in advance..

Answer 1

[Walter Roberson]

reduced_Y_dct = y_dct(1:6);

[jenifer]

sir they mentioned " first few coefficients are non linearly quantized using 64 and 32 for DC and AC coefficients"..

[Walter Roberson]

I do not see the relevance of that. You asked how to reduce down to 6 coefficients for Y and I showed you. If you want to reduce to a particular number of DC coefficients and a particular number of AC coefficients, then say so, and indicate which variables the DC and AC coefficients are stored in.

Answer 2

[Elad]

http://imageprocessingblog.com/color-reduction-using-k-means-clustering/

Change the code such that you choose the number of coefficients (clusters) you want for each color plane.