how to find spatial frequency of color image

i have fused two images and now i want to find the spatial frequency of fused image can anyone please help

Answer 1

[Image Analyst]

You can calculate the 2D FFT of an image. The image must be a 2D image, not a 3D color image. So you can convert that to gray scale using rgb2gray(), or you can use the red, green, or blue channel, or you can convert to another colorspace such as lab or hsv (using rgb2hsv() function) and then do the FFT of the h, s, or v channel. It all depends on what you want to do with the information once you get it.

[mohammad shafi bhatt]

thanks i have to compare the images .As i am fusing the images to get resultant image ,i want to compare their spatial frequency in order to check the performance the the fusion algorithm

[Image Analyst]

You're welcome. There are other ways to compare images also, such as histograms, SSIM, etc.

[mohammad shafi bhatt]

CAN U PLEASE SEND ME THE CODE FOR FINDING SPATIAL FREQUENCY AND FUSION MUTUAL INFORMATION OF IMAGE PLZ ITZ URGENT THANKS WITH GREAT REGARDS

[Image Analyst]

I said you can use fft2() to get the spatial frequencies. I don't know what "fusion mutual information" is.

Answer 2

[Jan]

You probably want to analyze the structure of the image's 2d fourier transform using fft2(). Either for each channel or after conversion to a gray image.

[mohammad shafi bhatt]

actually i have to calculate for each channel