Trying to invert an expression

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The discussion revolves around inverting the expression n(k) = ∫ cos(k(x-y)) f(x,y) dxdy to obtain f(x,y). The original poster initially confused the notation and was corrected regarding the inclusion of k in the integral. A participant suggests that the transform resembles a "cosine transform" and provides a resource for further exploration. They also confirm that the inverse Fourier transform could be applicable in this context. The conversation emphasizes the importance of correctly identifying the transform type for successful inversion.
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I've come across an expression that looks like

n(k) = ∫cos(x-y)f(x,y)dxdy

Is there a name for this transform? I would like to invert it to obtain f(x,y) but I'm not used to the 2D integral on the RHS. I tried to turn it into a Fourier transform:

n(k) = 1/2 ( ∫eixe-iyf(x,y)dxdy + ∫e-ixeiyf(x,y)dxdy)

but got stuck. Any help would be appreciated.

Thanks
 
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Hi, there is something of strange, where is ##k## in the integral?, you say ##n(k)## but in the right side I don't see ##k##, and what is the domain of integration ?
 
You are right! Sorry, I forgot about the k when writing down the expression(s). The correct expression is

n(k) = ∫ cos( k(x-y) ) f(x,y) dxdy

Thanks
 
I think your transform is analogous to the ''cosine transform'', I hope you can find something useful here

http://dsp-book.narod.ru/TAH/ch03.pdf

but I think (as you wrote...) it is possible to use the inverse Fourier transform...
 
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