Phase Information

[gowribala]

Hi..

My aim is to extract the phase information in images,but i dont have idea about the phase information.

I searched many documents to understand the phase information,but they are very complicated to understand.

please any one explain or give any URL for understanding of phase information in image.

[fmw42]

convert image -fft result_%d.png

result_0.png is the magnitude image that needs to be processed by -evaluate log 100000 to see anything.

result_1.png is the phase image


see
http://www.fmwconcepts.com/imagemagick/ ... urier.html

[gowribala]

Thanks for your reply....

I choose gabor filter for extracting phase information,but i dont know whether gabor filter is applied in spatial domain or frequency domain.

please guide me how can i use gabor filter...

[fmw42]

Sorry I do not know anything about the Gabor filter. Do you have a reference?

[fmw42]

According to http://mplab.ucsd.edu/tutorials/gabor.pdf and http://en.wikipedia.org/wiki/Gabor_filter, the gabor filter can be constructed in either the spatial or frequency domains. In the spatial domain, it is the product of a Gaussian function with a complex sinusoid function. It is a windowed (by the Gaussian) complex sinusoid. Thus it is a tapered complex sinusoid.

Its use is to identify regions of a given frequency and orientation. One application is to segment an image of various texture patterns. See http://www.cse.iitm.ac.in/~sdas/vplab/c ... r_filt.pdf. Imagemagick does not currently have a Gabor filter function.

Applications usually ignore the phase and look more to the magnitude to get a measure of energy.