Discrete Fourier Transform (Discrete Fourier Transform)

Core functions:

Cvdft

Program:

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Code:

# Include "CV. H "# include" cxcore. H "# include" highgui. H "# include <iostream> int DFT (INT argc, char ** argv) // Discrete Fourier Transform (discrete Fourier transform, abbreviated as DFT) {iplimage * src = cvloadimage ("E: \ picture \ 4.jpg", 0); iplimage * src32f = cvcreateimage (cvgetsize (SRC), ipl_depth_32f, 1 ); iplimage * src32f_one = cvcreateimage (cvgetsize (SRC), ipl_depth_32f, 1); iplimage * dst32f = cvcreateimage (cvgetsize (SRC), ipl_depth_32f, 1 ); iplimage * dst32f_one = cvcreateimage (cvgetsize (SRC), ipl_depth_32f, 1); iplimage * dst2_32f = cvcreateimage (cvgetsize (SRC), ipl_depth_32f, 1 ); iplimage * dst2_32f_one = cvcreateimage (cvgetsize (SRC), ipl_depth_32f, 1); iplimage * src232f = cvcreateimage (cvgetsize (SRC), ipl_depth_32f, 1 ); iplimage * DST = cvcreateimage (cvgetsize (SRC), 8, 1); iplimage * src2 = cvcreateimage (cvgetsize (SRC), 8, 1); cvzero (src32f); cvzero (dst32f ); // convert uchar to the 32f type for normalization and calculation conversion cvconvertscale (SRC, src32f); // normalization process [0,255] Double minval = 0; double maxval = 0; cvminmaxloc (src32f, & minval, & maxval); double min = minval; double max = maxval; double scale = 255/(maxval-minval); double shift =-minval * scale; cvconvertscale (src32f, src32f_one, scale, shift); cvminmaxloc (src32f_one, & minval, & maxval); STD: cout <minval <maxval <STD: Endl; // Fourier transform cvdft (src32f_one, dst32f, cv_dxt_forward); // normalize the Fourier transform results [0,255] minval = 0; maxval = 0; cvminmaxloc (dst32f, & minval, & maxval); Scale = 255/(maxval-minval); shift =-minval * scale; cvconvertscale (dst32f, dst32f_one, scale, shift ); // convert the normalized Fourier Transformation Result to eight bits to display cvconvertscale (dst32f_one, DST); cvminmaxloc (dst32f_one, & minval, & maxval); STD :: cout <"def result minval:" <minval <"maxval:" <maxval <STD: Endl; // Fourier inverse cvdft (dst32f, dst2_32f, cv_dxt_inverse); // normalized Fourier inverse transformation result [0,255] minval = 0; maxval = 0; cvminmaxloc (dst2_32f, & minval, & maxval ); scale = 255/(maxval-minval); shift =-minval * scale; cvconvertscale (dst2_32f, dst2_32f_one, scale, shift); // restore the source image, inverse normalization scale = (max-min)/255; // normalization is first multiplied and then added, and restoration is first added and then multiplied, so shift must be equal to Min rather than min * scaleshift = min; cvconvertscale (dst2_32f_one, src232f, scale, shift); // convert the restored image to an 8-bit cvconvertscale (src232f, src2); cvnamedwindow ("src "); cvnamedwindow ("DST"); cvnamedwindow ("src2"); cvshowimage ("src", Src); cvshowimage ("DST", DST); cvshowimage ("src2 ", src2); cvwaitkey (0); cvdestroywindow ("src"); cvdestroywindow ("DST"); cvdestroywindow ("src2"); cvreleaseimage (& SRC ); cvreleaseimage (& DST); cvreleaseimage (& src32f); cvreleaseimage (& dst32f); cvreleaseimage (& src2); cvreleaseimage (& src32f_one); cvreleaseimage (& dst32f_one ); cvreleaseimage (& dst2_32f_one); Return 0 ;}

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