im_process_glo.h
Go to the documentation of this file.00001 /** \file
00002 * \brief Image Processing - Global Operations
00003 *
00004 * See Copyright Notice in im_lib.h
00005 * $Id: Exp $
00006 */
00007
00008 #ifndef __IM_PROCESS_GLO_H
00009 #define __IM_PROCESS_GLO_H
00010
00011 #include "im_image.h"
00012
00013 #if defined(__cplusplus)
00014 extern "C" {
00015 #endif
00016
00017
00018
00019 /** \defgroup transform Domain Transform Operations
00020 * \par
00021 * FFT, Wavelts, Hough, Distance.
00022 * \par
00023 * FFTW Copyright Matteo Frigo, Steven G. Johnson and the MIT. \n
00024 * http://www.fftw.org \n
00025 * See fftw.h or fftw3.h
00026 * \par
00027 * Must link with "im_fftw.lib" for FFTW version 2.1.5, and "im_fftw3.lib" for version 3.0.1. \n
00028 * Both libraries are available because version 3 was not that fast from version 2,
00029 * and its file size is 3x bigger than version 2. But version 3 was not compiled using hardware
00030 * otimizations.
00031 * \par
00032 * The FFTW lib has a GPL license. The license of the "im_fftw.lib" library is automatically the GPL.
00033 * So you cannot use it for commercial applications without contacting the authors.
00034 * \par
00035 * See \ref im_process_glo.h
00036 * \ingroup process */
00037
00038 /** Forward FFT. \n
00039 * The result has its lowest frequency at the center of the image. \n
00040 * This is an unnormalized fft. \n
00041 * Images must be of the same size. Destiny image must be of type complex.
00042 * \ingroup transform */
00043 void imProcessFFT(const imImage* src_image, imImage* dst_image);
00044
00045 /** Inverse FFT. \n
00046 * The image has its lowest frequency restored to the origin before the transform. \n
00047 * The result is normalized by (width*height). \n
00048 * Images must be of the same size and both must be of type complex.
00049 * \ingroup transform */
00050 void imProcessIFFT(const imImage* src_image, imImage* dst_image);
00051
00052 /** Raw in-place FFT (forward or inverse). \n
00053 * The lowest frequency can be centered after forward, or
00054 * can be restored to the origin before inverse. \n
00055 * The result can be normalized after the transform by sqrt(w*h) [1] or by (w*h) [2],
00056 * or left unnormalized [0]. \n
00057 * Images must be of the same size and both must be of type complex.
00058 * \ingroup transform */
00059 void imProcessFFTraw(imImage* src_image, int inverse, int center, int normalize);
00060
00061 /** Auxiliary function for the raw FFT. \n
00062 * This is the function used internally to change the lowest frequency position in the image. \n
00063 * If the image size has even dimensions the flag "center2origin" is useless. But if it is odd,
00064 * you must specify if its from center to origin (usually used before inverse) or
00065 * from origin to center (usually used after forward). \n
00066 * Notice that this function is used for images in the the frequency domain. \n
00067 * Image type must be complex.
00068 * \ingroup transform */
00069 void imProcessSwapQuadrants(imImage* src_image, int center2origin);
00070
00071 /** Hough Lines Transform. \n
00072 * It will detect white lines in a black background. So the source image must be a IM_BINARY image
00073 * with the white lines of interest enhanced. The better the threshold with the white lines the better
00074 * the line detection. \n
00075 * The destiny image must have IM_GRAY, IM_INT, width=180, height=2*rmax+1, where rmax is the image diagonal/2. \n
00076 * The houfh transform defines "cos(theta) * X + sin(theta) * Y = rho" and the parameters are in the interval: \n
00077 * theta = "0 .. 179", rho = "-height/2 .. height/2" .\n
00078 * Returns zero if the counter aborted. \n
00079 * Inspired from ideas in XITE, Copyright 1991, Blab, UiO \n
00080 * http://www.ifi.uio.no/~blab/Software/Xite/
00081 * \ingroup transform */
00082 int imProcessHoughLines(const imImage* src_image, imImage* dst_image);
00083
00084 /** Draw detected hough lines. \n
00085 * The source image must be IM_GRAY and IM_BYTE. The destiny image can be a clone of the source image or
00086 * it can be the source image for in place processing. \n
00087 * The hough points image is a hough transform image that was thresholded to a IM_BINARY image,
00088 * usually using a Local Max threshold operation. Again the better the threshold the better the results. \n
00089 * The destiny image will be set to IM_MAP, and the detected lines will be drawn using a red color. \n
00090 * Returns the number of detected lines.
00091 * \ingroup transform */
00092 int imProcessHoughLinesDraw(const imImage* src_image, const imImage* hough_points, imImage* dst_image);
00093
00094 /** Calculates the Cross Correlation in the frequency domain. \n
00095 * CrossCorr(a,b) = IFFT(Conj(FFT(a))*FFT(b)) \n
00096 * Images must be of the same size and only destiny image must be of type complex.
00097 * \ingroup transform */
00098 void imProcessCrossCorrelation(const imImage* src_image1, const imImage* src_image2, imImage* dst_image);
00099
00100 /** Calculates the Auto Correlation in the frequency domain. \n
00101 * Uses the cross correlation.
00102 * Images must be of the same size and only destiny image must be of type complex.
00103 * \ingroup transform */
00104 void imProcessAutoCorrelation(const imImage* src_image, imImage* dst_image);
00105 /** Calculates the Distance Transform of a binary image
00106 * using an aproximation of the euclidian distance.\n
00107 * Each white pixel in the binary image is
00108 * assigned a value equal to its distance from the nearest
00109 * black pixel. \n
00110 * Uses a two-pass algorithm incrementally calculating the distance. \n
00111 * Source image must be IM_BINARY, destiny must be IM_FLOAT.
00112 * \ingroup transform */
00113 void imProcessDistanceTransform(const imImage* src_image, imImage* dst_image);
00114
00115 /** Marks all the regional maximum of the distance transform. \n
00116 * source is IMGRAY/IM_FLOAT destiny in IM_BINARY. \n
00117 * We consider maximum all connected pixel values that have smaller pixel values around it.
00118 * \ingroup transform */
00119 void imProcessRegionalMaximum(const imImage* src_image, imImage* dst_image);
00120
00121
00122 #if defined(__cplusplus)
00123 }
00124 #endif
00125
00126 #endif