Mercurial > cortex

     1 #+title: Fun with Gabor Filters

     2 #+author: Robert McIntyre

     3 #+email: rlm@mit.edu

     4 #+description: gabor filters in clojure with opencv

     5 #+keywords: computer vision, jMonkeyEngine3, clojure, opencv

     6 #+SETUPFILE: ../../aurellem/org/setup.org

     7 #+INCLUDE: ../../aurellem/org/level-0.org

     8 #+babel: :mkdirp yes :noweb yes :exports both

     9 

    10 

    11 

    12 #+name: gabor

    13 #+begin_src clojure

    14 (ns cortex.gabor

    15   (:import org.opencv.core.CvType)

    16   (:import java.awt.image.BufferedImage)

    17   (:import ij.ImagePlus)

    18   (:import org.opencv.core.Mat)

    19   (:use cortex.sense)

    20   (:use cortex.util)

    21   )

    22 

    23 (defn load-opencv

    24   "Load the opencv native library. Must be called before any OpenCV

    25   stuff is used."

    26   []

    27   (clojure.lang.RT/loadLibrary "opencv_java249"))

    28 

    29 (defn make-kernel []

    30   (let [r (org.opencv.core.Mat. 5 5 CvType/CV_32F)]

    31     (.put r 0 0 (float-array (map (fn [_] (rand)) (range 25))))

    32     (println (.dump r))

    33 

    34     ;;r

    35 

    36     (org.opencv.core.MatOfFloat. (float-array [0.5]))

    37     ))

    38 

    39 (defn gabor-kernel [sigma aspect-ratio theta wavelength phase-offset]

    40   

    41   ;; first, find the size of the kernel which is required

    42   (let [square #(expt % 2)

    43         rotated (fn [[x y]]

    44                   [(+ (* x (Math/cos theta)) (* y (Math/sin theta)))

    45                    (- (* y (Math/cos theta))  (* x (Math/sin theta)))])

    46                              

    47         gaussian (fn [[x y]]

    48                    (let [[x' y'] (rotated [x y])]

    49                      (Math/exp (- (/ (+ (square x')

    50                                         (square (* aspect-ratio y')))

    51                                    (* 2 (square sigma)))))))

    52         sinusoid (fn [[x y]]

    53                    (let [[x' y'] (rotated [x y])]

    54                      (Math/cos

    55                       (+ (* 2 Math/PI (/ x' wavelength))

    56                          phase-offset))))

    57 

    58         half-width (max

    59                     (int (* 5 (/ sigma aspect-ratio)))

    60                     (int (* 5 sigma))

    61                     (int (* 5 (/ aspect-ratio sigma))))

    62 

    63         grid (let [axis (range (- half-width) (inc half-width))]

    64                (for [y (reverse axis) x axis] (vector x y)))

    65 

    66         scale (reduce + (map gaussian grid))

    67         

    68         gabor (fn [[x y :as coord]]

    69                 (* (sinusoid coord) (gaussian coord) scale))

    70 

    71         mat-width (+ 1 (* 2 half-width))

    72         mat (Mat. mat-width mat-width CvType/CV_32F)]

    73 

    74     

    75     (.put mat 0 0 (float-array (map gabor grid)))

    76     mat

    77 

    78     ;;(map gabor grid)

    79     

    80     ))

    81 

    82 

    83 (defn show-kernel [kernel]

    84   (let [output "/home/r/proj/cortex/tmp/kernel.png"]

    85     (org.opencv.highgui.Highgui/imwrite output kernel)

    86     (view (ImagePlus. output))))

    87 

    88 (defn print-kernel [kernel]

    89   (println (.dump kernel)))

    90                            

    91 

    92         

    93                       

    94         

    95         

    96         

    97   

    98 

    99 

   100 (defn convolve-practice []

   101   (let [input "/home/r/proj/cortex/images/dominos.jpg"

   102         

   103         

   104         output "/home/r/ppp.png"

   105 

   106         i (org.opencv.highgui.Highgui/imread input)

   107 

   108         kernel (make-kernel)

   109 

   110         new-mat (Mat.)

   111                 

   112         ]

   113 

   114     (org.opencv.imgproc.Imgproc/filter2D  i new-mat CvType/CV_32F (make-kernel))

   115     

   116     (org.opencv.highgui.Highgui/imwrite "/home/r/ppp.png" new-mat)

   117     

   118     (view (ImagePlus. input))

   119     (view (ImagePlus. output))

   120         

   121     ))

   122 

   123   

   124 

   125 

   126 

   127 

   128 

   129 (comment

   130   ;; these work

   131   (def i (org.opencv.highgui.Highgui/imread

   132           "/home/r/proj/cortex/images/dominos.jpg"))

   133   

   134   (org.opencv.highgui.Highgui/imwrite "/home/r/ppp.png" i)

   135 )

   136 #+end_src

   137 

   138 

   139 

   140 * COMMENT Generate Source

   141 #+begin_src clojure :tangle ../src/cortex/gabor.clj

   142 <<gabor>>

   143 #+end_src
author	Robert McIntyre <rlm@mit.edu>
date	Thu, 07 Mar 2013 02:37:49 +0000
parents	b72fea69b2e1
children	fc5bb270596a