Source Code for Module pycv.cs.cv.imageview

  1  # PyCV - A Computer Vision Package for Python Incorporating Fast Training of Face Detection 
  2   
  3  # Copyright 2007 Nanyang Technological University, Singapore. 
  4  # Authors: Minh-Tri Pham, Viet-Dung D. Hoang, and Tat-Jen Cham. 
  5   
  6  # This file is part of PyCV. 
  7   
  8  # PyCV is free software: you can redistribute it and/or modify 
  9  # it under the terms of the GNU General Public  
 10  # License as published by the Free Software Foundation, either version  
 11  # 3 of the License, or (at your option) any later version. 
 12   
 13  # PyCV is distributed in the hope that it will be useful, 
 14  # but WITHOUT ANY WARRANTY; without even the implied warranty of 
 15  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 16  # GNU General Public License for more details. 
 17   
 18  # You should have received a copy of the GNU General Public License 
 19  # along with this program.  If not, see <http://www.gnu.org/licenses/>. 
 20   
 21  # --------------------------------------------------------------------- 
 22  #!/usr/bin/env python 
 23   
 24   
 25  __all__ = ['ImageView'] 
 26   
 27  from math import sin, cos 
 28  from numpy import array, zeros 
 29   
 30  from pycv.interfaces.opencv import CvPoint2D32f, CV_64FC1, cvGetAffineTransform, \ 
 31      cvWarpAffine, cvCreateMat, cvReleaseMat, CV_INTER_LINEAR, \ 
 32      CV_WARP_FILL_OUTLIERS, cvSetIdentity, CvScalar, cvGetReal2D, \ 
 33      cvSetReal2D 
 34   
 35  from pycv.ext import imageview_transform_pairs, imageview_slide 
 36   
 37 -class ImageView: 
 38      """A rotated rectangular view of an image. 
 39   
 40      :Parameters: 
 41          iparam : array((3,),'i') 
 42              iparam[0] : width of the output patch 
 43              iparam[1] : height of the output patch 
 44              iparam[2] : flipping flag 
 45                  Non-zero if in the view the direction from x-axis to 
 46                      y-axis is counter-clockwise 
 47                  Zero if in the view the direction from x-axis to 
 48                      y-axis is clockwise 
 49          dparam : array((4,),'d') 
 50              dparam[0] : angle of rotation from the image's x-axis to the view's 
 51                  x-axis, clockwise, (in radians) 
 52              dparam[1] : scaling ratio, or the view's one unit length 
 53                  (in image pixels) 
 54              dparam[2] : x-coordinate of the center point (in image pixels) 
 55              dparam[3] : y-coordinate of the center point (in image pixels) 
 56                  the center point of the view on the image is geometrically 
 57                  transformed into location (0.5*w,0.5*h) on the output patch 
 58      """ 
 59   
 60 -    def __init__(self,w = 10,h = 10,x0 = 0,y0 = 0,scale = 1,angle = 0,flip = False): 
 61          """ 
 62          Initialize an image view. 
 63   
 64          :Parameters: 
 65              w : int 
 66                  width of the output patch 
 67              h : int 
 68                  height of the output patch 
 69              x0, y0 : double, double 
 70                  center point, location (x0,y0) on the image is geometrically 
 71                  transformed to location (0.5*w,0.5*h) on the output patch 
 72              scale : double 
 73                  scaling ratio, or the view's one unit length (in image pixel) 
 74              angle : double 
 75                  angle of rotation from the image's x-axis to the view's x-axis, 
 76                  clockwise, (in radian) 
 77              flip : boolean 
 78                  to flip the view's y-axis or not 
 79                  Non-zero if in the view the direction from x-axis to 
 80                      y-axis is counter-clockwise 
 81                  Zero if in the view the direction from x-axis to 
 82                      y-axis is clockwise 
 83          """ 
 84          self.map_matrix = cvCreateMat(2,3,CV_64FC1) 
 85   
 86          self.iparam = array((w,h,flip),'i') 
 87          self.dparam = array((angle, scale, x0, y0),'d') 
 88   
 89 -    def __del__(self): 
 90          cvReleaseMat(self.map_matrix) 
 91           
 92 -    def slide(self, x=0, y=0): 
 93          """Slide the view along its x-axis and y-axis in the image. 
 94           
 95          :Parameters: 
 96              x : double 
 97                  number of (patch) pixels to slide along the x-axis 
 98              y : double 
 99                  number of (patch) pixels to slide along the y-axis 
100                   
101          :Returns: 
102              The dparam array is updated. 
103          """ 
104          imageview_slide(self.iparam, self.dparam, float(x), float(y)) 
105           
106   
107 -    def get_transformation_matrix(self): 
108          A = zeros(6) 
109          B = zeros(6) 
110          imageview_transform_pairs(self.iparam, self.dparam, A, B) 
111          C3 = CvPoint2D32f * 3 
112          src = C3((A[0],A[1]),(A[2],A[3]),(A[4],A[5])) 
113          dst = C3((B[0],B[1]),(B[2],B[3]),(B[4],B[5])) 
114          cvGetAffineTransform(src,dst,self.map_matrix) 
115          return self.map_matrix 
116