context info - Page 576

Compare images after canny edge detection in OpenCV (C++)

- by typoknig

Hi all, I am working on an OpenCV project and I need to compare some images after canny has been applied to both of them. Before the canny was applied I had the gray scale images populating a histogram and then I compared the histograms, but when canny is added to the images the histogram does not populate. I have read that a canny image can populate a histogram, but have not found a way to make it happen. I do not necessairly need to keep using the histograms, I just want to know the best way to compare two canny images. SSCCE below for you to chew on. I have poached and patched about 75% of this code from books and various sites on the internet, so props to those guys... // SLC (Histogram).cpp : Defines the entry point for the console application. #include "stdafx.h" #include <cxcore.h> #include <cv.h> #include <cvaux.h> #include <highgui.h> #include <stdio.h> #include <sstream> #include <iostream> using namespace std; IplImage* image1= 0; IplImage* imgHistogram1 = 0; IplImage* gray1= 0; CvHistogram* hist1; int main(){ CvCapture* capture = cvCaptureFromCAM(0); if(!cvQueryFrame(capture)){ cout<<"Video capture failed, please check the camera."<<endl; } else{ cout<<"Video camera capture successful!"<<endl; }; CvSize sz = cvGetSize(cvQueryFrame(capture)); IplImage* image = cvCreateImage(sz, 8, 3); IplImage* imgHistogram = 0; IplImage* gray = 0; CvHistogram* hist; cvNamedWindow("Image Source",1); cvNamedWindow("gray", 1); cvNamedWindow("Histogram",1); cvNamedWindow("BG", 1); cvNamedWindow("FG", 1); cvNamedWindow("Canny",1); cvNamedWindow("Canny1", 1); image1 = cvLoadImage("image bin/use this image.jpg");// an image has to load here or the program will not run //size of the histogram -1D histogram int bins1 = 256; int hsize1[] = {bins1}; //max and min value of the histogram float max_value1 = 0, min_value1 = 0; //value and normalized value float value1; int normalized1; //ranges - grayscale 0 to 256 float xranges1[] = { 0, 256 }; float* ranges1[] = { xranges1 }; //create an 8 bit single channel image to hold a //grayscale version of the original picture gray1 = cvCreateImage( cvGetSize(image1), 8, 1 ); cvCvtColor( image1, gray1, CV_BGR2GRAY ); IplImage* canny1 = cvCreateImage(cvGetSize(gray1), 8, 1 ); cvCanny( gray1, canny1, 55, 175, 3 ); //Create 3 windows to show the results cvNamedWindow("original1",1); cvNamedWindow("gray1",1); cvNamedWindow("histogram1",1); //planes to obtain the histogram, in this case just one IplImage* planes1[] = { canny1 }; //get the histogram and some info about it hist1 = cvCreateHist( 1, hsize1, CV_HIST_ARRAY, ranges1,1); cvCalcHist( planes1, hist1, 0, NULL); cvGetMinMaxHistValue( hist1, &min_value1, &max_value1); printf("min: %f, max: %f\n", min_value1, max_value1); //create an 8 bits single channel image to hold the histogram //paint it white imgHistogram1 = cvCreateImage(cvSize(bins1, 50),8,1); cvRectangle(imgHistogram1, cvPoint(0,0), cvPoint(256,50), CV_RGB(255,255,255),-1); //draw the histogram :P for(int i=0; i < bins1; i++){ value1 = cvQueryHistValue_1D( hist1, i); normalized1 = cvRound(value1*50/max_value1); cvLine(imgHistogram1,cvPoint(i,50), cvPoint(i,50-normalized1), CV_RGB(0,0,0)); } //show the image results cvShowImage( "original1", image1 ); cvShowImage( "gray1", gray1 ); cvShowImage( "histogram1", imgHistogram1 ); cvShowImage( "Canny1", canny1); CvBGStatModel* bg_model = cvCreateFGDStatModel( image ); for(;;){ image = cvQueryFrame(capture); cvUpdateBGStatModel( image, bg_model ); //Size of the histogram -1D histogram int bins = 256; int hsize[] = {bins}; //Max and min value of the histogram float max_value = 0, min_value = 0; //Value and normalized value float value; int normalized; //Ranges - grayscale 0 to 256 float xranges[] = {0, 256}; float* ranges[] = {xranges}; //Create an 8 bit single channel image to hold a grayscale version of the original picture gray = cvCreateImage(cvGetSize(image), 8, 1); cvCvtColor(image, gray, CV_BGR2GRAY); IplImage* canny = cvCreateImage(cvGetSize(gray), 8, 1 ); cvCanny( gray, canny, 55, 175, 3 );//55, 175, 3 with direct light //Planes to obtain the histogram, in this case just one IplImage* planes[] = {canny}; //Get the histogram and some info about it hist = cvCreateHist(1, hsize, CV_HIST_ARRAY, ranges,1); cvCalcHist(planes, hist, 0, NULL); cvGetMinMaxHistValue(hist, &min_value, &max_value); //printf("Minimum Histogram Value: %f, Maximum Histogram Value: %f\n", min_value, max_value); //Create an 8 bits single channel image to hold the histogram and paint it white imgHistogram = cvCreateImage(cvSize(bins, 50),8,3); cvRectangle(imgHistogram, cvPoint(0,0), cvPoint(256,50), CV_RGB(255,255,255),-1); //Draw the histogram for(int i=0; i < bins; i++){ value = cvQueryHistValue_1D(hist, i); normalized = cvRound(value*50/max_value); cvLine(imgHistogram,cvPoint(i,50), cvPoint(i,50-normalized), CV_RGB(0,0,0)); } double correlation = cvCompareHist (hist1, hist, CV_COMP_CORREL); double chisquare = cvCompareHist (hist1, hist, CV_COMP_CHISQR); double intersection = cvCompareHist (hist1, hist, CV_COMP_INTERSECT); double bhattacharyya = cvCompareHist (hist1, hist, CV_COMP_BHATTACHARYYA); double difference = (1 - correlation) + chisquare + (1 - intersection) + bhattacharyya; printf("correlation: %f\n", correlation); printf("chi-square: %f\n", chisquare); printf("intersection: %f\n", intersection); printf("bhattacharyya: %f\n", bhattacharyya); printf("difference: %f\n", difference); cvShowImage("Image Source", image); cvShowImage("gray", gray); cvShowImage("Histogram", imgHistogram); cvShowImage( "Canny", canny); cvShowImage("BG", bg_model->background); cvShowImage("FG", bg_model->foreground); //Page 19 paragraph 3 of "Learning OpenCV" tells us why we DO NOT use "cvReleaseImage(&image)" in this section cvReleaseImage(&imgHistogram); cvReleaseImage(&gray); cvReleaseHist(&hist); cvReleaseImage(&canny); char c = cvWaitKey(10); //if ASCII key 27 (esc) is pressed then loop breaks if(c==27) break; } cvReleaseBGStatModel( &bg_model ); cvReleaseImage(&image); cvReleaseCapture(&capture); cvDestroyAllWindows(); }

Search Results

Search found 18993 results on 760 pages for 'context info'.

Page 576/760 | < Previous Page | 572 573 574 575 576 577 578 579 580 581 582 583 | Next Page >

- by typoknig

- by Ceilingfish

- by Garrett

- by Mike McKeown

- by seref

- by Sammy

- by lotuseater

- by Luiscencio

- by TheAggie

- by Luiscencio

- by Damovisa

- by manofseven2

- by Hoang Pham

- by kpower

- by user283266

- by Daniel Baulig

- by Kyle Benzle

- by Laurence

- by arunabha

- by pootow

- by Kelbizzle

- by Miky Mike

- by cre-johnny07

- by arunabha

- by Clinton Bosch

< Previous Page | 572 573 574 575 576 577 578 579 580 581 582 583 | Next Page >