iphone opencv - template matching
i've implemented this OpenCV build into my iphone project:

http://aptogo.co.uk/2011/09/opencv-framework-for-ios/


It builds successfully and i know how to capture an image with my camera, grayscale it and show it on an imageview.

But what i'd like to do is templatematching with the image that i captured (with the camera) against an template image.

I have both images grayscaled, but i just don't get how the 'matchTemplate' works. This is what i have so far:

    cv::Mat grayFrame, grayImg, output;
    
    // This is the template image which i store in a cv::Mat and
    // after that i grayscale the image
    UIImage *testImage = [UIImage imageNamed:@"qr.png"];
    cv::Mat tempMat = [testImage CVMat];
    cv::cvtColor(tempMat, grayImg, cv::COLOR_RGB2GRAY);


    // Convert captured frame to grayscale
    cv::cvtColor(_lastFrame, grayFrame, cv::COLOR_RGB2GRAY);
    
    // Having trouble here...
    cv::matchTemplate(grayFrame, grayImg, output, CV_TM_CCORR_NORMED);
    

    // Display result
    // This already works for both the captured image and the template image
    camView.image = [UIImage imageWithCVMat:grayFrame];


The problem with this code is, is this line:

cv::matchTemplate(grayFrame, grayImg, output, 1);

I'm not sure if i'm doing it right. Because i don't get a result back in 'output' like "MinMax" to get the positions of the found match... Am i even passing the right variables to the matchTemplate function...??

Anyway, can someone please tell me what i'm doing wrong and how to make this work?


Thanks for any help!
iphone opencv - template matching
===

i've implemented this OpenCV build into my iphone project:

http://aptogo.co.uk/2011/09/opencv-framework-for-ios/


It builds successfully and i know how to capture an image with my camera, grayscale it and show it on an imageview.

But what i'd like to do is templatematching with the image that i captured (with the camera) against an template image.

I have both images grayscaled, but i just don't get how the 'matchTemplate' works. This is what i have so far:

    cv::Mat grayFrame, grayImg, output;
    
    // This is the template image which i store in a cv::Mat and
    // after that i grayscale the image
    UIImage *testImage = [UIImage imageNamed:@"qr.png"];
    cv::Mat tempMat = [testImage CVMat];
    cv::cvtColor(tempMat, grayImg, cv::COLOR_RGB2GRAY);


    // Convert captured frame to grayscale
    cv::cvtColor(_lastFrame, grayFrame, cv::COLOR_RGB2GRAY);
    
    // Having trouble here...
    cv::matchTemplate(grayFrame, grayImg, output, CV_TM_CCORR_NORMED);
    

    // Display result
    // This already works for both the captured image and the template image
    camView.image = [UIImage imageWithCVMat:grayFrame];


The problem with this code is, is this line:

cv::matchTemplate(grayFrame, grayImg, output, 1);

I'm not sure if i'm doing it right. Because i don't get a result back in 'output' like "MinMax" to get the positions of the found match... Am i even passing the right variables to the matchTemplate function...??

Anyway, can someone please tell me what i'm doing wrong and how to make this work?


Thanks for any help!