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2014-12-09 13:51:02 -0500 marked best answer Template Matching for android is rather slow. Need suggestions for faster and more user friendly interface.

I have developed the application for android to find the overlap by means of "template matching" method. But the problemis that it is really slow.

Can anybody help me to make it more faster and User-friendly?


2014-12-09 13:50:17 -0500 marked best answer Skipping frame in android-openCV application

I want to process evry 3 input frame from camera on my android-openCV application. my frames have Mat format and I am using "CameraBridgeViewBase". On the other words, I want to skip some frame without processing.

Can anybody help me?


2014-12-09 13:49:57 -0500 marked best answer The projects are out of date!! (Visual Studio 2010 Express+OpenCV 2.4.0)

When I want to debug the *.sln fine (generated by Cmake) in Visual Studio 2010, I come accross this problem:

The projects are out of date :

ZERO_CHECK - Debug Win32 zlib - Debug Win32 opencv_core - Debug Win32 libjasper - Debug Win32 opencv_imgproc - Debug Win32 libtiff - Debug Win32 libpng - Debug Win32 libjpeg - Debug Win32 opencv_flann - Debug Win32 opencv_highgui - Debug Win32

Would you like to build them?

After clicking "Yes".... the are the error with that:

'....\lib\Debug\opencv_gpu240d.lib' 6>LINK : fatal error LNK1104: cannot open file '....\lib\Debug\opencv_gpu240d.lib' 5>LINK : fatal error LNK1104: cannot open file '....\lib\Debug\opencv_gpu240d.lib' 4>LINK : fatal error LNK1104: cannot open file '....\lib\Debug\opencv_gpu240d.lib' 7>LINK : fatal error LNK1104: cannot open file '....\lib\Debug\opencv_gpu240d.lib' 8>LINK : fatal error LNK1104: cannot open file '....\lib\Debug\opencv_gpu240d.lib'

Would you plaese help me with that?!!


2014-12-09 13:49:57 -0500 marked best answer Resolution and Focal lengths menu in OpenCV-Android Application

Hi Friends,

I need to use the special resolution range menu and also focal lengths to control the OpenCV camera in my android application.

When I use "getResolutionList()" , the maximum resolution is "1280-by-720", but I need "1948-by-1488" as a minimum resolution in my menu. What should I do to solve this problem?

Also, how can I adjust the "Focal Lengths" (zoom) option in my application.

Thanks in advance.

2014-12-09 13:49:24 -0500 marked best answer Can't setup NDK for Eclipse+OpenCV4Android

Hi friends,

I have a big problem with installing NDK and openCV in linux for my Eclipse+Android SDK and also the home page of andrroid NDK is so unclear for me. can somebody help me please?!!!!

2014-12-09 13:49:23 -0500 marked best answer buildPyramid command for android

Hi Friends,

I need to use android version of "buildPyramid" to make the pyramid images but I can not find it.

Please help me.


2014-12-09 13:47:58 -0500 marked best answer Resolution and camera calibration

Hey guys, I have a conceptual problem in the field of camera calibration.

If I reduce the resolution of images(the chessboard images and the images that should aplly to algorithm for final results), the calibration algorithm works normally?


2014-12-09 13:47:27 -0500 marked best answer Android and OpenCV

hi guys, I want to use the openCV in Android for an application, can I write it in C++ or I have to use Java for that?

Thanks for Help

2014-12-09 13:41:32 -0500 marked best answer MSVisual C++ 2010 express and OpenCV

Hi Every body, I have installed openCV on Visual C++ 2010 express, my OS is windows XP and the problem is that it can not compile my program!!!

The errors are :

'backtopeoj.exe': Loaded 'C:\Dokumente und Einstellungen\Administrator\Eigene Dateien\Visual Studio 2010\Projects\backtopeoj\Debug\backtopeoj.exe', Symbols loaded.
'backtopeoj.exe': Loaded 'C:\WINDOWS\system32\ntdll.dll', Symbols loaded (source information stripped).
'backtopeoj.exe': Loaded 'D:\ProgrammFile\OpenCV2.1\bin\cxcore210d.dll', Cannot find or open the PDB file
LDR: LdrpWalkImportDescriptor() failed to probe D:\ProgrammFile\OpenCV2.1\bin\cxcore210d.dll for its manifest, ntstatus 0xc0150002
Debugger:: An unhandled non-continuable exception was thrown during process load
The program '[2640] backtopeoj.exe: Native' has exited with code -1072365566 (0xc0150002).

Would you please help me with that?


2014-12-09 13:16:17 -0500 marked best answer Converting .Mat to CvArr format (JavaCV)

I wnat to use cvRectangle() in Javacv and the first parameter is the current frame of camera. But the problem is that format of the frames are .Mat and I need to convert them to CvArr format to use on this command for my android application (Template Matching android-OpenCv application).

How can I do the conversion?

Please help me with that.


her is my code:

public void overlapFinder( String inputPath )//inputhpath is the template image path to load

//mRgba is the current frame in Mat format

    // to find the best overlap in the current frame with template image

    CvPoint minloc = new CvPoint(0,0) ;
    CvPoint maxloc = new CvPoint(0,0);

    double minval, maxval;

    Mat     mResult; 

    mTemplate = Highgui.imread(inputPath);

    int resultWidth =  mRgba.width() - mTemplate.width() + 1; 

    int resultHeight = mRgba.height() - mTemplate.height() + 1;

    mResult = new Mat (resultHeight, resultWidth, CvType.CV_32F);

    //cvMinMaxLoc( mResult, minval, maxval, minloc, maxloc, 0 );

    IplImage destImage = mRgba;

    cvRectangle(mRgba, cvPoint( minloc.x(), minloc.y()),
            cvPoint( minloc.x() + mTemplate.width(), minloc.y() + mTemplate.height()),
            cvScalar( 0, 0, 255, 0 ), 1, 0, 0 );        

    Imgproc.matchTemplate(mRgba, mTemplate , mResult , Imgproc.TM_CCOEFF) ; 

    Core.MinMaxLocResult result = Core.minMaxLoc(mResult);

    double maxVal = result.maxVal;
2014-12-09 13:16:08 -0500 marked best answer Saving High Quality Image

In my Android-OpenCV application, I am saving the Image with ".JPG" extention. they are 1056-by-704 and are acceptable but quality is not good and the image is not sharp enough for processing.

It is the format of saved matrix as image : Mat(height, width, CvType.CV_32FC4)

Can I save them with better quality? If no!! does anybody have idea to make the image more shorp with better quality?


2014-10-27 14:38:13 -0500 received badge  Popular Question (source)
2014-07-21 11:32:29 -0500 marked best answer Image Stitching with OpenCV

hey guys, do you know that openCV can do the image stitching? if yes, does it have limitation to perform that?


2013-06-18 07:23:49 -0500 marked best answer Resizing Image

Does anyone know how I can resize my image to the exact size by OpenCV( Decreasing resolution)? thanks for help

2013-05-29 00:33:54 -0500 answered a question How to install OpenCV Manager on emulator

This Link will solve your problem to install the OpenCV Manager Package on emulator.

2013-05-29 00:30:15 -0500 answered a question How to install OpenCV Manager on emulator

If you are using eclipse:

Right click on the name of project choose Run AS->Run Configuration->Target and choose the AVD as the target that you want to use.

2013-05-23 06:16:05 -0500 answered a question Help in using pattern recognition with open cv

This Link will help you :)

2013-05-23 00:22:07 -0500 answered a question Camera calibration - getting bad rectified image

Maybe the problem is the size of your images. The images (Chessboard Images) that you use to calculate calibration matrixes should have the same size with the images that you want to calibrate.

2013-05-16 00:01:18 -0500 commented question OpenCV Machtching Feature

Dear Notas,

About Ordering:

When the images are applied to the "stitching_detailed.cpp" as the arguments, the "matcher(features, pairwise_matches)" function try to find matches between all images and choose the best mached image for image number x. This procedure is done for all input images(compare it with all other input images to find the best match).

I know that each input image in my algorithm has the best match with the image in next, I mean "image i" with "image i+1" and so on. So I want to skip comparing "image i" with all images except "image i+1". Because I know that they are in right order(The photos sequentially taken) the best matches for each image is the next one, so it is not neccessary to compare it with all inputs. It is exactly the problem that I have.

2013-05-15 13:52:50 -0500 commented question OpenCV Machtching Feature

Hi Notas,

Maybe my question is not clear, but as you said, I need to compare the image just with the next image. I am confused right now. Would you please tell more in detail.

2013-05-15 04:12:25 -0500 asked a question OpenCV Machtching Feature

The function matcher(features, pairwise_matches) in OpenCV, suppose that the input images are not in order, so it tries to find the right order by processing the features and compare one image with others.

It waste too much time for many input images like 20. The pairwise_matches is 400 for 20 input images. I want to insert the images in the right order to avoid comparing one with all others (just with the next one and reduce the pairwise_matches from 400 to 19 !!!).

How can I implement it?!!

Thanks in Advance

2013-05-14 01:01:35 -0500 commented answer How to speed up multiple object detection and tracking?

Your welcome Man ..For the concurrency I do not have idea now. If the answer is useful, just mark it as a correct answer for the others :)

2013-05-14 00:00:17 -0500 answered a question How to speed up multiple object detection and tracking?

Image Pyramid method can help you to manage this problem. This Link is about the fast template matching by means of Image Pyramid.

Hope the idea be usefull.

2013-05-12 23:44:36 -0500 answered a question what i should learn before learning opencv

Of course you need to read something about image processing and computer vision. My suggestion is THIS BOOK.

Good Luck Man :)

2013-05-12 10:53:28 -0500 commented answer Problem with OpenCV calibration module

Well, I dont have any idea about it right now, my friend.

2013-05-08 02:11:24 -0500 answered a question Does the matching work in OpenCV 2.4.4?

If you show the matches in one window, you can see that sometimes one feature point from first or second image is matched to more than one point in the other image. So, you will have more matches than 241.