Bounds extraction
I'm currently working on an application that should mark portraits strictly one mark per one portrait. So currently I'm stuck with proper bounding of extracted contours. Here are Canny images. I tried...
View ArticleBrio Capture Settings on Windows
Hullo everyone, I'm trying to capture 720p 60fps video from a Logitech Brio on Windows. This should be a supported format, and it works correctly using OBS, but when I try to set this up using a...
View ArticleAssertion failed (scn + 1 == m.cols) in perspectiveTransform
I am new in Opencv, I want to do Real time object recognition using SURF but I get error about OpenCV Error: Assertion failed (scn + 1 == m.cols) in perspectiveTransform, file...
View ArticleVideoCapture is very slower when opening videoFile why??
**This is a simple code to read Video from File** My problem is that Why when trying to read a Video, the video is very very slower?? I'm trying to read a Video recorded with My Phone thee video file...
View Articleissue with mat::at
This is my code to cfalculate histogram.. void histogram(Mat src,char name[512]) { Mat histg,histb,histr; vectorchannel; split(src,channel); calcHist( &channel[0], 1, 0, Mat(),histg, 1,...
View ArticleNon Maximum Suppression
I am developing multiple ROIs and classifying the existence of an object (object detection). Now I have some fairly overlapping ROIs and want to reduce the number and wanted to use NMS for that. But I...
View ArticleHow to evaluate a cascade classifier?
I used the code of OpenCVBlueprints to plot the pr curve :...
View ArticleFailed to implement lkdemo on iOS
I tried to implement lkdemo's cpp example in iOS, and got reference from [thorrson's lkdemo](https://github.com/manikal/thorrson/blob/master/Thorrson/ViewController.mm). I just use...
View ArticleKeeping count of duration a specific contour is identified
Dear all, I am currently working on a shape identification snippet and need to keep track of the duration of which the particular shape is identified on my screen - i.e. a pseudo confidence level of...
View ArticleHOG-Descriptor malloc freed error
I am trying to calculate the HOGDescriptors for a roi of an image but I am getting the following error: > HOG-Descriptor(34411,0x10618d340)> malloc: *** error for object> 0x106654a98:...
View ArticleFFMPEG and opencv imread
System information (version) OpenCV => 3.3 Operating System / Platform => ubuntu 16.04 Detailed description I extracted frames from a video using ffmpeg.The image format is jpg.The folder...
View ArticleFrequential Analysis in openCV
I am going through a research paper and trying to implement it. In the paper it is saying : That they use the isotrope Gaussian bandwidth Filter, giving a formula and then using the formula they get...
View ArticleBlurring most of each video frame except for ROI - X,Y coordinates known...
I need a way in Python to take a roughly 30 second clip and blur out most of it, except for a circular ROI which would contain the normal video quality. For each frame of the clip I know what the x,y...
View ArticleWidth dissecting with a line on masked image
Dear all, I am currently working with OpenCV 3.2.0 on Python. Suppose I have a colored object that is centered against a white backdrop, and that I've filtered it to produce a B&W image, I wish to...
View ArticleMulti colour detection does not show centroid more than 1 object, Only show...
I am still new to OpenCV, i am currently try to detect object of multiple color as well as center of the object in C++. The color i need to detect is Red, Blue and Yellow. My program able to detect...
View ArticleNeed I to use OCR or other method to recognize special character?
Dear all, I have the following image:  How to recognize these special characters? Thank for supporting!
View ArticleReagarding Faster_RCNN model
Hi All, I am trying to run Faster_rcnn model in opencv with c++. [link text](https://github.com/opencv/opencv/blob/master/samples/dnn/faster_rcnn.cpp) error: The program '[1144] DNN testing.exe' has...
View ArticleExtra delay when copying UMat to Mat
Hello, I am trying to speed up my code using UMats and I encountered the following weird issue: The Code: Mat image = imread("/tmp/lenna_2048.png", IMREAD_COLOR); UMat workMat2 =...
View ArticleopenCV's “minAreaRect ”angle dependent algorithm accuracy
I've noticed that for rectangles with large rotation angles, the "minAreaRect" gives results with better accuracy - when the angle is small, the results have a pixel resolution and when it increases,...
View ArticleConverting RGB into LMS model using C++ and OpenCV
I'm trying to convert image with RGB colorspace into LMS model. The transformation matrix value I got from this [paper](https://arxiv.org/pdf/1711.10662.pdf). I read this [Question : RGB to LMS color...
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