Displaying matched Features
I'm trying to create a showMatchedFeatures function similar to that of MATLAB, using OpenCV library in C++. A matchFeatures function has already been made which takes as parameters two features f1...
View ArticleCompute camera height
I have a dataset of images taken by Kinect (RGB+Depth). This dataset is for person detection so I do have the bounding box or/and the skeleton of the person. I need to compute or estimate the height of...
View ArticleRead/extract pixel value of a GeoTiff
Hi there! I'm using Qt with GDAL and OpenCV to convert and display GeoTiffs. Showing works fine, the images open in the opencv popup window and I can pan and zoom around. What I want to do now is click...
View Articlecmake not picking GStreamer on Ubuntu
Hi I want to build opencv with GStreamer support. I built the GStreamer from source (version 1.8.1) following this guide: http://kacianka.at/?p=145 I have 'gstreamer_build' folder at my home directory...
View ArticleProcessing Camera stream in Opencv, pushing it over RTMP (NGINX RTMP Module)...
Output video: https://youtu.be/VxfoBQjoY6E **Explanation:** I want to: Process camera stream in Opencv and push it over to RTMP server. I already have NGINX (RTMP module) set up and I have tested...
View ArticleHow to use keypoints from .txt file (or another structure) in opencv?
I'm using the [Fast SIFT Image Features Library][1], which is incredibly faster than the OpenCV implementation (approx 0.01 sec for keypoints and descriptors computations!). However, the resulting...
View ArticleWhich video extension
I want to save a sequence of images from my Kinect but I thought to record a video and then extract the frames and save them as an image file. What do you prefer saving images or a video? How the video...
View ArticlePatents in OpenCV
Hi all, It was my understanding from previous posts (e.g., [here](http://answers.opencv.org/question/52001/how-to-compile-nonfree-module-in-opencv-30-beta/)) that algorithms that are potentially...
View ArticleCoordinates of keypoints using FLANN matcher
I have two images (faces) and I want to check if it is the same person or not. So far I implemented as it is in [this...
View ArticleMake a condition on OpenCV4Android
Hey Everyone, Im newbie on OpenCV4Android "BlobColorDetection" . I try to knowing the HSV Color from this object with this Toast. My question how to make a condition when Value = 160 - 180 then show...
View ArticleTrouble with Knn
I've build a knn model for regression, but isn't work. When I call for a prediction, with a set of numbers, the answer always be the same value, like this >>> In = 0.742781 || Out =...
View ArticleHow to use np.count_nonzero() within a range of pixels?
Hi there! I am working on a script that reads the non-zero pixels in a binary image. I am using np.count_nonzero() to count non zero pixels, which works fine until, I specify a range of coordinates....
View Articlelkdemo.cpp will not run in OpenCV 3.0
I am able to build lkdemo.cpp in the samples folder of OpenCV 3.0. When I run the code, it displays the video from the webcam, but will not allow me to click and errors out with the following:...
View ArticleCUDA method overhead
I am trying to move some of my processing to the GPU and it is taking much longer than I would expect. Running the NVIDIA profiler, I see that there are large gaps between the segments of work in the...
View ArticleHow to use keypoints from another library to OpenCV?
I'm using the [Fast SIFT Image Features Library][1], which is incredibly faster than the OpenCV implementation (approx 0.01 sec for keypoints and descriptors computations!). This is the code about how...
View ArticleWhy there is no cuda::SIFT_CUDA in Opencv?
Reading Opencv 3.0 documentation I found [cuda::SURF_CUDA][1], which (I think) is the SURF algorithm implementation exploiting nvidia GPUs. I didn't find nothing about a GPU implementation of SIFT...
View ArticleError creating CvSVM in Java with OpenCV 2.4.13
Hello all, I am new to openCV and trying to learn how to write an image recognition application in java. Samples have been tough to find but I am scouring the web. I found an example to train images...
View Articleopencv error: unspecified error (frame window not be created ) in...
Am doing object recognition in video. once the object is identified the particular object will be loaded. after closing the object again camera has to start. it works for four to five times...
View ArticlePython and Wireless IP camera
Is There any way to use ip camera with opencv python default api?? or how can i accept ip camera and take image processing with python
View Articlefacial detection/recognition
Im having a bit of a slow start with openCV and have had some difficulties setting it up and integrating with Qt but am finally in the clear . I would like to know how to detect face in openCV using...
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