One to Many Images by ID
Hello, I am seeking to use 2D features to match a large amount of images. The opencv example of one to many images https://github.com/opencv/opencv/blob/2.4/samples/cpp/matching_to_many_images.cpp So...
View ArticleEXC_BAD_ACCESS while Calculating Descriptor
I try to calculate a SIFT Descriptor out of KeyPoints found by the FAST Corner Detection. For that, I adapted some functions from the...
View ArticleCalculate length between 2 points in c++
I need to calculate length of lines(number of pixels along the path) from a point until a terminal point. terminal point is a point which either ends or which has more than one line starting from that...
View Articlecascade training best practices for lit sign
Was hoping to get some guidance on a few issues... Here is the sign I would like to be able to recognize at night:...
View ArticleGenerate universal static library for iOS
The build script in `platforms/ios/build_framework.py` seems to have no option to generate a static library instead of a framework. I want to embed OpenCV in another framework target, without requiring...
View Articlegstreamer output with VideoWriter?
Hi, is it possible to use VideoWriter to output directly to gstreamer, something like below? It would be a lot simpler than pushing buffers to appsrc, which I can't find any working code for (python,...
View ArticleHow opencv use openmp thread to get performance?
I have installed OpenCV 2.4.13 -D WITH_OPENMP=ON (openmp enable). I want to know built-in functions provided by opencv that use OPENMP so I can show some performance between with openmp and without...
View ArticleH264 encoding
I'm using opencv with ffmpeg to create h264 videos from my opencv project. But the result video is not playable in quicktime or in webbrowser. When i analyse this video with ffmpeg it say: > [mp4 @...
View ArticleConvert from RGB to YUYV in OpenCV
Is there a way to convert from RGB to YUYV (YUY 4:2:2) format? I noted that OpenCV has reverse operation, but not RGB to YUYV for some reason. Maybe someone can point to code which does that (even...
View Articlewhat image format is best for face recognition
I read somewhere on the forum that jpeg's should be avoided. Why is that and what file format would suit it best instead. PNG ?
View Articlecv2.imShow() vs. imShow() within c++ program
To whom it may concern: We build openCV on top of QT5 over Wayland-EGL for Embedded Linux on ARMv7. The cv2.imShow() invoked within python does not work as expected while the imShow() with C++ works...
View ArticleVideo composition by switching between multiple cameras
I wanted to compose a video from multiple cameras. While stitching I wanted to switch view from one camera to another. Is it possible to do it in OpenCv? For example I have 3 video paths(videos having...
View ArticleHow to find the center of a template matching rectangle
I have tried the following template matching OpenCV code. It works well for my application. http://docs.opencv.org/2.4/doc/tutorials/imgproc/histograms/template_matching/template_matching.html I just...
View ArticleChapter4_StructureFromMotion
Hello, I'm trying to use Chapter4_StructureFromMotion example from https://github.com/MasteringOpenCV/code abd its book. I use now opencv 3.1.0 andby compiling that I got...
View ArticleRetrieving the coordinates of pixels identified by SURF
Hi there, I am trying this tutorial here: http://docs.opencv.org/3.0-beta/doc/tutorials/features2d/feature_homography/feature_homography.html It works mildly well when the object I'm looking for is in...
View ArticleProjectPoints not working
I have an image with a disparity map that I reproject to 3D. After running some algorithms to extract the bounding box in 3D, i reprojected each corner back to 2D to find the minimum bounding box but...
View ArticleBuilding for android from cygwin
I am trying to build OpenCV for android as a static library. I went through https://github.com/opencv/opencv/wiki/Building_OpenCV4Android_from_trunk and saw that it mentions cygwin's make is not...
View ArticleOpencv 2.4.9 or Opencv 3.0 for GPU acclerated CUDA
I have installed Opencv 2.4.9 in my Ubuntu machine with CUDA support. But doubtful if Opencv 3.0 only can serve my purpose. I am doing face detection and recognition . Can I go with Opencv 2.4.9 or do...
View ArticleOpencv_contrib PASCAL VOC caffemodel fails
Hey , I am trying to use opencv_contrib with dnn module to use PASCAL VOC caffemodel. I have a set up of, A working Opencv , opencv_contrib along with dnn module . I have used caffe_googlenet.cpp ,...
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