surf

Debug Assertion Failed Expression: _pFirstBlock == pHead using OpenCV and C++ trying to call SurfFeatureDetector

由 梦想的初衷 提交于 2019-12-09 05:46:16
问题 I have this function in C++ using OpenCV: vector<KeyPoint> test(Mat img) { int minHessian = 400; SurfFeatureDetector detector( minHessian ); vector<KeyPoint> vKeypoints; detector.detect( img, vKeypoints ); return vKeypoints; } When I call this function in my main-method everything works fine. int main( int, char** argv ) { // path to a image-file char* input = "image.jpg"; // read image into Mat img Mat img = imread( input, CV_LOAD_IMAGE_GRAYSCALE ); // call function test test(img); waitKey(0

How to match an object within an image to other images using SURF features (in MATLAB)?

由 你离开我真会死。 提交于 2019-12-08 06:32:12
问题 my problem is how to match one image to a set of images and to display the matched images. I am using SURF feature for feature extraction. 回答1: If you have the Computer Vision System Toolbox, take a look at the following examples: Object Detection In A Cluttered Scene Using Point Feature Matching Image Search using Point Features 来源： https://stackoverflow.com/questions/22388481/how-to-match-an-object-within-an-image-to-other-images-using-surf-features-in-m

Opencv 3.0 - module object has no attribute 'xfeatures2d'

由 纵饮孤独 提交于 2019-12-06 18:12:30
问题 I have shifted from OpenCV 2.4.9 to 3.0 to make use of drawMatches and drawMatchesKnn function. I came to know that it does not come along with non-free algorithms like SIFT , SURF. So I installed opencv_contrib from https://github.com/Itseez/opencv_contrib by following steps cmake -DOPENCV_EXTRA_MODULES_PATH=/home/zealous/Downloads/opencv_contrib-master/modules /usr/local .. make -j5 make install I also cross checked in modules of opencv , xfeatures2d was there. Then when I tried to do >>>

Detect spots empty parking OPENCV

由 喜夏-厌秋 提交于 2019-12-06 18:05:32
问题 I want to apply a detector algorithm to detect empty areas of parking and I have read about SIFT and SURF, but I can't quite understand it. I have seen examples of comparison between two images, but that's not what I want. Could you explain about how to use SURF or SIFT on the issue of detecting empty spots on parking? I have also read about color histogram, can I have some documentation about it? I am working with OpenCV python 2.4.9 and 2.7 回答1: It depends on what you exactly want to

object recognition performance not good

由 旧时模样 提交于 2019-12-06 15:59:40
I am trying to do object recognition using algorithms such as SURF, FERN, FREAK in opencv 2.4.2. I am using the programs from opencv samples without modifications - find_obj.cpp, find_obj_ferns.cpp, freak_demo.cpp I tried changing the parameters for the algorithms which didn't help. I have my training images, test images and the result of FREAK recognition here As you can see the result is pretty bad. No feature descriptors is detected for one of the training image - image here Feature descriptors are detected outside the object boundary for the other - image here I have a few questions: Why

OpenCV on iOS: False matching with SurfFeatureDetector and FlannBasedMatcher

由 痞子三分冷 提交于 2019-12-06 13:31:08
问题 I am trying to use OpenCV's feature detection tools in order to decide whether a small sample image exists in a larger scene image or not. I used the code from here as a reference (without the homography part). UIImage *sceneImage, *objectImage1; cv::Mat sceneImageMat, objectImageMat1; cv::vector<cv::KeyPoint> sceneKeypoints, objectKeypoints1; cv::Mat sceneDescriptors, objectDescriptors1; cv::SurfFeatureDetector *surfDetector; cv::FlannBasedMatcher flannMatcher; cv::vector<cv::DMatch> matches

Measure of accuracy in pattern recognition using SURF in OpenCV

由 左心房为你撑大大i 提交于 2019-12-06 11:37:55
问题 I’m currently working on pattern recognition using SURF in OpenCV. What do I have so far: I’ve written a program in C# where I can select a source-image and a template which I want to find. After that I transfer both pictures into a C++-dll where I’ve implemented a program using the OpenCV-SURFdetector, which returns all the keypoints and matches back to my C#-program where I try to draw a rectangle around my matches. Now my question: Is there a common measure of accuracy in pattern

OpenCV for Android - training SVM with SURF descriptors

由 我与影子孤独终老i 提交于 2019-12-06 06:07:30
问题 I need some help in training a SVM for an Android app. I have a set of images in different classes (12 classes) and got all descriptors from them. I managed to get the same amount of descriptors for each image. What I need is to train a SVM for my android application with those descriptors. I'm not sure if I should train it in the Android emulator or write a C++ program to train the SVM and then load it in my app (if I use the OpenCV's lib for windows to train the SVM and then save it, will

SIFT and SURF feature extraction Implementation using MATLAB

由 ╄→尐↘猪︶ㄣ 提交于 2019-12-06 04:18:59
问题 I am doing an ancient coins recognition system using matlab. What I have done so far is: convert to grayscale remove noise using Gaussian filter contrast enhancement edge detection using canny edge detector. Now I want to extract feature for classification. Features I thought to select are roundness, area, colour, SIFT and SURF. My problem is how I can apply SIFT and SURF algorithms to my project. I couldn't find built-in functions for both. 回答1: you can find a matlab implementation of SIFT

Open CV object detection : ORB_GPU detector and SURF_GPU descriptor extractor

由 二次信任 提交于 2019-12-06 04:17:05
I was just making a small experiment to play around with different detector/descriptor combinations. My code uses an ORB_GPU detector for detection of features and SURF_GPU descriptor for calculating the descriptors. I uses a BruteForceMatcher_GPU to match the descriptors and i am suing the knnMatch method to get the matches. The problem is I am getting a lot of unwanted matches, the code is literally matching every feature it could find in both the images. I am quite confused with this behavior. Following is my code ( GPU version ) #include "stdafx.h" #include <stdio.h> #include <iostream>
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