OpenCV (Open Source Computer Vision) is a cross-platform library of programming functions for real time computer vision.

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Is opencv work fast with android like in desktop?

I am working on android applications and I am now using openCv for it , but when I apply the build in filter algorithms for my app it works slow and show result ...
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Where can I find annotated databases of faces with profile views?

I'm working on a project that uses AAMs (Active Appearance Models). I'd like to have an AAM with profile view. Is is possible to get free annotated images of faces in a profile view?
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41 views

Histogram and binary image in opencv? [closed]

I would like to compute how many zeros and ones (e.i. 255) in a binary image. The following code to generate a binary image by using Matlab. ...
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27 views

reducing chroma of image on client and reconstructing on server

I have a C# desktop application. I am using Emgu wrapper to openCV. My objective is to upload images in the most efficient way I can. I have hit upon the idea of loading an image (jpeg) into memory ...
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40 views

Sharpening an image using emgu

I have c# desktop application and I am using emgu framework as a wrapper for OpenCV. I am trying to sharpen an image because the input images are not great. I tired a technique I found via searches ...
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1answer
71 views

How to make filters?

I am trying to make filters like sepia filter in my app like other photo editing applications , till now I don't have any idea about it , Can any one help me out ...
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2answers
95 views

Improve contrast when image has a flood of white balancing

I have an image taken a night time. I apply _EqualizeHist to it. But the result is a high level of whiteness running through the image. This is the image: I had asked this question in a slightly ...
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81 views

Motion and Distortion Estimation using multiple still images?

TL/DR: I'd like to take the median of lots of images to make a single "better" image. The problem is, the camera is slowly moving, and there is significant lens distortion. On the plus side the ...
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1answer
107 views

Corner detection using Chris Harris & Mike Stephens [duplicate]

I am not able to understand the formula, What is $W$ (window) and intensity in the formula mean, I found this formula in opencv doc ...
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120 views

Refining lines in an image with openCV

So in my project I am extracting the lines of an image with openCV2 by firstly creating a skeleton: I convert it tp a binary image, invert it (to make it work with morphological operations) and then ...
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1answer
55 views

Mat class of c++ in open cv [closed]

I am a beginner in opencv and have started learning it using visual studio 2012 and opencv 2.4.7 . But i got stuck at very beginning .I want to know about Mat used in Opencv .It is a class and an ...
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43 views

Subsetting a GeoTIFF Image

I wish to create a subset of a multiband image in OpenCV / Python. The image is in the GeoTiff format. The bands might be 16 bit or 8bit. How do I achieve this using OpenCV and Python.
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516 views

Need help in panoramic image stitching using emgu cv

I am doing a project on panoramic stitching of Images using Emgu CV (Open CV for C#). Till now I have done some work that stitches images but the output is kinda weird. This is what I am getting: My ...
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126 views

Calculating an HSV histogram

I have to compute an HSV histogram of a colored image. Is it same as an H-S histogram? I have found H-S histogram computation code everywhere. What is the method to change an H-S histogram to an ...
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1answer
56 views

How to use clustering file after training

I trained the data using BOG with SVM , i trained it , now i just want to open it through xml , i don't want to train it again and again on every run , I trained ...
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2answers
589 views

Licence plate detection with different backgrounds

I just studied the Algorithm of ANPR (Automatic Number Plate Recognition) from the chp 5 of book Packtpub.Mastering.OpenCV.with.Practical.Computer.Vision.Projects in which they detect the vehicle ...
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1answer
103 views

remove spatial sinusoid noise from 2d image

Given a 2D image where each row of pixels is shifted by some amount horizontally in a sinusoid fashion, is it possible to recover the original image? Imagine a camera that can capture one row at a ...
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1answer
111 views

How to select the specific frame with object

I am detecting the object from the live camera through feature detection with svm , and it read every frame from camera while predicting which affect its speed , i just want that it should select the ...
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368 views

OpenCV: Problem at creating a Skeleton of Lines

I need to get the lines from a photographie of a sheet of paper. While recherching, I came along this, where one answer referred to this blog entry. Now I am having trouble with this approach. I have ...
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1answer
851 views

Influence of image size to edge detection in OpenCV

I need to scan an image in OpenCV and obtain the lines. For this I use the canny edge detector and then the propabilistic Hough transform, with which I actually get the lines. The problem now is that ...
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2answers
689 views

Why do we use keypoint descriptors?

I just studied about SURF and I'm going for its implementation, but I still didn't understand why we use descriptors. I understand what keypoints are and their purpose, but when we extract the ...
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445 views

How to recognize hexagonal tiling in boardgame?

I would like to recognize the boundaries of a hexagonal tiling in a photograph, like in image below: It seems to me, that a standard approach at a square grid is to first detect corners (e.g. ...
6
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1answer
204 views

Jigsaw puzzle: isolating the pieces (separating “stuck” blobs)

I'm new to image processing, and I'm trying to get my feet wet. I have taken a picture of some jigsaw puzzle pieces and I want to isolate the pieces. I am using the Python SimpleCV library to do ...
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79 views

Garment Cropping from mannequin

I have two images – mannequin with and without garment. Please refer sample images below. Ignore the jewels, footwear on the mannequin, imagine the second mannequin has only dress. I want to ...
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134 views

calcGlobalOrientation: problem with thin objects (e.g. a rod)

I would like to pose a problem regarding the function calcGlobalOrientation when used with the Motion Template technique. First of all, consider that I also post the same question at the following ...
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2answers
1k views

How to compute Image Gradients?

How to compute Image gradients? In X Direction - Kernel : -1 0 1 In Y Direction - Kernel : -1 0 1 Let's assume my input image is: unsigned char* imgImage; ...
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64 views

How can I create polygon estimates of each body part/limb that is present in an image which always contains one person?

Background I am working to identify and isolate each human limb of a known person, in pose, in an image which is relatively noisy. It should also be noted that the image is a snapshot extracted from ...
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146 views

How to get more accurate results with OpenCV

I would like to ask about this function in OpenCV: cvTermCriteria( CV_TERMCRIT_ITER | CV_TERMCRIT_EPS, 20, .3 ) How do I get more accurate results - do I need ...
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1answer
336 views

Tracking object that is missing in some frames

I am trying to track small object in videos using LK but the problem is, some time the object does not appear in the frames ! How can I track an object that does not appear in few frames ?? how ...
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1answer
210 views

Image processing functions for quality control

I have to use image processing for quality control of a cookie manufacturer (as a part of my project). The program must be able to detect oversized, undersized, distorted cookies, cookies having ...
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261 views

Detecting a filled glass object

I've been sent here from this question in stackoverflow, please excuse me if the question comes too specific and it's not in the manners in here:) The task is to find a glass with specific liquid in ...
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1answer
211 views

False SURF output in video

I am trying to find the three cervical vertebrae (C2 , C3 , C4)in x-ray videos (gray images) I am using SURF to identify the place that has these 3 vertebrae (big box for all of them ) SURF gives me ...
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1answer
301 views

Image processing: using PCA for 3d object recognition

I read this lecture on using PCA/eigenfaces: http://www.cse.psu.edu/~rcollins/CSE486/lecture32.pdf And I want to use this general procedure to recognize a 3D clay model that I took pictures of from ...
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Help in Retraining a HOG Descriptor using SVMLight

I am currently trying to count cars using OpenCV 2.4.4 with a HOG descriptor. Because a model for car detection is not available in OpenCV, I am creating my own model using SVMLight and a dataset of ...
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3answers
222 views

Image processing, recognizing a small feature in a larger image

I am trying to write an image processing program to recognize bubbles in oil. It has been suggested I try computing the convolution of the image and an image of a typical bubble. i.e. : ...
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608 views

Detect lanes from a filtered image

I am working on lane detection system and I would like some suggestions from you as to how to detect lanes from a filtered image which I got after performing certain operations. Firstly, I should ...
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1answer
168 views

How can i compute perimeter and area of a skeletonized circle?

In opencv if i use findcontours function, i get contours and i can compute area, perimeter, convex hull. if i use a Skeletonized image of a circle how can i compute perimeter,area, convex hull of the ...
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1answer
315 views

How to relocate face points in opencv / face distortion?

I have to simulate facial expressions on a face image ( say open mouth ). For this I first extracted the facial feature points and found the corners of the lips. Now I need to deform the image by ...
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1answer
459 views

Texture mapping on a 3D face from 2D face image

I have 3D points (xyz) of a face image and I have 2D face image of the same person. The 3D points of the face are such that If I project the points to 2D plane, it matches with the 2D face image. I ...
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2answers
280 views

Object-Recognition using SIFT: Switching the order of images creates two different results

I've developed a large test-system which can use every interest-point-detector and -descriptor. I use it for evaluation of the given algorithms with the standford-image-collection of cd-covers. This ...
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1answer
184 views

How to calculate Noise and distortion of an image?

I need to make an application in iphone which needs to calculate noise, geometric deformation other distortions in an image. How to do this? I have done some image processing stuff with opencv + ...
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245 views

Why do object-boundaries look better on a badly rectified image?(openCV stereo correspondence)

I got 2 pictures which is almost parallel, and not positioned very far from each other. I'm using OpenCV to try to create a disparity map (Stereo correspondence). Because I'm trying to use it in a ...
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120 views

Separating similiar object in an image

I have posted a question on Stackoverflow and was suggested to post here. Please refer this question for the images: Similar Question: I have used SURF Keypoints and a FLANN Based matcher and ...
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53 views

There are other shape properties scale-rotation invariant except HuMoment?

There are other shape properties scale-rotation invariant except HuMoment? There are example that show me how can i implement them? I find this example in c++ ...
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3answers
139 views

Determining Toy Helicopter Orientation From Image

I am working on developing an autonomous control system for toy IR remote-controlled helicopters (like the Syma s107, for example) using a webcam and an Arduino with some IR LEDs. I am using C++ with ...
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250 views

Using GavabDB for 3D face reconstruction from frontal image

Project: 3D face reconstruction Input: 2D frontal face Image Output: 3D face Reconstruction and expression simulation Platform: Matlab or Opencv cpp. I found out after study that 3D Morphable Models ...
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264 views

How to recognize a zebra crossing from top view using OpenCV?

How to recognize a zebra crossing from top view using OpenCV? It is not a straight zebra crossing - it has some twists and turns. I have some ideas: parallel line detection, but the available ...
2
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1answer
123 views

Safe Point Thinning Algorithm - How to?

I am relatively new to image processing and am working on a project that requires the thinning of binary images. In the literature, I've seen references to the Safe Point Thinning Algorithm(SPTA) ...
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147 views

Qualitative Evaluation of Interest-Point-Detectors and Descriptors in Computer Vision

I'm writing on a qualitative evaluation study of interest-point-detectors and descriptors. I've read all Mikolajczyk papers as well as most of the surves from Datta et al. etc. Now I'm implementing an ...
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148 views

STASM or AAM which is more efficient

I am working in face detection and recognition project. I am using STASM for face detction and locating face landmarks. On googling I found AAM (Active Appearance Model) and found that it is also used ...