detect object in image,how they did it. I think it is unbelieveable
this picture is download from a website,the team show their research result like this. I want to know how they did it, some body know tell me I will be appreciate. thank you ...
computer-vision
image focus calculation
Hi folks, I'm trying to develop an image focusing algorithm for some test automation work. I've chosen to use AForge.net, since it seems like a nice mature .net friendly system. Unfortunately, I can't seem to find information on building autofocus algorithms from scratch, so I've given it my best try: take image. apply sobel edge det...
How can I determine distance from an object in a video?
I have a video file recorded from the front of a moving vehicle. I am going to use OpenCV for object detection and recognition but I'm stuck on one aspect. How can I determine the distance from a recognized object. I can know my current speed and real-world GPS position but that is all. I can't make any assumptions about the object I'm...
What algorithm to use to obtain Objects from an Image.
Hi, I would like to know what algorithm is used to obtain an image and get the objects present in the image and process (give information about) it. And also, how is this done? Please do help me out! :) Thanks in advance. - Karthik.K ...
Connected Component Labeling in C++
I need to use the connected component labeling algorithm on an image in a C++ application. I can implement that myself, but I was trying to use Boost's union-find/disjoint sets implementation since it was mentioned in the union-find wiki article. I can't figure out how to create the disjoint_sets object so that it'll work with the image...
What preprocessing image techniques should I take in consideration before applying OpenCV's Viola-Jones method for face recognition ?
Hello, I am working for a project at school regarding face recognition, based on a technique described by Viola and Jones 2001/2004. I've read that the OpenCV has an implementation of this algorithm, and it works very good. I was wondering if you have any advices regarding what techniques (pre-processing) to apply to the images befor...
How can I detect and track people using OpenCV?
I have a camera that will be stationary, pointed at an indoors area. People will walk past the camera, within about 5 meters of it. Using OpenCV, I want to detect individuals walking past - my ideal return is an array of detected individuals, with bounding rectangles. I've looked at several of the built-in samples: None of the Python ...
3D Correspondences from fundamental matrix
In MATLAB I have calculated the Fundamental matrix (of two images) using the normalized Eight point algorithm. From that I need to triangulate the corresponding image points in 3D space. From what I understand, to do this I would need the rotation and translation of the image's cameras. The easiest way of course would be calibrate the ca...
Detecting center point of cross using Matlab
Hello, I have an image as shown above. Is it possible for me to detect the center point of the cross and output the result using Matlab? Thanks. ...
Line scanning openCV
below is a very simple code segment, but I am not able to understand why it is cribbing, can you please tell me what the error means: CvSize iSize; iSize= cvGetSize(I1); CvLineIterator *iter ; CvPoint p1,p2; long *arrH = new long[iSize.height + 1]; long *arrV = new long [iSize.width + 1]; for( int i=0; i<=iSize.height;i++) { ...
Classifying type samples from image files
Which approach would you suggest for automatically classifying type found in images? The samples are likely large, with black text on a white background. The categories are defined here, with some examples on each (Google Books link): http://bit.ly/9Mnu7P This is an extended version of the VOX-ATypI classification system. My initial t...
Triangulation & Direct linear transform
Following Hartley/Zisserman's Multiview Geometery, Algorithm 12: The optimal triangulation method (p318), I got the corresponding image points xhat1 and xhat2 (step 10). In step 11, one needs to compute the 3D point Xhat. One such method is Direct Linear Transform (DLT), mentioned in 12.2 (p312) and 4.1 (p88). The homogenous method (DL...
how do i calculate the centroid of the brightest spot in a line of pixels?
i'd like to be able to calculate the 'mean brightest point' in a line of pixels. It's for a primitive 3D scanner. for testing i simply stepped through the pixels and if the current pixel is brighter than the one before, the brightest point of that line will be set to the current pixel. This of course gives very jittery results throughou...
Adaptive threshold Binarization's bad effects
I implemented some adaptive binarization methods, they use a small window and at each pixel the threshold value is calculated. There are problems with these methods: If we select the window size too small we will get this effect (I think the reason is because of window size is small) At the left upper corner there is an original image,...
Image orientation maps
Hello, What is the most common way to get 4 Orientaton maps at 0, 45, 90 and 135 angles from Image. I want to apply orientation kernels. Is that good solution ? for 0 orientation -1 -1 -1 2 2 2 -1 -1 -1 for 45 orientation -1 -1 2 -1 2 -1 2 -1 -1 for 90 orientation -1 2 -1 -1 2 -1 -1 2 -1 for 135 orientation 2 -1 -1 -1 2 -1 -1 -...
How to access image Data from a RGB image (3channel image) in opencv
I am trying to take the imageData of image in this where w= width of image and h = height of image for (int i = x; i < x+h; i++) //height of frame pixels { for (int j = y; j < y+w; j++)//width of frame pixels { int pos = i * w * Channels + j; //channels is 3 as rgb // if any data exists if (data->imageD...
Generating labeled images for each glyph in a bitmap font file
Is there an easy way to generate a labeled bitmap image for each glyph contained in a given bitmap font file? I'm trying to convert a collection of Japanese .bdf fonts into a format usable in MATLAB and C++, where each glyph is used as the OCR classification key for the character it represents. ...
cvUndistort2 () and cvRemap () crash
Hi! I was doing example 11-1 of "Learning OpenCV" by Bradski. Unfortunately the given example doesn't work on my computer. The program is supposed to calibrate camera using chessboard and then output undistorted video output from the camera. The calibration part works fine, the problem arises when the program tries to undistort the i...
How do I extract surface normals (facade) at each pixel from google maps street view api?
In this google lat-long blog post ( http://google-latlong.blogspot.com/2009/06/introducing-smart-navigation-in-street.html ) they describe how they estimate the surface normal or facade orientation using 3D point clouds. Is there a way to extract/retrieve the surface normal at each pixel using the google street view api? ...
Displaying a digital "Down Marker" on a live video feed.
I was watching the Superbowl and I was wondering how the digital "Down Marker" was being displayed on the live video feed. Below is a screen show of the digital down marker which is a red line. Some behavior that I noticed is that the line is always displayed on the "field", so if a player is standing on the line, you can see his f...