Cyclostationary Feature Detector: Performance doesn't vary with Change in SNR
signal-processing,detection,wireless,feature-detection,telecommunication
You need to take this one step at a time. I see errors in the signal generation as well as the statistic calculation. First, ensure that you are creating a cyclostationary signal! I ran the signal-generation code in the function above, and also looked at it. It looks like a...
OpenCV, How to delete small pixels and fill whole area of interrest
The simplest method is just to find only external contours (function findContours, use flag CV_RETR_EXTERNAL). To avoid detection of very small contours set some threshold value for contour area - drop all contours with area (contour area can be calculated using contourArea) smaller than this threshold. Alternative approach is to...
OpenCV/C++ - SIFT keypoint detection and corresponding descriptors
opencv,detection,sift,keypoint
SIFT stands for "Scale-invariant feature transform". It detects keypoints on multiple scales. The circles on your image probably refer to the scale on which the keypoint was detected. the keypoint positions in black areas don't seem completely unlikely to me: if you suppose that the area they look at is...
Detect mouse direction - JavaScript
javascript,mouseevent,mouse,detection
Stick with pageX and define oldx in a higher scope, otherwise it's always zero var direction = "", oldx = 0, mousemovemethod = function (e) { if (e.pageX < oldx) { direction = "left" } else if (e.pageX > oldx) { direction = "right" } oldx = e.pageX; } FIDDLE...
Fight detection with OpenCV
Pure optical flow or feature detection between frames would not help much because although they would track body movements, the computer cannot associate that with fighting. I would suggest looking into programs like Caffe, implemented by Berkeley, which uses neural networks to identify things based off learning from models.
Detect if drawing a path is a circle/rectangle in xcode
ios,xcode,detection,shapes,uibezierpath
You need to segment the data points first. Google on "stroke segmentation" to find related articles. One simple and fast algorithm is to compute the forward slope and backward slope for each data point, then compute the turning angle between forward slope and backward slope. If the turning angle is...
detect quite brighter spots on the image
c++,opencv,image-processing,detection
Generally, the technique is to blur the image so that small-scale details become irrelevant and only large-scale differences in the background illumination are retained. You then subtract the blurred image from the original to remove the uneven illumination, leaving only the localised features visible. My preferred tool is ImageMagick, but...
how to detect the iPhone is falling down or moving upwards in objc or swift?
Apple iPhone 6 has integrated barometer sensor so this might be the sensor that you are looking for. To access barometer data you will need to use CMAltimeter and CMAltitudeData classes
Switch Screen/Activity By Swiping Android Java
java,android,listview,swipe,detection
I think swipe should be from one fragment to another fragment not from activity to another avtivity.. http://android-developers.blogspot.in/2011/08/horizontal-view-swiping-with-viewpager.html http://developer.android.com/training/implementing-navigation/lateral.html...
Color detection on GIF or PNG image
php,image,image-processing,imagemagick,detection
I had another attempt at this, using some Connected Component Analysis software I wrote in C. It is readily compiled on any OS X/Linux/Windows machine. So, here is the script: #!/bin/bash # Make red areas white and all else black for blob analysis convert http://i.stack.imgur.com/qqein.png \ -fuzz 50% \ -fill...
How accurate is “intersect” method?
java,geometry,collision,detection
There's nothing wrong with the code you've provided. Nonetheless, I have found the answer to your question: I can't see where does the problem comes from.. I hope someone can spot what I couldn't.. The obstacle is drawn in a different position than is stored in the variable cercleInfluence. The...
Detect custom shape OpenCV
opencv,real-time,shape,detection
As the commenters have eluded, you can use template matching to detect custom shapes. So What Is Template Matching? Template matching is a technique in digital image processing for finding small parts of an image which match a template image. It can be used in manufacturing as a part of...
How to detect audio transients in iOS
There are a couple of simple basic ideas you can put to work here. First, take the input audio and divide into small sized buckets (on the order of 10's on milliseconds). For each bucket compute the power of the samples in it by summing the squares of each sample...
Finding square centers from a picture
python,opencv,image-processing,detection
You may need to use Image Moments. As the pre-processing steps, threshold the source to create mask of squares, and then pass to findcontours. ...
Java 3D LWJGL collision
java,lwjgl,models,collision,detection
You have a few options here. The easiest is to simply create an axis-aligned bounding box (AABB) around the object; this can be done algorithmically by simply finding the minimum and maximum values for each axis. For some applications this will work fine, but this obviously isn't very precise. It's...
simple 2d collision in monogame (using xna pipeline)
c#,collision,detection,monogame
SOLVED: turns out that it was no the collision that was the problem, but what occured inside the if-statements :)
Calculate the coordinates of a point in a line
m= (y2-y1)/(x2-x1) = (y4-y1)/(x4-x1)=1 as slope is 45 degree. so x4=x1+y4-y1; substitute y4=y3; then X4 = x1+y3-y1; ...
Can TXL be used for code clone detection
c++,frameworks,clone,detection
Yes, we can. Code clone detector such as : NiCad clone Detector has been developed on the TXL language. It involves three main stages: parsing, normalization, and comparison, which almost covers both the text-based and token-based approaches. You may click on this link to get the detailed documentation of the...
Wink detection on Google Glass with XE22
android,google-glass,detection,aero-glass
The library you posted is pretty outdated (last change 11 months ago). There is currently no official way to detect a wink. I had the same problem to detect only the wink and stop glass to take pictures when detecting it. There are several ways to detect such EyeGestures. Here...
OpenCV HSV weird converted
Looking at your result image I think that you are only using the H channel of the original image in your algorithm. The false positive detection can inherit from that the some part of the healty skin has quite the same H value than the hematoma has. You can see...
Detect keyboard on windows 7 using C#
c#,wpf,windows-7,keyboard,detection
Ok, so I found this solution a few days ago and it seems like it should work well as it will also not display the onscreen keyboard if a keyboard is attached to a touchscreen device (at least it shouldn't unless the OS overrides it, I have yet to test...
Check the document password protected or not
java,detection,password-protection,tika
No, there is no way to check in advance. This is because Tika won't know the file is password protected until it gets a fair way through processing it If you know the password for a file, you should use logic something like: ParseContext context = new ParseContext(); context.set(PasswordProvider.class, new...
Mail address validation JAVA
java,validation,boolean,character,detection
Here you have a regex for validating mail addresses: Java regex email...
Android: How to detect and collect multiple clicks (on multiple views) before batch processing
Ended up doing it via Handler which is quite simple for this case. For those who are interested, I defined a handler in the activity that handles a designated message which is to process something immediately. Then on every click, I clear the message queue and then send a message...
How to detect a bending person using Matlab
matlab,image-processing,computer-vision,detection,matlab-cvst
Just to clarify, are you working with a video? Is your camera stationary? In that case, you should be able to use vision.ForegroundDetector to detect anything that moves, and then use regionprops to select the blobs of the right size. If regionprops does not work for you, you may want...
HTML5 Canvas Collision Detection
html5,canvas,collision,detection
I can only append to what markE already says in his answer (we seem to be working on this simultaneously :) ). I will first point out a more serious bug in the code: You are using fill() without a beginPath() first. This will slow down the code loop rapidly....
Detect the position of a pattern of numbers in a matrix in R [closed]
According to your new rules, may be this helps: data1 <- data #changing some elements to test the code data1[2,8] <-2 data1[4,1] <- 1 ##The code is for the row indx <- which(t(sapply(split(data1 == pattern, row(data1)), { function(x) colSums(sapply(1:(length(x) - 3), function(i) x[seq(i, i + 3)]), na.rm = TRUE) ==...
a trivial Presence detector with raspberry using python
python,raspberry-pi,detection,led
You're so close! Let's jump to what's correct first. In your second while True block, your code already sleeps (waits) for an interval before continuing. Here it is with some comments and formatting corrections: while True: # this reads from your GPIO to set a variable Current_State = GPIO.input(GPIO_PIR) #...
AForge net simple shape detection error
Your problem is that AForge have there own Point struct so your ToPointArray method actually returns an Aforge Points array rather than an array of the needed .net Point. The simplest solution is to fully qualify the type you want to use, so your method would become private System.Drawing.Point[] ToPointsArray(List<IntPoint>...
Cannot use Boost GIL to detect image filetype (exception not caught)
c++,boost,detection,image-formats,boost-gil
I don't understand why the exception as thrown apparently cannot be caught. It might be a bug. However, to accomplish the task I'd suggest libmagic or identify (from ImageMagick) which does what the other answer suggests. This answer contains an example of how to use libmagic (which is usually present...
Handle a value being changed in a c++ struct
c++,struct,operator-overloading,detection
I will assume your struct is named Fun Solution 1: Add getter, setter and notify I would write a getter and a setter for each properties of the said struct. It would look like this: struct Fun { Fun(System& sys): system{sys} {} void setGun(int g) { gun = g; notify();...
Vehicle Detection and Tracking unisng Lucas kanade
image-processing,tracking,detection,car
I detected contours and filtered them by size. That worked for me using the same video available on the link posted by GiLevi (http://www.behance.net/gallery/Vehicle-Detection-Tracking-and-Counting/4057777). You could also perform background sutraction, and detect blobs, on the foreground mask; again filtering by size, so as to differentiate from cars, people etc.
detection and counting objects in images using matlab [closed]
matlab,object,image-processing,detection,counting
There is a lot of research in this area, but not specific to Matlab. Try using google scholar to search for papers with "computer vision counting" or similar keywords. Richard Szeliski also has a very good, free to download textbook on Computer Vision which could be helpful: http://szeliski.org/Book/. Topics like...
Detect invalid certificate for WebSocket
javascript,websocket,detection,certificate-authority
No, it is not possible. The client will close with 1006 code: 1006 1006 is a reserved value and MUST NOT be set as a status code in a Close control frame by an endpoint. It is designated for use in applications expecting a status code to indicate that the...
Boundary Detection
javascript,canvas,collision,detection,boundary
You could save the last "valid" (in white area) x/y for the green dot. If the dot later moves to an invalid area, you could position the dot back to the last valid position. Example code and a Demo: http://jsfiddle.net/m1erickson/pq7QZ/ <!doctype html> <html> <head> <link rel="stylesheet" type="text/css" media="all" href="css/reset.css" />...
Extract Point Cloud from a pcl::people::PersonCluster
c++,detection,printer-control-language
For those that are interested I resolved my problem. In the forum of pcl I found a post where the same developer of the people detector I used gave the answer. So basically: // Get cloud after voxeling and ground plane removal: PointCloudT::Ptr no_ground_cloud (new PointCloudT); no_ground_cloud = people_detector.getNoGroundCloud(); //...
Flash actionscript 3, collision detection upon keypress
actionscript-3,flash,collision,detection
You can only detect collision upon clicking because you have put your hitTestObject inside a function that is a MouseEvent function. What you could do is that instead of testing collision on MOUSE_UP and MOUSE_DOWN, test the collision with a frequent interval of time by either using TimerEvent or directly...
Java, is there a better way to do key detection?
The simplest solution, and generally the more powerful, would be to use the key bindings API The main problem with KeyListener is that is focus contextual. That is, the component it is registered to must be focusable AND have focus before it will raise key events...
Opencv c++ detect and crop white region on image
If your image has no non-black outlier (like noise) you can ignore the canny and the findContours and instead just create the bounding rect from all non-black pixel locations: int main() { cv::Mat in = cv::imread("CropWhite.jpg"); // vector with all non-black point positions std::vector<cv::Point> nonBlackList; nonBlackList.reserve(in.rows*in.cols); // add all non-black...