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Computer Vision

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List of Articles. Computer Vision. These days, you can see QR codes almost everywhere. You see them at stores, on products, on screens. So one day, I was curious how the gears are put together to read QR codes. I ended up reading the ISO/IEC 18004 standard. Read more Here’s an interesting article – we’ll implement canny edges. A lot of people consider the Canny Edge Detector the ultimate edge detector. An Image moment is a number calculated using a certain formula. In computer vision, thresholding is probably the most basic operation. Detecting edges is one of the fundamental operations you can do in image processing. K-Nearest Neighbors is a very simple machine learning algorithm.

Here’s an interesting project that I’ll be taking your over the next few days. Convolutions are a very important tool for anyone interested in signal processing. Labeling connected components in an image is a common operation. JavaScript code to calculate the Pearson Correlation Coefficient « steve gardner. Correlation. Correlation The term correlation simply refers to the degree to which two or more sets of data show a tendency to vary together. The strength of the positive (increase, increase) correlation coefficient can vary from .00 to 1.00. Determining the Correlation Coefficient (example in the form of test-retest reliability) Step 1: List scores. Participant # 1st Scores 2nd Scores n 1 = 10 n 2= 10 Step 2: Find the z score for each test score using the formula: About Z Scores Z scores are a type of standard score.

Participant # lst Test Z Score 2nd Test Z Score Step 3: Sum the scores from each test. R = Σ ZxZy / N Participant # ZxZy 1. 0 2. .82 3. 1.22 4. .71 5. 0 6. 0 7. 4.60 8. .10 9. -.16 10. .10åZxZy = 7.39 (åZxZy) / 10 = 0.74* *This answer is the correlation coefficient About Pearson r The Pearson r is the most commonly used measure of correlation, sometimes called the Pearson Product Moment correlation.

Return. ‎www.bc.edu/content/dam/files/schools/cas_sites/cs/local/bach/2001/02KristenGrauman.pdf. AS3 Webcam Motion Tracking › Detecting and Tracking an Objects Movement in Flash. Update Ok, you can now grab the MotionTracker source code (AS2 & AS3). Version 2 eventually will include the other methods for detecting and tracking motion which I mentioned. For now I have just included code for the technique used in the demo. Download: AS3 Webcam Motion Tracking For those of you without access to a webcam (and as an example of a practical use for this class) here is a short video demonstrating the program I wrote for the installation piece.

End of update Webcam required to view the demo (obviously…) I’m currently working on putting up a show, part of which will be a live generative piece, constructed from the movement of visitors in the gallery space. Anyway; I researched the concept of motion tracking, and made some notes on my own ideas. One of the most attractive ideas was to divide the screen into a grid, and average the colours within each segment at regular intervals. Here’s how it works So that takes care of the motion detection, but what about the tracking?