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Questions tagged [image-processing]

Anything related to digital image processing, i.e. the theory and the techniques used to extract or manipulate information from digital images.

Image Processing involves any kind of signal processing in which the input is an image. The output can also be an image, or it can be information relative to the input image. Most image processing techniques involve treating the image as a two-dimensional array and applying standard signal processing techniques to it. Though optical and analog image processing are both well defined in the space of image processing, the tag image-processing in SO solely refers to digital image processing.

A good start on the field is having a look at the next links:

For an in-depth collection of explanations of a number of image processing topics, have a look at CVonline.

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Image Processing: Algorithm Improvement for 'Coca-Cola Can' Recognition

One of the most interesting projects I've worked on in the past couple of years was a project about image processing. The goal was to develop a system to be able to recognize Coca-Cola 'cans' (note that I'm stressing the word 'cans', you'll see why…
Charles Menguy
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How do I find Waldo with Mathematica?

This was bugging me over the weekend: What is a good way to solve those Where's Waldo? ['Wally' outside of North America] puzzles, using Mathematica (image-processing and other functionality)? Here is what I have so far, a function which reduces…
Arnoud Buzing
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Peak detection in a 2D array

I'm helping a veterinary clinic measuring pressure under a dogs paw. I use Python for my data analysis and now I'm stuck trying to divide the paws into (anatomical) subregions. I made a 2D array of each paw, that consists of the maximal values for…
Ivo Flipse
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How to detect a Christmas Tree?

Which image processing techniques could be used to implement an application that detects the Christmas trees displayed in the following images? I'm searching for solutions that are going to work on all these images. Therefore, approaches that…
karlphillip
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Recommendation for compressing JPG files with ImageMagick

I want to compress a JPG image file with ImageMagick but can't get much difference in size. By default the output size is bigger than the input. I don't know why, but after adding some +profile options and setting down the quality I can get an…
Javis Perez
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Representing and solving a maze given an image

What is the best way to represent and solve a maze given an image? Given an JPEG image (as seen above), what's the best way to read it in, parse it into some data structure and solve the maze? My first instinct is to read the image in pixel by…
Whymarrh
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How do I crop an image using C#?

How do I crop an image using C#?
sandy101
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What is the best java image processing library/approach?

I am using both the JAI media apis and ImageMagick? ImageMagick has some scalability issues and the JNI based JMagick isn't attractive either. JAI has poor quality results when doing resizing operations compared to ImageMagick. Does anyone know of…
Daniel Honig
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How to merge a transparent png image with another image using PIL

I have a transparent png image foo.png and I've opened another image with: im = Image.open("foo2.png") Now what I need is to merge foo.png with foo2.png. (foo.png contains some text and I want to print that text on foo2.png)
Arackna
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Simple and fast method to compare images for similarity

I need a simple and fast way to compare two images for similarity. I.e. I want to get a high value if they contain exactly the same thing but may have some slightly different background and may be moved / resized by a few pixel. (More concrete, if…
Albert
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Is there a way to detect if an image is blurry?

I was wondering if there is a way to determine if an image is blurry or not by analyzing the image data.
Sam
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How can I quantify difference between two images?

Here's what I would like to do: I'm taking pictures with a webcam at regular intervals. Sort of like a time lapse thing. However, if nothing has really changed, that is, the picture pretty much looks the same, I don't want to store the latest…
carrier
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How to resize an image with OpenCV2.0 and Python2.6

I want to use OpenCV2.0 and Python2.6 to show resized images. I used and adopted this example but unfortunately, this code is for OpenCV2.1 and does not seem to be working on 2.0. Here my code: import os, glob import cv ulpath = "exampleshq/" for…
Bastian
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“Diff” an image using ImageMagick

How can I get the difference between two images? I have the original image. Someone has written on an exact duplicate of the original image. Now, I need to compare the original to the written on image and extract just the writing in image…
Justin Noel
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How can I improve my paw detection?

After my previous question on finding toes within each paw, I started loading up other measurements to see how it would hold up. Unfortunately, I quickly ran into a problem with one of the preceding steps: recognizing the paws. You see, my proof of…
Ivo Flipse
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