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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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How to fill OpenCV image with one solid color?

How to fill OpenCV image with one solid color?
Rella
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Viola-Jones' face detection claims 180k features

I've been implementing an adaptation of Viola-Jones' face detection algorithm. The technique relies upon placing a subframe of 24x24 pixels within an image, and subsequently placing rectangular features inside it in every position with every size…
Paul Lammertsma
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Convert opencv image format to PIL image format?

I want to convert an image loaded TestPicture = cv2.imread("flowers.jpg") I would like to run a PIL filter like on the example with the variable TestPicture but I'm unable to convert it back and forth between these types. Is there a way to do…
Arsenal Fanatic
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OpenCV Python: cv2.findContours - ValueError: too many values to unpack

I'm writing an opencv program and I found a script on another stackoverflow question: Computer Vision: Masking a human hand When I run the scripted answer, I get the following error: Traceback (most recent call last): File "skinimagecontour.py",…
ahmadux
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how to make the blur effect with react-native?

how to make the blur effect with react-native ? like 'background-image' and i want to switch the effect 'blur' and 'none'，'none' means no blur effect
12343954
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How would I tint an image programmatically on iOS?

I would like to tint an image with a color reference. The results should look like the Multiply blending mode in Photoshop, where whites would be replaced with tint: I will be changing the color value continuously. Follow up: I would put the code…
willc2
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How do I find Wally with Python?

Shamelessly jumping on the bandwagon :-) Inspired by How do I find Waldo with Mathematica and the followup How to find Waldo with R, as a new python user I'd love to see how this could be done. It seems that python would be better suited to this…
tdc
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Remove White Background from an Image and Make It Transparent

We're trying to do the following in Mathematica - RMagick remove white background from image and make it transparent. But with actual photos it ends up looking lousy (like having a halo around the image). Here's what we've tried so…
dreeves
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Use FFmpeg to resize image

Is it possible to resize an image using FFmpeg? I have this so far: ffmpeg. -i 1.jpg -vf scale=360:240 > 2.jpg I get the error message: At least one output file must be specified Is it possible?
Andrew Simpson
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Image Processing: What are occlusions?

I'm developing an image processing project and I come across the word occlusion in many scientific papers, what do occlusions mean in the context of image processing? The dictionary is only giving a general definition. Can anyone describe them using…
HaggarTheHorrible
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Image Processing, In Python?

I've recently come across a problem which requires at least a basic degree of image processing, can I do this in Python, and if so, with what?
akdom
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Combine 3 separate numpy arrays to an RGB image in Python

So I have a set of data which I am able to convert to form separate numpy arrays of R, G, B bands. Now I need to combine them to form an RGB image. I tried 'Image' to do the job but it requires 'mode' to be attributed. I tried to do a trick. I…
Ishan Tomar
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Converting an OpenCV Image to Black and White

How do you convert a grayscale OpenCV image to black and white? I see a similar question has already been asked, but I'm using OpenCV 2.3, and the proposed solution no longer seems to work. I'm trying to convert a greyscale image to black and white,…
Cerin
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Return a PHP page as an image

I am trying to read a image file (.jpeg to be exact), and 'echo' it back to the page output, but have is display an image... my index.php has an image link like this: and my php script does basically this: 1)…
Kladskull
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Detect and visualize differences between two images with OpenCV Python

I have two images and would like to make it obvious where the differences are. I want to add color to the two images such that a user can clearly spot all the differences within a second or two. For example, here are two images with a few…
PlsWork
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