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Questions tagged [image-comparison]

Methods, algorithms and techniques for the programmatic comparison of image data.

Methods, algorithms and techniques by which images can be programmatically compared, either to one another or to a database of extracted image features.

Meaningful image comparison will typically involve the extraction of some of features from the images in question, as metadata. Many techniques for feature extraction (and subsequent feature selection) come from the content-based image retrieval field.

Typical image-comparison schemes necessitate some manner of image processing as well.

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Image comparison to identity and map identical pixels

I'm building this for iOS using Swift — either via CoreImage or GPUImage, but if I can build it in Python or Node/JavaScript, that'd work too. Feel free to answer abstractly, or in a different language entirely — I'll accept any answer that roughly…
brandonscript
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A good method for detecting the presence of a particular feature in an image

I have made a videochat, but as usual, a lot of men like to ehm, abuse the service (I leave it up to you to figure the nature of such abuse), which is not something I endorse in any way, nor do most of my users. No, I have not stolen…
Armen Michaeli
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Matching template imge(scaled) to Main/larger image

I want to find/check subImage/template image in main image and want to know its coordinates, I have used code given at following link to implement it, Check presence of subimage in image in iOS It is working fine, if the size of the template image…
Mehul Thakkar
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Algorithm optimization - parallel AsyncTasks or threads?

I currently have a single AsyncTask which currently compares images using the bubble sort technique using OpenCV. Say, I have to compare 400 images to each other. This would mean 400*401/2=80,200 comparisons. Let's assume one comparison takes 1…
Karthik Balakrishnan
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Compare a shape in an image with PHP

I'm trying to compare shapes in php. I have a database with a lot of images, in those images there is a shape ( mostly in the center of the image ). Now I want to compare those images to a Shape. The input is a shape (png) that is exact the same…
S.Visser
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Using OpenCV to recognise similar (not completely identical) simple images?

Say I have a very simple image or shape such as this stick man drawing: I also have a library of other simple images which I want to compare the first image to and determine the closest match: Notice that the two stick men are not completely…
user1636130
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Similar image search using an image

I am working on a project in which the two images will be checked for similarity like 'Google Image Search by image'. I searched through Google and also on various sites including stackoverflow and learnt about various techniques like histogram,…
user3780435
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Detecting a Specific Watermark in a Photo with Python (without SciPy)

I have a large number of images (hundreds of thousands) and, for each one, I need to say whether or not it has a watermark in the top right corner. The watermark is always the same and is in the same position. It takes the form of a ribbon with a…
alan
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Comparing image in url to image in filesystem in python

Is there a quick and easy way to do such comparison? I've found few image compare questions from stackoverflow but none of those actually proved answer for this question. I have images files in my filesystem and a script that fetches images from…
Oskari Kantoniemi
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Getting stuck on Matlab's subplot mechanism for matching images' points for vlfeat

I am doing vlfeat in Matlab and I am following this question here. These below are my simple testing images: Left Image: Right Image: I did a simple test with 2 simple images here (the right image is just rotated version of the left), and I…
Karl
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Irregular Shape Comparison between two inputs

I'm trying to come up with a scoring system for some behavioural psychology research. I ask people to draw a letter, then trace over it, both on a graphics tablet. I want to assess the accuracy of this trace. So, you draw any letter ('a'), then you…
dgmp88
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Find differences between two images but *not* pixel to pixel

I hope someone will be able to help me. I have pairs of black and white images that resulted from scanning texts with a large scanner (resulting files are up 500M). The texts scanned are nearly identical, and I need to check if there are any…
user819490
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Determining Similarity of Edge-Detection-Processed Images

I was hoping that I could achieve some guidance from the stackoverflow community regarding a dilemma I have run into for my senior project. First off, I want to state that I am a novice programmer, and I'm sure some of you will quickly tell me this…
Mike D.
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Detecting somewhat different Images - Is there any java implementation for perceptual hash and differential hash?

I am working on a solution for detecting similar and somewhat different media Images. I have come across many articles suggesting techniques for handling Images for instance - Image comparison - fast algorithm file-hash based (md5,sha1,etc) -…
Sumeet
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Image Comparison by Finger Printing

I'm looking for ways to find image duplicates by fingerprinting. I understand that this is done by applying hash functions on images, and each image would have a unique hash value. I am fairly new to image processing and don't know much about…
Humza
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