Questions tagged [computer-vision]

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2
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0answers
53 views

Shape-from-shading algorithms?

Before I go to the effort of writing my own code, I was wondering if there is code available for shape-from-shading algorithms. These take an image (such as a black-and-white image, such as this) and ...
2
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0answers
28 views

Faster alternative to ImageCorrespondingPoints?

I'm trying to use ImageCorrespondingPoints to register frames in a video sequence. Computational speed is an important consideration for the application I am ...
3
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0answers
99 views

Find nearest crop of image within another image

ImageAlign[ref, i] works well when image i is fully contained within the reference image ref,...
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0answers
21 views

ImageContents not working on Wolfram Cloud iOS app

I tried using the experimental ImageContents[] function, introduced in MMA 12, on my PC (using Mathematica) as well as on my iPad (using Wolfram Cloud app). On my ...
0
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1answer
152 views

Best laptop specs for a better and faster numerical simulations [closed]

Hope all is well! I am planning to buy a laptop (Windows) and looking for your help to decide the specs that we need to speed up the numerical simulations using Mathematica. The Mathemtica code I used ...
7
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1answer
138 views

How to detect rectangles with certain colors in an image?

I'd like to find the red bordered rectangles in this image: Here are my example images: ...
4
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2answers
205 views

Extract partitions of images after edge detection

Given a edge detected image like this: I would like to extract each character into a sub-image, i.e so that each new picture only have one character. Is there a simple way of doing this in ...
6
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1answer
191 views

How to track a deformable rod in video?

I have a video of nanotubes in solution taken with a confocal laser microscope. I typically track these nanotubes with Fiesta or Fiji, but in this case, there is variation in brightness that is ...
0
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0answers
122 views

Use FacialFeatures in Python Web API?

Under the hood, FacialFeatures uses the net-model ResNet-101 Trained on Augmented Casia WebFace Data. I would like to see a tutorial-style answer on how one would ...
5
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0answers
123 views

How to extend ImageCases?

I was very excited to see ImageCases being documented in version 12. But I immediately desired a mechanism for adding more entities to ...
0
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1answer
125 views

Robust face detection

FindFaces doesn't work when people are far away from the camera. I'm looking for a single accurate method of detecting one or more people in an images, at all ...
10
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2answers
229 views

Efficient multicolor search

I'm hoping someone can help me improve the following fun code-snippet, which takes a target color and searches through a set of images to find the ones that most closely match: ...
16
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2answers
455 views

How to TextRecognize a screenshot of code?

Are there any specific tricks or options to help TextRecognize work on a screenshot of an Input Cell or code in general? For example, here's a screenshot that ...
4
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1answer
197 views

Extract names from a document [closed]

If I have a document, any document, it can be a book, an article, etc, how could I extract people's names from there? For example, if the input is an article, the output of the function would be the ...
3
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0answers
173 views

Fourier image correlation is likely to be wrong [closed]

I have images of two identical ellipses, which differ by the orientation. I want to obtain the difference angle between them by means of phase corelation method (https://en.wikipedia.org/wiki/...
1
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0answers
102 views

Performance of ImageCorrelate with a masked kernel (via custom distance function)

Context For an image in-painting task (filling in missing regions in an image, see image below; missing region printed red) I'd like to try a template matching approach. The idea is to use parts of ...
3
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0answers
473 views

Accessing advanced ZXing settings for BarcodeRecognize

Usual algorithms for detecting the presence of a QR-code in an image seem to have trouble detecting a code when it is tilted (especially at 45°). This is dependent on the resolution as well. The ...
1
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2answers
179 views

How to do the “Sketch colorization” like Project Scribbler using Mathematica? [closed]

Recently, the Adobe release the Project Scribbler Adobe Max 2017. The picture is from the P. Sangkloy, J. Lu, C. Fang, F. Yu and J. Hays. Scribbler: Controlling Deep Image Synthesis with Sketch and ...
0
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1answer
109 views

Removal Background with Shadows on HUE

I have an image of a leaf on a poorly white screen and need to find out just the leaf: The problem is that it contains greenish shadows, so simple color-based methods are not enough. Thus, I need ...
4
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1answer
142 views

Speeding up ImageCorrespondingPoints

I have the following problem: I am taking free-handedly photographs from the same scene during e.g. hiking, because sometimes I don't want to lug around a tripod. The goal is e.g. to create later on ...
1
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0answers
218 views

Rectangular object boundary detection

I would like to find the boundaries of an object: I have looked that the YOLO algorithm but it looks like the results cut off parts of the object a lot. What kind of algorithm can I use to achieve ...
1
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0answers
415 views

Apply a four-point transform crop to an image

I am attempting to straighten and crop an image by using Edge Detection. The original image looks like this. By using edge detection and finding the max and min values for the points regarding the ...
9
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1answer
212 views

Adding computer vision datasets?

I find having ResourceData/Objects for machine learning datasets to be extremely useful, with their "TrainingData", "TestData" properties: Right now there's only a handful: And even fewer for ...
45
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2answers
7k views

Object detection and localization using neural network

Four important computer vision tasks are classification, localization, object detection and instance segmentation (image taken from cs224d course): These four tasks are all built on top of the deep ...
2
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1answer
278 views

How to import Robinhood screenshots?

I use an iPhone app called Robinhood to trade stocks and I wanted to play with the portfolio with Mathematica's finance tools. So I took some screenshots of the app and I'm trying to import the ...
0
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0answers
62 views

Improved version of FindFaces [duplicate]

The built-in function FindFaces seems to miss faces a lot, for example ...
5
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1answer
249 views

How to write a RCNN (region-cnn)?

Has anyone end-to-end trained a single net that can find the location of objects in an image (with v11.1)? Here's an example of a region-cnn in action, and this is a good description of the approach.
5
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0answers
453 views

How to train a visual attention model?

In version 11.1 there is a new layer type SequenceAttentionLayer[]. I'm interested in how might this be used to train a recurrent visual attention model (see the ...
1
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2answers
101 views

What is the algorithm applied by ImageAdjust[image,{c,b,gamma}]

I want to know how ImageAdjust work to change the pixel values by specifying all parameters b,c and gamma. In openCV, the transformation is linear ...
6
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0answers
507 views

How to recognize multiple objects in an image

I'm trying to do multi-object detection and recognition using Mathematica. For example, in this image: img = Import["https://i.stack.imgur.com/lbSwV.jpg"]; the ...
14
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3answers
5k views

Nontrivial background removal

I have an image of a product on a poorly made green screen and need to segment out just the product: The problem is that it contains a mirror, so simple color-based methods are not enough. I tried ...
18
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3answers
1k views

Find lane lines

A crucial step in self-driving car is to detect lane lines. I'm wondering whether this can be achieved robustly using Mathematica's rich image processing tools. For example how can I take camera ...
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0answers
74 views

List of all valid categories for ImageIdentify? [closed]

Can anyone give me a list of valid categories for the second argument of ImageIdentify?
16
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3answers
956 views

How to place path lines on an image

I have a "sugarcane crop" image taken from above (with a Drone) which was pre-processed with the MorphologicalPerimeter and EdgeDetection functions of Mathematica, resulting in binary image with a ...
8
votes
2answers
310 views

How to detect discolorations in an image?

I'm evaluating the technical quality of an images and I'd like to scan it for defects from dirty sensors. Are there any filters to quickly detect a blob of discoloration? Here are a few examples:
24
votes
1answer
902 views

How can I detect locations of Go (aka Baduk, Weiqi) stones on a board?

The Goal There are a couple apps that score a Go board from a photo. I was wondering if something like that would be possible with Mathematica. The key step is to detect the positions of the stones ...
2
votes
1answer
405 views

How to get a full closed contour image [closed]

In this program, I need to select the point on the contour image that has the same abscissa as the center of the contour and has the highest ordinate. However, since the contour is not full closed, ...
1
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0answers
106 views

Using Classifier with NearestNeighbors methods

I am using a Machine learning toolbox on mathematica. I have 8 classes. Training data: for each class, there 100 samples with size 160. I used this code. ...
4
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1answer
980 views

How to label my training images?

I'm switching over Matlab, but I have a problem. Matlab has a GUI tool called the "Training Image Labeler" (shown below) that I use all the time to label my training data for my computer vision ...