Questions on the image processing capabilities implemented in Mathematica.

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11
votes
0answers
154 views

Segmentation of sunspots

I recently went for a walk with my camera and snapped a few pictures of the sun. The pictures didn't turn out too well, but this was to be expected without a telescope. I thought it might be a nice ...
9
votes
0answers
338 views

Proving (self) similarity with Mathematica - Reccurrence Plots, Similarity Plots etc

I posted this question in math.se but given the sheer tumultuous number of questions that keep appearing on math.se and also given that I am trying to accomplish this in Mathematica, I thought I'd ...
7
votes
0answers
301 views

Cluster a signal into areas of equal intensity

Introduction I have a greyscale photograph that I want to partition into areas of equal intensity. This means, that the integral over each partition should be (roughly) equal. There is no unique ...
5
votes
0answers
83 views

Ways to overcome failure of TextRecognize on relatively simple price tag?

I would like to perform OCR on this sample image. TextRecognize[Import["RedBox.jpg"], Language -> "German"] returns ...
4
votes
0answers
129 views

Multi-Camera streaming using Mathematica

I am attempting to capture dynamic streams from multiple usb webcams using only mathematica. Using ImageCapture["Device" -> $ImagingDevices[[x]], I've tried to ...
4
votes
0answers
132 views

Challenge: Speeding up MaxDetect for application in 3D blob detection

In image segmentation it is a common problem that objects appear clustered and are therefore undistinguishable from each other when using simple algorithms. Based on this post I obtained efficient ...
4
votes
0answers
667 views

computation of gradient vector field in 3D using GradientOrientationFilter

I want to compute a 3D gradient vector field of an Image3D object using the built-in GradientOrientationFilter function in Mathematica. From the documentation I ...
4
votes
0answers
513 views

looking for a generalised Hough Transform function or a least a function to locate circles

I am looking for a generalised Hough Transform function or a least a function to locate circles (position of center and radius) in a image. There is the standard Hough line search function ...
3
votes
0answers
56 views

Efficient image stacking

I have a list of lists of images that I would like to stack and create mean images for each list of images. Images are .jpg files 2592x1944 pixels large. Each list ...
3
votes
0answers
61 views

How to determine foci colocalization in a microscopy RGB image

First of all thanks to everyone for the amazing amount of info and help provided here, I'm quite new to Mathematica so probably this is a very simple question but I'm not sure how to proceed. I have ...
3
votes
0answers
145 views

FindPeaks with noisy data

I am trying to understand the FindPeaks function in V10. I have two questions. Here is some measured data with noise. ...
3
votes
0answers
299 views

Masked Image Registration/Alignment/Correlation

I'm trying to register (align) two circular grayscale images using a boolean mask to prevent them simply being aligned on the fixed circular border. There are also small fixed circular regions in the ...
3
votes
0answers
314 views

How can I create jpeg images of a given file size?

Cross-posted at Wolfram Community I would like to have a function makeJPG[megabytes_] that generates random jpg images of given file sizes with itf filesize (in megabytes) watermarked on the image ...
2
votes
0answers
73 views

How to make Distance transform invariant to scale

I am using distance transform as a descriptor to encode silhouettes in order to do shape recognition task. It is clear that distribution of distance transform is invariant under rotation and ...
2
votes
0answers
104 views

Reading grave stone letters in an image

(Click on image to enlarge) (Click on image to enlarge) Is there an image processing technique that would aid in reading the letters and numbers on a grave headstone? Most stones are etched ...
2
votes
0answers
257 views

Understanding “IntensityData” coordinates

Update - Playing around a bit, is it true that we need to process the list of "IntensityData" values $r$ as follows: r = Partition[r,k]; r = Transpose@r; And ...
1
vote
0answers
63 views

Restoring an out of focus image

Folks, I am studying ways to deblurring an image: Sample: , an my goal is the money in that hand. Is possible improve the image, features, etc..? I tried all the de blurring methods: 1 - first I ...
1
vote
0answers
57 views

How can I detect certain letters by shape in an image?

I have a website where people can post Flipbook animations, called Flipnotes. Unfortunately, most of the Popular flipnotes are in the following categories: MV (Music Video) AV (Audio Video) AMV ...
1
vote
0answers
51 views

How to get the SIFT features of an image?

According to the documentation, the function KeyPoints[] computes features only using SURF, but what about SIFT or FAST features?
1
vote
0answers
58 views

Import a web page with $\LaTeX$ code including images (png or other)

To be brief; I would like to import a web page, so I use Import["http://fabricebaudoin.wordpress.com/2012/10/25/lecture-32-the-malliavin-derivative/"]; which ...
1
vote
0answers
61 views

Understanding the use of GradientOrientationFilter to achieve a “brushed” effect

I'm trying to recreate in javascript a piece of code that appeared here on Mathematica, specifically in this answer: http://mathematica.stackexchange.com/a/39049/21482 The user Simon Woods suggested ...
1
vote
0answers
77 views

stacking images

I would like to take a series of night sky photographic images taken sequentially and enhance dim stars in a single image. This is a standard function in astronomical image processing packages, but I ...
1
vote
0answers
166 views

Speeding Up Image Processing Functions

I am working with stacks of 1024x1024 timelapse microscopy images that I am performing a series of image processing functions on to help segment each image. These functions include ...
1
vote
0answers
135 views

How can I add drop shadows to the text of non-input/output cells?

Inspired by simon woods's wonderful shadow function, I want to add drop shadows to all the text of non-input/output cells in a notebook, something like this: By using simon woods's shadow function, ...
0
votes
0answers
36 views

Automatic measurement of components in a picture

I have a tricky problem, with which I'm stuck just after a few steps. I have the following picture of a slice of the brain. I want to detect all the named structures and measure the area of those ...
0
votes
0answers
36 views

Using ImageCompose with Large Images

I am trying to use ImageCompose to overlay large images. The images are too large to manipulate in memory. I am familiar with ImageFileApply and ImageFileFilter to work with images on disk, but I do ...
0
votes
0answers
65 views

Using 2D Fourier transform of an image to detect typical wavelengths

I am new to Mathematica, and I have read this post to understand how to perform Fourier transform on an image. My mission is to extract information on the typical distance between the black patches in ...
0
votes
0answers
39 views

When using Classify[] on images, is preprocessing necessary?

If the images in the training data set have different sizes and channels and color spaces, will this hinder the classifier? The examples in the documentation seem to suggest that normalization with ...
0
votes
0answers
49 views

Modulation voice

Good day I deal with an example where I want to modulate (skew) voice. After importing the voice, I did DFT, and then I want to shift the spectrum, but I do not know how to use it. Could anyone ...
0
votes
0answers
68 views

spherical histogram for 3D object

I want to develop a shperical histogram for 3D object. Given a 3D object, I put it in a cylinder where its axis pass through the centroid of the object. The cylinder is sampled into a number N of ...
0
votes
0answers
50 views

Using OpenRead to read an element from a list saved in .mx format

I have a set of large arrays 1D (1-2 million entries) where each element corresponds to a pixel value from a picture. I would like to know how a pixel value changes from image to image (how the value ...
0
votes
0answers
64 views

Expecting an image or graphics instead of -Image-

Here's a snippet of my notebook. When run with the frontend, the code runs fine with no problem at all. However, when I save the notebook as .m file and run it using "Mathkernel -noprompt -script ...
0
votes
0answers
43 views

Can any function give a draggable closed curve on feature edge of an image like “EdgeDetect” found?

I've posted the question, but hardly describe it clearly, now let me show it this way: I don't know the algorithm for "EdgeDetect". Suppose the detected image edge consists of single line pixels at ...
0
votes
0answers
73 views

GraphicsGrid command

When we merge some colorful plots to a single image, with the command GraphicsGrid, the quality of output image will be lost, slightly. That is, for instance all ...
0
votes
0answers
126 views

Change size of a saved plot or image (post-processing)

I have many plots (that take a long time to run) and each is saved to a variable name. For simplicity, say one was: ...
0
votes
0answers
111 views

Correctly set up FindMinimum

I am trying to setup the following minimization to align two astronomical images. ...
0
votes
0answers
436 views

Metric Parameters such as Pratt Figure of Merit (Pratt-FOM) for Edge Detection

I have developed a new algorithm in Mathematica v9.0 for the Edge Detection and want to compare it with the existing Roberts, Sobel, Prewitt etc, operators in the presence of Noise. I have evaluated ...
-1
votes
0answers
43 views

What is the fastest way to implement sliding windows?

I need to make a laplacian pyramid and run my feature matcher over subwindows of my image at different scales for size invariance. So what is the fastest most efficient way to iterate my code over ...