Questions on the image processing capabilities implemented in Mathematica.

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13
votes
3answers
3k views

Composing an image with a plot

I'm trying to illustrate the solutions to a textbook problem dealing with quadratic functions. This will involve plotting a quadratic and overlaying the plot and the image. Here is the textbook ...
10
votes
1answer
3k views

Image Processing: Finding Orientation and Position of Symmetry Axes

Background I'm currently toying with Principles of Design by Charlotte Jirousek in order to learn some basics of image processing. As main principals she suggests Balance, Proportion, Rhythm, ...
13
votes
3answers
625 views

Image Processing: Concrete test blocks

Background Concrete is mixture of aggregates and cement. Aggregates are composed of different sizes and colors. Core samples are taken by drilling in order to test the strength of concrete . They are ...
12
votes
1answer
497 views

Precise cropping with ImageCrop

The built-in ImageCrop function "effectively removes borders from image whose pixel value distribution is almost uniform" (emphasis mine). I need an efficient ...
10
votes
4answers
903 views

Image correlation

I have two images from motor scan, Image1 is shifted by MxN pixels from Image2. How can I find the shift between Image1 and Image2 ? Image -1 Image -2 If we compare the shift between the images ...
19
votes
1answer
2k views

Finding the area, algebraic curve and jaggedness of an arbitrary shape

I start with a photograph of a shape (physically made by the flow of a liquid into another), of which I can extract the border, manually or using Mathematica's feature detect feature : Using the ...
12
votes
3answers
810 views

Image levels: how to alter 'exposure' of dark and light areas?

I was working with some less than ideal photographs, and wanted to adjust them before continuing. I wanted to raise the levels of the very dark areas and lower the levels of the very light areas. I ...
8
votes
6answers
284 views

Coloring an image with two Color schemes based on a Range

I would like to color an image generated from some data, using two color schemes based on two ranges of the data. This is my attempt: ...
12
votes
3answers
4k views

Saving high-quality graphics through commands

Say I make and display a graph in a Mathematica notebook: graph = CompleteGraph[100] If I drag the corner of the graph to increase its size, and then save it to ...
11
votes
1answer
1k views

Implementing OCR without using TextRecognize

I am new to Mathematica and trying to figure out whether it is a good tool for algorithmic exploration. So I had the idea of implementing a simple OCR with Mathematica, just using standard ...
6
votes
3answers
605 views

Opacity and overlapping multiple polygons

Let's say I have 100 polygons that are all different but most of them overlap. All I want to do is to draw/plot them in one single graphic with linearly adding gray values; i.e., a point with ...
5
votes
1answer
610 views

How do I put an image on the complex plane?

I watched this video and became interested in transforming an image. But I have no good idea on how to embed an image in the complex plane using Mathematica. I have a method that seems to work, but ...
54
votes
5answers
10k views

How to create hedcut style images?

Yesterday the hedcut style was brought up in chat. How can we create a hedcut-like style automatically in Mathematica, using a photograph as a starting point? I am looking to create a similar ...
31
votes
3answers
2k views

xkcdConvert routines perform slower in Mathematica 9

I am experiencing some rather large performance decreases in Mathematica version 9.0 using the xkcd-styled plotting routines. I had used the xkcdConvert code ...
24
votes
3answers
1k views

Finding a function that fits the shape of an image

How can I find a function that fits the given shape of an image? Or instead extract a point set from the shape and then find an interpolating function fits the shape. An example image is attached.
29
votes
4answers
2k views

Clustering of space-time data

Below is an example of a gaze sequence I recorded during a 3 seconds display. That is, where the eye was at every millisecond. While we should have 3000 points, we are missing some due to blinking. ...
23
votes
3answers
2k views

Data fitting with Image processing feature detection

I have some 2D data that once plotted looks like the following ...
15
votes
6answers
2k views

How to find major color in a picture?

I want to find the major color (the color which appears most often) in a picture and do some analysis later. For example, if I have this picture: What I want to do is find out that gray, red, ...
14
votes
2answers
2k views

How to convert an image to a graph and get the positions of the edges?

I am trying to convert an image to a graph. My image is already skeletonized and looks pretty much like this: What I need to do is identify all vertices and edges, and in particular get a list of ...
12
votes
2answers
1k views

Image Processing: Isolating areas of an image with internal irregularity

I am trying to isolate each of the blue painted fingernails in the image. However, I am not sure what approach should be considered due to the white design on each nail interrupting the otherwise ...
11
votes
4answers
2k views

How do I find the coordinates of points in this image?

I have never used image processing with Mathematica. I need to get the coordinates of the red points from this image I made in Illustrator. Is there a way to get Mathematica to read or detect the ...
7
votes
2answers
419 views

Band Intensity Quantification

I would like to measure the density of my western blot band by measuring the area under the peak from this plot. More specifically, my image will have several lanes with a pattern of bands in each ...
13
votes
1answer
1k views

Enlarge an image and increase its resolution

An ongoing purely recreational project. I got my introduction to image processing with this Rotating perspective... question and had a lot of fun with it. Now I want to take it to the next step. ...
24
votes
3answers
2k views

How to find the center of a circular pattern?

I am writing an algorithm that finds the center of 500 x 500 pixels images coming from a live feed from a camera at 50 Hz. So it has to be quick! The images are images of an optical field which looks ...
19
votes
2answers
691 views

Improve TextRecognize[] on numbers

I have an image contain only numbers, and TextRecognize fail to recognize some numbers: img=; TextRecognize[img] (*826718*) The documentation says that "The ...
17
votes
3answers
2k views

How can I efficiently “remap” an image?

Many image processing libraries like OpenCV, Intel Performance Primitives or Octave have a useful function called "remap", that takes an image, an array with X coordinates and an array with Y ...
23
votes
3answers
1k views

Download xkcd Click and Drag comic

Inspired by the recent question about xkcd styled plots I started looking at xkcd again and I came across a comic titled Click and Drag. And if you do that, you start exploring a larger drawing. A ...
20
votes
2answers
566 views

Convert binary voxel image to geometric region

I have a binary voxel image which described a contiguous region in space. Example: ...
15
votes
4answers
1k views

What is the fastest way to locate an image inside a larger image?

let b = let c = How to do: find[c,b] that returns the bounding box of c in b? ...
3
votes
2answers
1k views

Generating x,y coordinates for an edge detection

I'd like to be able to process a number of graphics that have edge contours and output a list of $x$, $y$ coordinates to be used for generating a spline in another program, or in Mathematica, to make ...
18
votes
3answers
2k views

Filtering pixels of a certain color

What is the best way to filter an image so that only the pixels close to a certain color are left? I've downloaded some satellite images from the web where a specific pixel color corresponds to a ...
20
votes
3answers
2k views

Finding the centroid of a disk in an image

I got about 100 images of the sun and have to find the centre of the star in the images. I have binarized the images and used ComponentMeasurementsto find the ...
17
votes
2answers
799 views

Extracting angles from a simple picture

I'm not sure if this is even possible with Mathematica, but I want to extract the angles between all lines in this picture: It consists of $12$ lines, so I want a matrix with $144$ entries. I ...
13
votes
3answers
834 views

Rotate a grid, made up of lines, so that it aligns with the xy axes

While working on an answer for another problem I hit upon one of my own. I took the image given in that question and cleaned it up so that I could detect the grid lines: ...
12
votes
1answer
1k views

Copying an image from the clipboard, modifying it and returning it to the clipboard

I have a Mathematica script to help me copy images from PDFs and then make the (presumably white or nearly white) background transparent. Typically, I am looking at the PDF in Adobe Acrobat and I ...
4
votes
3answers
240 views

Inconsistent image sizing with Grid and Row?

Can anyone explain why Row and Grid don't size the image correctly and consistently to 300 ...
10
votes
2answers
2k views

Overlapping accurately Images and Graphics (without loss of resolution)

Context In a previous post, I learned how to produce these kind of plots, which are of interest in astrophysics and geophysics. I am now interested in combining them. Attempt For this purpose, ...
10
votes
1answer
2k views

Construct 3D image from multiple 2D images

My goal: How to (1) construct 3D image for visualization. (2) how to write 3D array or image into binary raw file. Is there a way to accomplish this in Mathematica? Alternative_Answer for: ...
8
votes
1answer
558 views

Counting elements which are inside another element on a different colour channel

I have a 3-channel image which shows red and green points (certain labelled proteins) inside blue regions (cell nuclei). After applying some segmentation filters, the resulting image is as follows: ...
7
votes
1answer
454 views

Calculation of 2D FFT for an image

I am trying to obtain 2D FFT of an image. From the 2D FFT, I wish to calculate the amplitude of the FFT averaged over a circle vs the distance in pixels by varying the radius of the pixels which is ...
5
votes
1answer
186 views

Trace one point's coordinate values in sequentially images

I am a research student in a university. I think I need some help. I used a video camera to monitor the vibration of a plank. Then I should calculate the amplitude and frequency of the vibration ...
0
votes
3answers
539 views

Derive a smooth circle with cusp from an image

question 1 get the center (sample data) sample is the black circle with cusp. ...
12
votes
2answers
1k views

Detecting an ellipse in a glaucoma photo

For glaucoma diagnosis it is common to determine a "cup to disk ratio" which compares the diameter of the optic disk (VDD) and optic cup (VCD). The optical disk is visible as a circular red feature ...
7
votes
2answers
214 views

Apply ColorFunction to an Image [duplicate]

is there a faster way to change the colors of an image from grayscale to something like this: ...
6
votes
2answers
725 views

Fit an image within a Rectangle [] in Graphics

Based on the following Code (yet the white text in the image is added with PPT), I would like to have an image fit within one of the rectangle. For Example the image from there : ...
5
votes
2answers
653 views

Labelling objects in a picture with numbers

I need help processing a biology bacteria picture. I just started learning Mathematica and I hope you guys can use a simple method to help me solve the problem, please do not use super complicated ...
2
votes
1answer
190 views

Importation multiple dcm images [duplicate]

I'm extremely new to Mathematica. I want to import 201 .dcm (DICOM) files into Mathematica 9. Is there a way to do this which doesn't require my doing it an image at a time? My ultimate need to is to ...
7
votes
3answers
344 views

Coloured image transformation in pointillism

I would like to transform an image (a photo for example) into a set of single colour circles with fixed but adjustable diameter (bigger than the pixel size), into a kind of pointillism. The number of ...
6
votes
1answer
362 views

Removing gutter shadows from scanned pages

I am new to image processing, and I was hoping someone might set me in the right direction. I am trying to create a simple toolkit for personal use for digitizing scanned book images into a database. ...
5
votes
3answers
510 views

Tile image on specific location without space between them [duplicate]

Possible Duplicate: How to combine images with the same dimensions in a grid? I would like to arrange images without any space between their edges as each piece is made to connect with ...