Questions tagged [image]
Tag for questions about bitmapped graphics, particularly those using the Image function.
173
questions
40
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5
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Efficiently generating n-D Gaussian random fields
I am interested in an efficient code to generate an $n$-D Gaussian random field (sometimes called processes in other fields of research), which has applications in cosmology.
Attempt
I wrote the ...
- 22.1k
34
votes
3
answers
3k
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How to place an image inside a notebook, with the minimum memory footprint?
When creating a notebook with images, like photos, the file tends to quickly get big, which makes it difficult to use the notebook format for training material containing a lot of images.
Are there ...
- 6,585
21
votes
2
answers
5k
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Failure to export graphics by right-click when Notebook magnification is changed
Bug introduced in 9.0.1 or earlier and persisting through 11.0.1 or later
When I try to export graphics as PNG, JPG and other rasterized formats using the right-click and choosing ...
- 211
14
votes
2
answers
2k
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How do I display imported images at actual size?
I know that this is an extremely basic question, but I am having a lot of trouble finding the answer in the documentation.
When I import an image (for example, ...
- 9,667
11
votes
2
answers
681
views
Using a given colour table with Image?
Context
I would like to represent large images with a given colour table.
Now, if I use Image
...
- 22.1k
20
votes
3
answers
25k
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Calculate the 2D Fourier transform of an Image
I am new to Mathematica, and using version 8.0.
I would like to calculate the 2D Fourier Transform of an Image with Mathematica and plot the magnitude and phase ...
- 399
17
votes
1
answer
867
views
How to generate a Graph from a picture of a graph?
I have a picture like this
I can get this graph's vertexes
...
- 24.7k
35
votes
7
answers
12k
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Embed Code Into Image
I often export images(plots, matrix, arrays, etc..) from mathematica which I end up putting in word documents or uploading to the web. The problem is that I often lose the original code and I am left ...
15
votes
3
answers
771
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Deleting noisy data from a plot (manually) and export the best remaining data
I have the following temperature time-series. As you can see it contains very very noisy points in some periods (Fig.A). I tried to approach the best data(the black one in the center) based on the ...
- 507
36
votes
5
answers
13k
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How can I detect an ellipse in a photo?
I tried to detect the rim of the following cup as an ellipse.
I've tried the solutions given in How to find circular objects in an image? to detect the ellipse, but the detection result was not quite ...
- 515
33
votes
2
answers
2k
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How to project 3d image in the planes xy, xz, yz?
Some idea of how to do something similar to the image, but with any 3d object
- 2,185
23
votes
1
answer
1k
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Why in Mathematica 13 do imported PDFs have lower image quality?
I'm finding images imported into Mathematica 13 notebooks are noticeably pixelated. (Oddly, pasting an image into a notebook cell does not have this problem.) Has the default changed for some import ...
- 12.9k
15
votes
3
answers
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Line Intensity Profile From Image
I can get line profiles from images using imagej but it would be nice to be able to do this in my mathematica notebooks.
I found this
http://library.wolfram.com/examples/intensityprofiles/
after ...
- 383
9
votes
1
answer
340
views
Transparent bitmaps or graphics in gui objects initially appear wrong
Bug introduced in V9.0 or earlier and persisting through V11.3
I have a problem with images with alpha channel which I want to use as labels on Button etc. Unless ...
Kuba♦
- 134k
6
votes
1
answer
303
views
Is it possible to render Graphics with more than "Byte" bitdepth?
I wonder is it possible to render Graphics in Mathematica with bitdepth higher than "Byte" which is the maximum bitdepth ...
- 60.7k
41
votes
7
answers
2k
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Voronoi diagrams for generators other than points
Any suggestions on how to determine a Voronoi diagram for sites other than points, as e.g. in the picture below?
The input is a raster image.
- 787
21
votes
2
answers
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How can I detect a rectangular region of interest in a picture?
Here is a downsampled input image I converted to greyscale.
To select the rectangular region of interest we first preform preprocessing:
...
- 30.6k
19
votes
3
answers
8k
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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 scan....
- 3,708
13
votes
3
answers
2k
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Best method to find variation in width along the image of a slit?
EDIT: Solutions by @Alexey Popkov and @Vitaliy Kaurov are very intuitive and both can be used to find a solution for the task.
I have a slit of 15-18 microns by 1 mm projected with magnified 4X onto ...
- 1,419
2
votes
2
answers
550
views
Lossless TIFF or PNG export
I'd like to export an output from MatrixPlot[], however, the output file size seems to depend on my specification of the ImageSize -> {..., ...}. How might I export a TIFF with all of the data in the ...
- 55
80
votes
4
answers
16k
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Programmatic approach to HDR photography
Update
Submitted answers here are tour de force, and very educational comp-sci-wise, -- thanks folks! Tech is developing though, and here is the current implementation in the Wolfram Language. Please ...
- 69.8k
21
votes
1
answer
3k
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How to extract metadata from an image of a business card?
I'm trying to digitize some documents, and I came across a very cool app called camscanner app which performs parallax transform and ocr very nicely, now I'm implementing it in mathematica...
Given a ...
- 30.6k
18
votes
4
answers
3k
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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 in ...
- 1,419
15
votes
3
answers
6k
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 ...
- 30.6k
11
votes
2
answers
276
views
Magnifying the Help documents without magnifying the images therein
In Mathematica's Option Inspector I set the notebook magnification factor to be larger than 1, for example 1.12 ("Notebook Options"->"Display Options"). Accordingly contents of the Documentation ...
- 882
9
votes
3
answers
995
views
How can I capture a rectangular area from an image?
I am looking for a method to extract rectangular areas from an image. The image is divided up into rectangular problem spaces like the image shown below. Each numbered problem is given with some text ...
- 5,125
8
votes
3
answers
787
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 ...
- 13.8k
7
votes
1
answer
657
views
How to increase the image resolution of a map?
I'd like to obtain higher-resolution geographic maps retrieved from Wolfram geo server, since the standard resolution seems poor.
I tried to increase the "TileSize" parameter, like this:
...
- 710
7
votes
2
answers
377
views
Force size in pixels of plot area excluding axes and labels
I have a matrix where each element represents a pixel. I want to plot the matrix (possibly with ArrayPlot). To suppress aliasing in the final graphic (which I will ...
- 1,557
6
votes
1
answer
485
views
HOWTO encode/decode large chunks of Mathematica code/results e.g. for posting on sites?
At times, we as questioners would like to post huge Mathematica-expressions to websites (e.g. mathematica.stackexchange.com), or have an easy way to get such code from a site. Above a certain size, <...
- 3,685
6
votes
2
answers
4k
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How can I put an image on a surface [duplicate]
I want to paste an image on the surface of a 3D plot. For example consider this image which I want to paste on the surface of this sphere
...
- 111
19
votes
1
answer
2k
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Slow import of multigigabyte TIF image stacks
Update 6: After contacting Wolfram Technical Support, I was advised that the frame-to-frame import timing variability can be eliminated by reading in the frame stack from frame to frame with the ...
- 1,123
10
votes
1
answer
1k
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transparency in image used for texture?
Is there a way to set a transparancy channel in a raster image used for a texture in 3d graphics?
this creates a raster image with a transparency channel:
...
- 38.6k
10
votes
4
answers
403
views
Why do quote marks appear in output when saved with Save Selection As?
Update #2: This behavior has been confirm across platforms and in multiple versions. Therefore:
Is this a bug or a feature?
Can I disable this "feature" so that copying a selection of Cell contents ...
- 266k
7
votes
2
answers
829
views
Rectangle with rounded edges
Inspired from :
Fit an image within a Rectangle [] in Graphics
I would like now to fit an image within a Rectangle[] with rounded edges as shown in the example below :
Is it possible ?
- 5,439
6
votes
0
answers
312
views
Bug report: Attempting to Save Selection As... in a magnified Notebook fails with errors [duplicate]
Bug introduced in 9.0.1 or earlier and persisting through 10.0.2 or later
I have found that attempting to Save Selection As... in a magnified Notebook fails with errors.
On my system it can be ...
- 266k
5
votes
2
answers
182
views
Problem with Raster and custom ColorTable
Context
Let me define two colour tables: (which come from brewer and xmedcom respectively)
...
- 22.1k
5
votes
2
answers
428
views
Cannot change ImageResolution after applying ImagePad [duplicate]
I want to export high-resolution images of a plot I'm making. The trouble is, the plot has a lot of extra white space around it which I get rid of via ImagePad (I ...
- 65.5k
2
votes
2
answers
1k
views
Importing a Canon Raw file (.CR2)
This is a very top level question with no code examples attached. I have an interest in using Mathematica to read raw files coming from a Canon camera, before they are converted into jpg's, where ...
- 145
0
votes
1
answer
752
views
Reverse after ImageData? [duplicate]
Why should we do a Reverse on the image data after an ImageTake ?
For example:
...
- 1,419
30
votes
2
answers
8k
views
How to automatically remove text from images?
I'd like to remove the text in the center of images automatically. To use Inpaint[], you need a mask, but I don't have one. So really the problem is:
How to build ...
- 30.6k
24
votes
1
answer
5k
views
How can I detect if an image is of poor quality?
I need to filter out blurry or otherwise bad quality images from a set. I would like an efficient method to detect images that have any of the following three attributes:
Out of focus or motion blur
...
- 30.6k
21
votes
2
answers
1k
views
Why does ImageData need four times more memory?
Background
We are dealing with very large TIFF image files that are imported, processed and exported using Mathematica 9.0.1. Many of our algorithms only work with an array representation of the ...
- 3,298
19
votes
1
answer
996
views
When exporting an (animated) GIF, is it possible to specify the size of the color palette?
I've exported an animation to animated GIF, which generated a 15mb file. I've been asked if I could regenerate the file, limiting it to only 16 colors, but I can't find any documentation on how I ...
- 3,129
18
votes
1
answer
413
views
Color degrades when using Copy As Bitmap
I have discovered a problem that affects my use of Mathematica. When I use the menu command Edit > Copy As > Bitmap the colors in the copy are subtly degraded. To make this more apparent I copied ...
- 266k
16
votes
1
answer
3k
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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.
...
- 13.8k
14
votes
1
answer
949
views
How to implement a free version of WebImageSearch?
I really don't like functions that I have to pay for, if they can be implemented for free.
Is there a way to get around this pay-wall for WebImageSearch? Perhaps using some other free api or service?
...
- 30.6k
14
votes
1
answer
243
views
"Boundary" thickness in HighlightImage
Bug introduced in 11 or earlier and persisting through 11.3
CASE:4076121
I'm having a hard time to understand how I can use HighlightImage and only draw the ...
- 112k
13
votes
1
answer
274
views
What governs images resizing in the FrontEnd environment
What is responsible for the middle Row images' size? And why single image row is different?
...
Kuba♦
- 134k
11
votes
2
answers
1k
views
Detecting edge/region in contour plot
I am interested in improving this plot:
which I produced with the following command:
...
- 22.1k