Questions tagged [image]
Tag for questions about bitmapped graphics, particularly those using the Image function.
168
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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 ...
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3
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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 ...
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21
votes
2
answers
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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
11
votes
2
answers
654
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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
...
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14
votes
2
answers
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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, ...
- 9,455
20
votes
3
answers
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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 ...
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17
votes
1
answer
808
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How to generate a Graph from a picture of a graph?
I have a picture like this
I can get this graph's vertexes
...
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35
votes
7
answers
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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
727
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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 ...
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35
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5
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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 ...
- 505
15
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3
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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
6
votes
1
answer
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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 ...
- 56.6k
9
votes
1
answer
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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♦
- 133k
40
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7
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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.
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21
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2
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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:
...
- 30.4k
32
votes
2
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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
- 2,155
19
votes
3
answers
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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
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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 ...
- 1,409
2
votes
2
answers
534
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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 ...
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80
votes
4
answers
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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 ...
- 68.9k
21
votes
1
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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 ...
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18
votes
4
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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 ...
- 1,409
9
votes
3
answers
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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 ...
- 5,105
8
votes
3
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743
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Inconsistent image sizing with Grid and Row?
Can anyone explain why Row and Grid don't size the image correctly and consistently to 300 ...
- 13.7k
6
votes
1
answer
470
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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, <...
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2
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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
6
votes
2
answers
360
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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 ...
- 1,547
7
votes
1
answer
627
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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
19
votes
1
answer
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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 ...
- 1,113
5
votes
2
answers
177
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Problem with Raster and custom ColorTable
Context
Let me define two colour tables: (which come from brewer and xmedcom respectively)
...
- 21.7k
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:
...
- 38.3k
7
votes
2
answers
800
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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 ?
- 5,349
5
votes
2
answers
419
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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 ...
- 63.3k
2
votes
2
answers
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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
10
votes
4
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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 ...
- 264k
6
votes
0
answers
312
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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 ...
- 264k
0
votes
1
answer
729
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Reverse after ImageData? [duplicate]
Why should we do a Reverse on the image data after an ImageTake ?
For example:
...
- 1,409
30
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2
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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 ...
- 30.4k
24
votes
1
answer
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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
...
- 30.4k
21
votes
2
answers
1k
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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 ...
- 3,258
16
votes
1
answer
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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.
...
- 13.7k
10
votes
2
answers
924
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 ...
- 121
5
votes
2
answers
3k
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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 ...
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14
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1
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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?
...
- 30.4k
14
votes
3
answers
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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 ...
- 30.4k
11
votes
2
answers
1k
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Detecting edge/region in contour plot
I am interested in improving this plot:
which I produced with the following command:
...
- 21.7k
6
votes
1
answer
1k
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How to return position of one image inside of another [duplicate]
With ImageAlign result is another image, that is composition of another two.
But I'm looking for function that will find position, x-y coordinates of smaller image ...
- 900
18
votes
1
answer
403
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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 ...
- 264k
10
votes
1
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583
views
How to patch fingerprint ridges
I get a fingerprint:
But as you see,there are some place is discontinuous,such as:
The question is how to patch the discontinuous line according its gradient?The only one thing that I can think it ...
- 23.9k
7
votes
1
answer
785
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Rendering a 3D volume with Image3D
I have 2D JPEG images, of 1024 x 1024 pixels, corresponding to a 500 x 500 square micron section. These images are taken from slices of tissue, each slice seperated by 10 microns. I've been trying to ...
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