All Questions
Tagged with fitting image-processing
21 questions
4
votes
1
answer
188
views
Using mathematica to find the equation of curves, by providing images, providing constraints, or both
By "collaborate", I mean to give some instructions or constraints.
Consider the following curves: (as examples, only to illustrate my question in a better way):
Curve (I): Assume it is f ...
- 336
1
vote
1
answer
190
views
Fitting an Equation to an Image
I'm very new to data analysis and I'm trying to figure out how I can fit an equation to an image I generated from a large set of data I collected. I'd then want to overlap this plot to the image to ...
- 51
2
votes
1
answer
199
views
How do i plot a graph for width vs height of the slits from an image
I need to calculate the width of the slits along the length of each slits. I am new to image processing in mathematica and I need to plot a graph showing how the width changes along the length.
I have ...
- 21
5
votes
2
answers
577
views
Fit ellipse to a arbitrary 2D image to extract centroid, orientation, major, minor axis
I am wondering if there is an easy way to fit an ellipse into an arbitrary 2D image quickly, so its centroid, orientation, major, and minor axis length can directly be extracted. In MATLAB, this can ...
- 105
10
votes
2
answers
2k
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How to fit a curve in a picture with an equation?
For a curve taken from a picture, is there any method to fit it with an equation if it appears to be some standard curve?
For example, in the following picture, the curve looks like an ellipse or a ...
- 823
1
vote
0
answers
136
views
NonlinearModelFit with two-dimensional input to two-dimensional output
I want to estimate a nonlinear mapping from two-dimensional input positions to two-dimensional output positions. (Think of this as a nonlinear distortion of an image. Once I get the estimated ...
- 42.3k
1
vote
1
answer
274
views
Fitting a slanted edge using error function
I am trying to fit a function to my data that looks like the image below. This image is a slanted edge that is kept at an angle $a$ w.rt. the y-axis. For this, I am using the error function (Erf[]) in ...
- 371
6
votes
2
answers
655
views
Fit a circle to a region of an image
I would like to develop a routine that associates a size with images such as that below. My idea is to find the radius of the circle (centered at the origin) that contains (say) 95% of the total ...
- 3,436
2
votes
3
answers
405
views
How to fit implicit function based on an image in mathematica?
I know how to make a plot given a function, but I don't know how to get implicit function based on an image.
For example, I have the image shown below (thumbnail):
Full size image import:
...
- 707
16
votes
2
answers
563
views
Fitting Stradivari's scroll
How can I find the simplest curve that gives me a scroll like this?
This is where I am at the moment and doing it by hand is becoming more and more cumbersome.
First, take a drawing of the scroll ...
- 2,671
14
votes
5
answers
2k
views
Fit image of mountain to gaussian
I want to detect the edges of an image of a mountain and then fit that to a gaussian.
I am unsure about how to only get the mountain edge, rather than every single edge in the image.
How do I ...
- 2,274
15
votes
2
answers
1k
views
Fitting a curve to an image object: not a superellipse, not an egg curve.. what else?
I'm facing the problem of quantifying the morphology of objects with such a shape (nannoconids...
they are fossils).
One of the final goals is to produce a solid of revolution and compute volume/...
- 331
0
votes
2
answers
828
views
Getting image data values with coordinates in circular region
I have a number of gray level images (600, with size: 2400x2400 pixel, small instance see above). In this image there is a circular region of interest. The aim is to fit a function to the gray value ...
- 1,590
13
votes
2
answers
2k
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 (...
5
votes
2
answers
371
views
How to find analytical expresion for data from image
I need to find an analytical expression for the data collected from an image.
I found a relevant topic on how to extract the data in here.
But there are some differences in my question.
I have this ...
- 27.2k
5
votes
2
answers
4k
views
Best fit equation from a scanned image
I am trying to extract a curve from a scanned graph and find a best fit equation. For example, starting from:
How could one find an equation starting from the image file ?
- 1,725
10
votes
1
answer
3k
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Measure length and diameter of objects in an image
I am new to Mathematica, and I am trying measure length and diameter of rectangular objects in an image. I wanted to fit rectangles in the objects, and then get the values.
Can I do that with ...
- 101
18
votes
4
answers
27k
views
Fitting a two-dimensional Gaussian to a set of 2D pixels
Imagine I have a set of data like the following:
...
- 761
2
votes
1
answer
413
views
non-linear trend reduction using thresholds
Doing some mappings of the earth magnetic field results in the left-hand figure below (which consists of 181 profiles):
To improve this I tried a non-linear trend reduction using, for example,
<...
- 1,583
20
votes
1
answer
3k
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 ...
- 303
23
votes
3
answers
3k
views
Data fitting with Image processing feature detection
I have some 2D data that once plotted looks like the following
...
- 14.9k