I have data x, and y plotted it. I get an image with dimensions 30000xenter image description here14000. try saving the plot image as the same dimension but the Matlab resizes data and saves it as dimension 1366*651.
can someone share with us the idea to solve this state?
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I have a pytorch tensor image. I want to find the histogram for each channel and overlay the histogram image on top of the original image (in a corner). It would be useful if I can get the overlayed image as a tensor itself. How can I get that?
There is a longer way of doing this by first getting the histogram, save the histogram as image, read the histogram image as tensor, then replace a region of the original tensor image with the read histogram image tensor.
There has to be an easier way than this.
I have an image with 6 colors each indicating a value. I had obtained an image as shown below.
I need to smoothen the edges and then find out the area as well as the surface area of that region. The second image shows a black line drawn in the edges which indicates that I need to smoothen the edges in such a way.
I had used segmentation to create a mask as shown in the third image, and then obtain a segmented image using the code following the image.
I have used the following code for generating till the masked image.
Source : How to segment
imshow(Out1)
str = 'Click to select initial contour location. Double-click to confirm and proceed.';
title(str,'Color','b','FontSize',12);
disp(sprintf('\nNote: Click close to object boundaries for more accurate result.'));
mask = roipoly;
figure, imshow(mask)
title('Initial MASK');
maxIterations = 3000;
bw = activecontour(Out1, mask, maxIterations, 'Chan-Vese');
% Display segmented image
figure, imshow(bw)
title('Segmented Image');
In order to use the 'activecontour' function my image needs to be a grey-scale image, which I'm not being able to convert to greyscale and back. Also to find out surface area/ area of the region is there any inbuilt function. Please help thanks.
use im2double, im2uint8, etc. to convert binary image to grayscale.
use bwarea or regionprops to find the region area.
I have a problems with dimensions of the picture. It is very important because it represents a velocity structure, and so the picture I got is somehow deformed.
figure
load('newvel.dat')
v=reshape(newvel,106,14)
vt=transpose(v)
imagesc(vt) ;
I would like my picture to have ratio 106/14:7.57:1. Should I setup the axes or what? Is it possible and how?
Is it possible to display an image in multiple subplot axes, such that the image appears at the desired scale?
subplot(3,3,[1 4 7]);
%# image scaled down to fit 1 set of axes
imshow(img);
subplot(3,3,2);
plot(relevantData);
%# And so on with 5 other plots
I want to have the image scaled to either a fixed size or to fit the axes available to it, rather than to the size of a single axes.
My use case is to show a video alongside plots derived from the video, such that the plots are progressively drawn in step with the video. Once the display is correct I can save each image and combine them into a video.
Clarification
I am asking if it is possible to produce a figure as described without specifying the position of every element in absolute terms. Though one can make arbitrary figures that way (and in fact I have done so for this project), it is very tedious.
Edit:
For changing the size of the subplot:
In help subplot they mention that you can set parameters on the selected "axes" (that's what they call a plotting area in Matlab).
Using that, you can set the 'position', as seen in help axes. This property takes takes as argument:
[left, bottom, width, height]
As pointed out by #reve_etrange, one should use absolute positioning for axes 'Position'and 'OuterPosition' parameters. they can be in normalized coordinates, though.
For changing the size of the image in the subplot:
I think there are 2 useful things for you in the help imshow output:
'InitialMagnification': setting the magnification of the image.
'Parent': determines which parent imshow will use to put the image in (never tried using imshow with subplots).
I want to crop an image from a specific row onwards. Please help me how can I do this. I am a beginner in Matlab.
This page has a lot of great info on dealing with images in matlab.
When you load an image in matlab, it is loaded as a MxNx3 matrix. The third dimension stores the RGB values of each pixel. So to crop an image you simply select just the range of rows and columns you want to keep:
cropped_image = image(RowStart:RowEnd,ColStart:ColEnd,:);
See this: http://www.mathworks.com/help/techdoc/creating_plots/f9-47085.html
There is a graph editor icon in the screen where you see your graph, it should look like this:
Press it, you will get a big graph editor, now try pressing on the graph or one of the functions, in the lower right part you can set ranges, this will crop the image.
You can use imcrop function in Matlab
CropIm = imcrop(I, rectangle);
rectangle is a four-element position vector [xmin ymin width height] which indicates the size and position of the crop rectangle.
Im = imread('test.tif');
Im2 = imcrop(Im,[75 68 130 112]);
imshow(Im), figure, imshow(Im2)