How to save a plotted pattern onto an image?
I am trying to save an image with a circle drawn on it. I tried with both imwrite and print, but then when I open the file again, the plotted circle is gone. Image = imread('Eye_00001.jpg'); figure('visible', 'off') imshow(Image) % plot circle (CRx and CRy are center coordinates, CRr is radius) hold on th = 0:pi/50:2*pi; xunit = CRr * cos(th) + CRx; yunit = CRr * sin(th) + CRy; plot(xunit, yunit, 'r'); % plot the circle center scatter(CRx, CRy, 20, 'r+'); hold off % save the image: save_file_name = strcat(working_directory_name, 'Eye_res_00001.jpg'); imwrite(Image, res_filename) close(figure) The version with print changes in the lines: save_file_name = strcat(working_directory_name, 'Eye_res_00001'); print(res_filename, '-djpeg') Is there something I'm getting wrong?
Prashant Kumar answered .
2025-11-20
Image = imread('Eye_00001.jpg');
figure('visible', 'off')
imshow(Image)
% plot circle (CRx and CRy are center coordinates, CRr is radius)
hold on
th = 0:pi/50:2*pi;
xunit = CRr * cos(th) + CRx;
yunit = CRr * sin(th) + CRy;
plot(xunit, yunit, 'r');
% plot the circle center
scatter(CRx, CRy, 20, 'r+');
hold off
F = getframe ;
% save the image:
save_file_name = strcat(working_directory_name, 'Eye_res_00001.jpg');
imwrite(F.cdata, res_filename)
close(figure)
To save a plot using interactive controls, use the export button 
in the axes toolbar. The toolbar appears when you hover over the upper right corner of the axes. The export button supports three image formats (PNG, JPEG, and TIFF), as well as PDF files, which can contain images or vector graphics, depending on the content in the axes.
For example, create a bar chart. Save the chart to a file by hovering over the export button in the axes toolbar and selecting the first item in the drop-down list
When you use the export button to save a plot, the output is tightly cropped around the axes content, including any legends or colorbars. The output does not include content outside the axes, such as other axes in the figure.
If the figure contains multiple plots in a tiled chart layout, you can save all the plots together by moving the toolbar to the layout. To move the toolbar, call the axtoolbar function and specify the TiledChartLayout object as an input argument. Then hover over the export button in the toolbar. The toolbar appears when you hover over the upper right corner of the layout
