How to save an image from imshow() as a .jpeg?

I am creating an RGB image and displaying using imshow(). Once the image is displayed, if I save the image as .jpeg, it gets a white background to it and the image dimensions change. How can I keep it to its original dimensions? Attached image is what I got when I saved it as a .jpeg file and the dimensions are 240x170. Whereas the original dimensions of the constituting matrices are 100x100.

Answer 1

[Walter Roberson]

Have a look at print(), which pays attention to the figure PaperPosition* properties and to the figure InvertHardcopy property. It also allows a -r resolution option.

However, I would instead recommend using imwrite of the rgb matrix.

[fiona rozario]

Thank you, once again...

Answer 2

[Dariush Ashtiani]

You can use saveas commad. Say

filename='image1'; saveas(gcf,[filename,'.jpg'])