How do I set up a for loop to replace specific pixels of a color image (with a value of 0) with specific pixels of another color image?

I would like overlap a small picture (200x300) into a specific area of a big picture (2000x2600). How would I set up a for loop to make this action take place with two color photos?

Answer 1

[Image Analyst]

Try this (untested):

% Find logical indexes of where there is 0 in image1.
zeroPixels = image1 == 0; 
% Replace them with the same pixels from image 2
image1(zeroPixels) = image2(zeroPixels);

If that doesn't work, let me know.

[Alexander Killam]

This method did not work. The issue is that the zero pixels of image 1 is not the exact size of image 2. Idk if there is a way to resize image 2 to fit those dimensions. I was hoping there was a way I would say I want to replace pixels (500-700 x 1000-1300) from image 1 with pixels (0-200 x 0-300) of image for an example.

[Image Analyst]

You can do that - that's simply copying and pasting. I've attached a demo for that. You'd have to basically adapt my demo to handle color images.

[Alexander Killam]

I tried the demo. it is very useful. Thank you. Is there any way to just copy the cropped image to a set of dimensions already known instead of clicking where to paste?

[Image Analyst]

Sure. Feel free to hard code in coordinates if you want, instead of having the user click where to paste it.

[Udaib khan]

@Image Analyst please have a look at this problem Texture mapping