part color part black and white

I have a grayscale image. I want to change some pixels to colored pixels. How do I do that? thanks

[Chaya N]

What kind of changes were you seeking to do?

Did you want to color certain areas of your image? or did you want to simply draw colored outlines around these areas?

An attached image and a few details by way of explanation would be most useful here!

Answer 1

[Walter Roberson]

You need to convert the grayscale to equivalent (gray-toned) RGB image, after which you can add color to the image.

newRGBimage = YourGrayImage(:,:,[1 1 1]);   %a fast way of copying the image to three color planes

newRGBimage(:,[1 end], 1) = 255;   %draw a red left and right border

[Douglas Brenner]

I have to parse what you did but it worked once I converted my image to uint8. Thanks.

[Walter Roberson]

Small correction:

newRGBimage(:,[1 end], 1) = 255;   %draw a red left and right border
newRGBimage(:,[1 end], 2:3) = 0;

If your image is double instead of uint8 then change the 255 to 1.0