Change all colors in an image except black

[Hercuflea]

Hello,

I have a typesetting software which can export typeset math as normal, nice looking black LaTeX text. However it always puts it on a white background. How can I change the background color of an image (png or jpeg) without changing the black text contained int he image? Should I write a script that can do this or is there already a tool to do so? I want the background of the picture to match the background of my poster.

Thanks

 

[Borg]

It's possible to set the background of a jpeg to be transparent. I don't know what the capabilities of your software is though.

 

[jedishrfu]

Imagemagick may help, its a collection of command-line tools to manipulate image files of many types:

http://www.imagemagick.org/discourse-server/viewtopic.php?t=18196

 

[Hercuflea]

I was thinking of writing a program to cycle through each pixel and convert it to the color I want, skipping the black pixels, but I don't know if that is overkill or if there is some other easy way to do it.

Edit: cool...I will check that out

 

[CWatters]

Some programme have a "magic wand" feature that will find all regions that match the pixel selected..

http://graphicssoft.about.com/od/paintnet/a/magic-wand.htm