Open the file, go file/save as, select gif. this will bring up the gif export options, select the 'image color' transparency option, with the pick tool select the background color you want to be transparent and hit ok.

Hope that helped.

May I ask the same question?  I've been trying ( I give up after half an hour usually ) for years to figure this out. I currently have a company logo for a client which consists of three letters in a set of concentric boxes.  Boxes and letters are black, the background is white.

I can save the file as a GIF however in the final part of that process where I change the 'transparencey' from none to image color I'm lost.  None of the choices seem to match the 'white' background of the BMP file.  I can not get the eye dropper to sample the background ( if that is what it's supposed to do? )... I've tried applying a mask to the letters and boxes however in this final 'GIF Export' step under Transparency  only the None and Image Color choices are selectable.  The Help file says I should be using image color but now when/how to sample the background so I may assign it as the transparent color...

Could anybody point me in the right direction?


Thanks


           Paul

@Bluewale CA

First of all, after you open the image/pic, just change your image mode, on the Menu bar click image > mode and choose the RGB color (24Bit), thats the way to enable all color you want. Currently it must be saved as Paletted (8 bit) as you saved it in *.Gif format.

Now, as your image/pic is already in RGB color mode, mask the area you want. Next step, click on Mask (on toolbar) and choose "invert". Then you'll see the oposite areas in your pic are masked (not the area you want to be your image), That's it, that one will be the background.

Next step, just fill it (the area that now is masked) with any color you want as the backround. (This step the crucial point, coz it will make the match color you want appears when you export/save your pic as Tranparancy Gif image). Dont use the fill tool(bucket) on tool box bar on the left side, just click fill from Edit on menu bar (Edit > Fill) coz it fill the area with tolerance = 100% as its default).

After the step, now that area is filled with the color you want to be the background color.

Next Step, click mask on menu bar and invert it again, It will make the mask area back to your main image on your pic (Not the background).

Dont forget to re-change the image mode back to Palette (8 Bit). Otherwise you wont see the masked area option is enable to choose when you save it as Gif. Click on Menu Bar: Edit > Mode and choose Palette (8 bit).

The Final step is just save it or export it as gif.
When the GIF Export widows appears you can choose Image color in Transparancy option. If you do it right the color you want must be there to be picked...

Sorry, in the 2nd Paragraph, i mentioned toolbar instead of Menu Bar. the right one is Menu Bar.

Heddy