Saving a transparent PNG & GIF from EMF or BitBlt

This any help?

http://www.vbaccelerator.com/home/Vb/Code/vbMedia/Using_GDI_Plus/Reading_and_Writing_JPG__PNG__TIF_and_GIF_Files/article.asp

saving as a gif
  http://www.xtremevbtalk.com/t92821.html

also
 http://pagesperso-orange.fr/pierre.g/xnview/engfl.html (XN View)

Thanks a lot.
But actually I need to make a transparent file from an opaque bitmap. The process is:
- open a bitmap
- replace pixels from some rgb color to make a transparency
- save it as GIF or PNG

Other option is to make the GIF/PNG from EMF that is allready a transparent metafile.

I need to test the GFL SDK, may this will work...

so you need to apply a mask based on a given RGB value?

I have found this, but not checked it:
http://www.planet-source-code.com/vb/scripts/ShowCode.asp?txtCodeId=49560&lngWId=1

As I see, it could be a solution. But my vb crashes when i run the sample.
By the way, there is class called cPallete, but i dont know how to use it...

I expect its for 256 colour (color) bitmaps.  They have a table to list the true RGB value for each pixel byte.  (I wrote my own bmp class beffore, but it couldnt deal with transparency or non BMPs).

I will take a look at the project from home later and see what I can do with it.

found a bug, have fixed.

Will post fix, instuctions and sample code shortly.

Is the gif for use within a VB application, or for on the web?

Wow man!
The GIF is for multipropose uses. I am making an application that can exports images in many formats.

By the way, I can open the GIF in Photoshop but can not display it in IE7.

Do you know why?

no thats why I asked "Is the gif for use within a VB application, or for on the web?"

It not just for you, but I cannot see why.  It also works in FrontPage which is bizzare but it works in firefox also.  I an only imagine its some oddity in the standard.

Is this good enough?  If it were for use with IE I would have to search for a new answer as I cannot see why this code doesnt work for IE.

If the GIF can not be viewed in IE this algoritm will not 100% useful.
Using another library (as freeimage.dll) to re-save maybe this will work.

Off course I wll accept your solution anyway. Thanks a lot.

By the way, do you know how can i export an EMF into transparent GIF and PNG?

thanks for that!its put me at #12 for this year so far ;)

I don't but if I find anything on the subject, I'll post it as a comment