[Ipe-discuss] transparent images/gif

[Otfried Cheong]

On Tue, Oct 20, 2015, at 03:36, Wolfram Jahn wrote:
> in older versions of ipe you could insert gif images, which doesn't seem
> to be possible anymore (only pngs and jpgs appear as valid images).
> 
> The problem is that I used to convert png with transparent background to
> gifs, which ipe could then successfully integrate (with transparency).
> 
> Is this feature of ipe effectively lost? Or am I just not seeing
> something?

Ipe has the ability to set a color key for a bitmap to enable (a simple
kind of) transparency (http://ipe.otfried.org/manual/manual_41.html) -
but currently the PNG reading code does not seem to set this from the
PNG image.

I think this may have gotten lost in the transition from Ipe 6 to Ipe 7.
  In any case, I've opened an issue to fix this, but don't expect that
before next year.

In the mean time, you should be able to get a transparent image by
editing the Ipe XML file by hand and inserting the ColorKey attribute in
the bitmap. (One could also make a small ipelet to do this...)

Cheers,
 Otfried