opentbs, pictures and adjust

i have an LO template, where i want to insert some pictures (i know, i have to use replace)  Now i don't know on advance which resolution these have. So i Thought to use this adjust parameter.
But it seems that the picture is adjusted in both directions (width and height) to match the templates pictures sizes. i naturally want to keep the original picture ratio. How can i archive this ?
in my LO template
[c.one;ope=changepic;adjust]

Hi Jef,

Parameter "adjust" do keep the original ratio. But they are several ways to achieve this.
"adjust" (without value) will change either the height the width in order to keep the picture into the template picture box.

ok, works now. I suppose there is no easy way to remove an image that has not been replaced (magnet tag?). I also get the message 'Read error' in picture that has not been replaced, although i specified a default picture.

template:
[pict.2;ope=changepic;adjust=samewidth;default=current;noerr]

greetz