Hi gimp-people,

Gimp version: 1.2.1, OS: Irix 6.5.15 on an SGI O2.

I'm trying to use plug-in-colortoalpha in non-interactive mode from a script, in order to look "through" the black part of an image into the layer below. Unfortunately, non-interactive mode does not work for this plugin. It always returns an "invalid parameters" error.

Looking at the code (downloaded from http://registry.gimp.org/file/colortoalpha.c?action=view&id=257) I can see the problem. On line 192, within the (runmode == RUN_NONINTERACTIVE) case, it checks that the number of parameters == 5, the fifth one being a threshold. If this parameter isn't passed, it returns STATUS_CALLING_ERROR. However, this plugin is only registered with the gimp to expect four parameters, and so a fifth parameter is never passed (even if it is specified in the script).

The fix is pretty obvious. Either set this parameter to a default (rather than returning an error) or register the plugin with five parameters. The first solution is probably easier and would be compatible with any current scripts that use plug-in-colortoalpha.

However, my system is not setup with all the gimp headers and libraries to compile this, and I also don't have access to CVS to check the file out and in. I was therefore wondering if there is some kindly soul out there who wouldn't mind making this change and compiling it on Irix 6.5 for me, and sending the executable. I will even provide the corrected source code if need be, although it won't have been checked out of CVS.

Pretty pretty please?

Thanks a lot,

Giles