image changing size

[lossygimp]

I start with an image 8192x8192, add layer, select all, color to alpha, then apply filter cold metal, and my image immediately balloons to 9430x15165. What is happening?

[rich2005]

(04-06-2021, 05:00 PM)lossygimp Wrote: I start with an image 8192x8192, add layer, select all, color to alpha, then apply filter cold metal, and my image immediately balloons to 9430x15165. What is happening?

Where did you get the filter cold metal ?  There is an old Gimp 2.8 script 'Cool Metal' is it that one ?

[lossygimp]

(04-06-2021, 05:19 PM)rich2005 Wrote:

(04-06-2021, 05:00 PM)lossygimp Wrote: I start with an image 8192x8192, add layer, select all, color to alpha, then apply filter cold metal, and my image immediately balloons to 9430x15165. What is happening?

Where did you get the filter cold metal ?  There is an old Gimp 2.8 script 'Cool Metal' is it that one ?

Yes. Why would it change the canvas size?

[rich2005]

(04-06-2021, 06:01 PM)lossygimp Wrote: .....Why would it change the canvas size?

That is the way the script works.
You selected-all which selects all of the canvas, not just an individual layer, and the script uses that to add (1) a dropshadow of sorts, and (2) a reflection of the layer by increasing the canvas size. This will destroy your image. The script is really meant for making smallish banners. You can get a better idea if you use the other menu entry File -> Create -> Logos -> Cool Metal which has text entry.

If you want to keep your background image You might do it this way
Duplicate the image Image -> Duplicate
Do not use select, Crop the layer: Crop tool with current layer only enabled in the tool options. Close to the shape in question.
Apply alpha to selection to remove the background (you say white in your project)
Apply the Cool Metal script Filters -> Alpha to Logo -> Cool Metal
That gives several layers. Turn the background off and flatten the image.
If you want that back in the original, move (copy / paste or click-n-drag) and adjust for position.

I can just about get that in a 1 minute animation: https://i.imgur.com/rQY1XiB.mp4

[lossygimp]

(04-06-2021, 06:34 PM)rich2005 Wrote: That is the way the script works.
You selected-all which selects all of the canvas, not just an individual layer, and the script uses that to add (1) a dropshadow of sorts, and (2) a reflection of the layer by increasing the canvas size. This will destroy your image. The script is really meant for making smallish banners.  You can get a better idea if you use the other menu entry File -> Create -> Logos -> Cool Metal which has text entry.

If you want to keep your background image You might do it this way
Duplicate the image Image -> Duplicate
Do not use select, Crop the layer: Crop tool with current layer only enabled in the tool options. Close to the shape in question.
Apply alpha to selection to remove the background (you say white in your project)
Apply the Cool Metal script Filters -> Alpha to Logo -> Cool Metal
That gives several layers. Turn the background off and flatten the image.
If you want that back in the original, move (copy / paste or click-n-drag) and adjust for position.

I can just about get that in a 1 minute animation: https://i.imgur.com/rQY1XiB.mp4

Thank you!