This action does NOT rescale the image, it only crops it or expands it with empty pixels with the background colour. Use the scale action for that purpose. If you want to add a border of a certain size, use the border action.
The new width of the image.
The new height of the image.
Dots per inch. The value <dpi> keeps the default resolution of the photo.
Describes the horizontal alignment by percentage: from 0% (left), 50% (middle) to 100% (right).
Describes the vertical alignment by percentage: from 0% (top), 50% (middle) to 100% (bottom).
The background colour in case the image expands.
The opacity of the resulting image.