This tutorial applies to both Digital Image Pro versions 9
and 10.
When you scan an object, or want to use a jpg file from the
internet, it usually has a white or solid background surrounding an isolated
image. This tutorial explains how to extract the image, and create a cutout with
a transparent surround in Digital Image Pro v9 or v10.
When placed on a colored background (black used here), the
white surround is visible.
To delete the white background select the Magic Wand tool
from the Selection dock.
On the floating tool palette that appears, select Smooth
edges.
In this instance, since there is no white in the image we
are keeping we can have Contiguous deselected. If there was white in the image
you would want to select Contiguous – this limits the selection of the color to
connected areas and would prevent the removal of the same color in the image,
Set the tolerance to 0 and the Selection Mode to new.
Now click any where on the white surrounding the butterfly
with the magic wand.
The white area is outlined by “marching ants” – moving
dashed lines.
Move to Edit on the toolbar and select Delete.
The white is removed from the background leaving behind the
image.
If the white has been successfully removed, click on the
Object tool and then anywhere on the canvas to apply the change to your image.
Often however, a halo of the background color removed
remains on the image. As visible here on this image there is a thin band of
white outlining the cutout.
To remove a similar halo at this stage:
Zoom in as close as possible to show the pixellation
without being too distorted. I have zoomed to 365%
Select the Magic Wand tool from the Selection dock.
On the floating tool palette that appears, select Smooth
edges.
For this step have Contiguous deselected.
Ensure the Selection Mode is set to +
To select the white band we need to increase the tolerance.
The tolerance number determines what shades of the color is included in the
selection. As you increase the tolerance it chooses more pixels that contain
lighter or darker parts of the color. This process is a bit hit and miss, start
with a low number- I have begun with a tolerance level of 20, knowing this will
include some of the grey at the edges of the white outline.
Click on part of the white halo and the marching ants will
show the areas selected.
Move to Edit on the toolbar and select Delete.
There are still areas of halo left so repeat the same step.
As you have the + mode selection you can select another area.
I repeated this process twice more to get the result I was
after. You can see in this magnification that the fringing has been removed.
Select The Object tool and click anywhere on the canvas to
complete.
Here is my final cut out shown with both a black and blue
background.
Things to note:
Increase the tolerance in the first step and use the Add +
selection mode before completing your selection if you notice a halo.
You could select to feather the edges to reduce the halo.
Try a feather amount of around 3 to start with.
You can also use the Effects> Transparency> Transparency
Brush with the opacity level set to 100% to clean up stray edges.
To remove areas inside an image where the background may
show in gaps, use the Add + Selection Mode.
