[Courses][gimp] Lesson 7: Selecting Complex Shapes

[Julie Sloan]

On Friday 11 March 2005 10:50 pm, Akkana Peck wrote:
> In Lesson 4, we used some simple basic tools to select part of an
> image.  In this lesson, I'll cover selection of complex shapes.

> GENERAL ADVICE
>
> When selecting images out of an image, there are two important tricks:
> (1) Zoom the image as much as you can, so you can see what you're
> doing, and (2) Turn on "feathering".

Zoom is my friend.  In gimp1.2.5 I use the [+  -  1] keys and do not need 
CTRL with them.  I also think [view > new view] is indispensable when 
editing a zoomed image.

> That's where Bezier Paths come in!  The Bezier (pronounced
> "bez-ee-ay") 

I think of it as "BEE zjer."   I will try to fix this mindset   :)

> Time to start!  Click-and-release the mouse button wherever you want
> to start your selection.

I began with a sunflower:
http://juliesloan.home.mindspring.com/gimp/sunflower.jpg

Here is a screenshot of my initial selection:
http://juliesloan.home.mindspring.com/gimp/snapshot1.jpg

> What if you click in the wrong place?

> In gimp 1, ctrl-click seems to move the current point.

This takes some practice.  
As does making additional paths after the first one; It took me a while to 
figure out had to click "new path" in the paths dialogue BEFORE I start 
selecting.

> Gimp 1.2 has a Feathering checkbox in the Bezier Selection Tool
> Options dialog, like most selection tools.  

FWIW  I turned on feathering in Bezier select, but when I closed the gimp 
and reopened it, it had reverted to the non-feathering default.

> You've made your selection.  What can you do with it?
>
> Of course, you can copy, then paste into another image

I did that:
http://juliesloan.home.mindspring.com/gimp/onwhite.jpg

but then I noticed I needed to take more background out, among the leaves :(  
so I did:
http://juliesloan.home.mindspring.com/gimp/onwhite2.jpg

but this doesn't help if I want to blur or otherwise enhance (dehance?) the 
background, so I went back to my xcf and made more BEEzjer - I mean 
bez-ee-YAY selections
and once I decided how I was going to change the bg made a note of the 
values and applied them to each selection, one at a time:

using colors > curves to lighten and darken, and gaussian blur RLE:

http://juliesloan.home.mindspring.com/gimp/sunflower-light.jpg
http://juliesloan.home.mindspring.com/gimp/sunflower-dark.jpg
http://juliesloan.home.mindspring.com/gimp/sunflower-blur.jpg

[filters >noise > hurl] makes an interesting effect too  :)

I ended up with a favorite, /weird.jpg, which would have looked better with 
a fine edge selected instead of feathered, but still think it's cool.

Julie


> Homework: Select a complex shape from an image, using path or
> intelligent scissors, and apply any gimp filter (or combination of
> filters) to either the shape or its background.  Or, if you prefer,
> just paste the shape into another image.
>
> Next lesson: How to get really cool looking text.
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