Here is a Pin-Stripe border script (Oregonian's tutorial)

It works on the current layer so it is a little more versatile. The width and colors can be specified. Tested on RGB and gray-scale images.

Appears at Filters > Decor > Pin-Stripe Border...

Edit1: Updated the script to fix frame shift problem.
Edit2: Set paint tool and add option to merge border down or not.

Drat!!!
I just noticed that the border is lopsided by one pixel because of the way GIMP strokes a selection from a script.

I'll have it updated in a few minutes... I hope.

Fixed!!!
Updated the script in the original post.

Slick! Thank you!

A suggestion. If you'd preface your filenames with bkh, we'd know who did them in the file list.
bkh-pin-stripe-border.scm

Done with the default settings.

Would it be possible to make a choice in the script dialog to leave the border on a separate layer for later editing if desired?

bkh, nice job on the pin-stripe script. I'd suggest, however, that you use 'gimp-context-set-paint-method' so that your script is ensured to paint with the pencil or paintbrush, regardless the active paint tool. As currently written, depending upon what paint tool is active when the script is executed, the result might not be as expected.

Since the PDB browser does not list the available methods, I will post them here: "gimp-pencil", "gimp-paintbrush", "gimp-eraser", "gimp-airbrush", "gimp-ink", "gimp-clone", "gimp-heal", "gimp-perspective-clone", "gimp-convolve", "gimp-smudge", and "gimp-dodge-burn". The values are indeed strings, so the quotation marks should be included in the procedure call. For example,

The pencil would be the best one. No antialiasing. Everything is horizontal or vertical so it's not needed.

Nice script!
Thanks for sharing it bkh.

saulgoode, thanks for the compliment and information.
As you probably noticed, I had already run into trouble with the paint mode and opacity. I was wondering what the paint method did. I've added it to the script.


Done.


Looking at your tutorial, the final stroke is 5px, which gives a 2.5px wide line inside the frame. That feathers the outer line into the inner line, which gives a quasi bevel effect. The paint brush will do the same feathering, the pencil won't. The script uses a 100% hard brush so it produces exactly the same type of stroke as the line stroke does. I'll leave it that way for now.

Thanks for the feedback everyone.

Modified script is in the original post.

Nicely done!