; LAB-sharpen.scm
; 0.2 (2004-08-17)
; 0.1 (2004-08-11)
;
; This program is free software; you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation; either version 2 of the License, or
; (at your option) any later version.
;
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
; GNU General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program; if not, write to the Free Software
; Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
;
; LAB sharpen 
; based on the tutorials 
; http://www.gimpguru.org/Tutorials/ReducingCCDNoise/index.shtml
; http://www.gimpguru.org/Tutorials/SmartSharpening/index.shtml
;
; (C) 2004 by Thorsten Schnebeck (thorsten.schnebeck@gmx.net)
;
; copy this script to ~/.gimp/scripts/lab-sharpen.scm
; and in Gimp2: Xtns->Script-Fu->Refresh Scripts
; you find this script in Script-Fu/Alchemy/LAB-Sharpen...

(define (spline) 
	(let* ((a (cons-array 6 'byte))) 
	(set-pt a 0 0 0) 
	(set-pt a 1 143 106)
	(set-pt a 2 255 255) 
a)) 
 

(define (script-fu-lab-sharpen image drawable radius amount threshold denoise)
	(gimp-image-undo-group-start image)
	
	; Build edge-mask
	(set! mask (car (gimp-image-duplicate image)))
	(set! drawable (car (gimp-image-get-active-drawable mask)))
	(plug-in-edge 1 mask drawable 1.7 1 0)
	(gimp-image-convert-grayscale mask)
	(plug-in-gauss-iir2 1 mask drawable 2 2)
;	(gimp-curves-spline drawable 0 6 (spline))
	(gimp-edit-copy drawable)
	(gimp-image-delete mask)
	
	; Call a plugin to separate LAB-layers into a new image
	(set! drawable (car (gimp-image-get-active-drawable image)))
	(set! lab_image (car (plug-in-decompose 1 image drawable "LAB" 1)))
	(set! layers (gimp-image-get-layers lab_image)) 
	(set! b_layer (aref (cadr layers) 0))
	(set! a_layer (aref (cadr layers) 1))
	(set! l_layer (aref (cadr layers) 2))
	(gimp-drawable-set-visible a_layer 0)
	(gimp-drawable-set-visible b_layer 0)
	(gimp-image-set-active-layer lab_image l_layer)
	
	; Selection channel
	(set! selection (car (gimp-channel-new lab_image (car (gimp-image-width image)) (car (gimp-image-height lab_image)) "Selection" 50 '(128 128 128))))
	(gimp-image-add-channel lab_image selection 0)
	(gimp-floating-sel-anchor (car (gimp-edit-paste selection 0)))
	(gimp-selection-load selection)
	(gimp-image-remove-channel lab_image selection)
	(plug-in-unsharp-mask 1 lab_image l_layer radius amount threshold)
	(if (> denoise 0)
		(begin
			(gimp-selection-invert lab_image)
			(plug-in-gauss-iir2 1 lab_image l_layer denoise denoise)
		)
	) 
	(set! compose (car (plug-in-drawable-compose 1 lab_image l_layer a_layer b_layer drawable "LAB")))
	
	(gimp-edit-copy (car (gimp-image-get-active-drawable compose)))
	(gimp-image-delete lab_image)	
	
	; Flush the display
	(gimp-image-undo-group-end image)
	(gimp-displays-flush)
	(gimp-display-new compose)
;	(gimp-display-new lab_image)
)

(script-fu-register "script-fu-lab-sharpen" 
"<Image>/Script-Fu/Alchemy/LAB-Sharpen..."

"LAB sharpen
The better way to sharpen/denoise your digital images.
http://www.gimpguru.org/Tutorials/SmartSharpening/index.shtml"

"Thorsten Schnebeck"
"Thorsten Schnebeck (thorsten.schnebeck@gmx.net)"
"2004"
"RGB*"
	SF-IMAGE		"Image"			0
	SF-DRAWABLE		"Drawable"		0
	SF-ADJUSTMENT	_"Radius"		'(1.5 1 50 0.5 1 1 1)
	SF-ADJUSTMENT	_"Amount"		'(0.6 0 5 0.1 0.5 1 1)
	SF-ADJUSTMENT	_"Threshold"	'(2 0 5 0.5 1 1 1)
	SF-ADJUSTMENT	_"Denoise"		'(0 0 100 1 10 0 1)
)
;Tab=4