從script_fu中學習影像處理技巧：製作迷彩圖案

 

 

scripts目錄下有超過100個 *.scm檔，這些是學習影像處理技巧的最好教材，以下我們來研究Chris Gutteridge 所寫的camo.scm程式。

Camouflage有偽裝、掩飾、偽裝物、掩飾手段、保護色的意思。有些昆蟲運用身上與環境相近的保護色來偽裝自己免於天敵的殺害。在陸軍裏，深綠色的迷彩圖案出現於很多地方，迷彩服、迷彩帽，戰車、軍卡、營房外的牆壁、彈藥庫外的牆壁，當過兵的人都知道這種圖案與顏色無所不在。

        讀完本文你會讚嘆作者的巧思，使用幾個濾鏡就可以無中生有創造出我的熟悉的圖案。

 

一、執行Script-Fu：

 

 

l          執行[GIMP] -> Xtns -> Script_Fu -> Patterns -> Land使用預設的參數，產生左上圖迷彩圖案。

l          迷彩圖案的效果是由三個圖層重疊顯示而產生的。

 

二、使用Gimp圖形界面，一步一步作

每個步驟所產生的影像視窗與圖層對話盒

以圖形使用者介面製作迷彩圖案，需要的步驟：

對應到camo.scm程式碼中的函數

 

 

l          File-> New，新增一個透明底色256x256影像。

l          再新增兩個透明圖層。

l          三個圖層更名為Camo Thick Layer、Camo Thick Layer、Background。

6: (set! theImage (car(gimp-image-new theWidth theHeight RGB)))

8: (set! baseLayer (car (gimp-layer-new theImage theWidth theHeight RGBA_IMAGE "Background" 100 NORMAL)))

9: (gimp-image-add-layer theImage baseLayer 0):

11: (set! thickLayer (car (gimp-layer-new theImage theWidth theHeight RGBA_IMAGE "Camo Thick Layer" 100 NORMAL)))

12: (gimp-image-add-layer theImage thickLayer 0)

14: (set! thinLayer (car (gimp-layer-new theImage theWidth theHeight RGBA_IMAGE "Camo Thin Layer" 100 NORMAL)))

15: (gimp-image-add-layer theImage thinLayer 0)

 

 

l          將Background圖層全選使用顏料桶工具塗上RGB植為(33,100,58)的綠色。

17: (gimp-selection-all theImage)

18:(gimp-palette-set-background inColor1)

19:(gimp-drawable-fill baseLayer BG-IMAGE-FILL)

 

 

l          對Camo Thick Layer與Camo Thick Layer圖層分別執行[image] -> Filters -> Render -> Clouds -> Solid-Noise，點選Tileable選項，Turbulent選項不點選，產生灰階霧狀效果。

l          點選Tileable選項，產生的圖案是無接縫的圖案。

21: (plug-in-solid-noise TRUE theImage thickLayer 1 0 (rand 65536) 1 inGrain inGrain)

22: (plug-in-solid-noise TRUE theImage thinLayer 1 0 (rand 65536) 1 inGrain inGrain)

l          對Camo Thick Layer圖層執行[image] -> Image ->Colors -> Threshold，Threshold Range設127到255。

l          對Camo Thin Layer圖層執行[image] -> Image ->Colors -> Threshold，Threshold Range設145到255。

l          利用Threshold可產生黑白二色斑點的影像，調整Threshold Range可產生不同的黑白斑點分布情況。

23:(gimp-threshold thickLayer 127 255)

24:(gimp-threshold thinLayer 145 255)

 

l          對Camo Thick Layer圖層執行[image] ->Select -> By Color將黑色的部分選住。將選取的部分

l          對Camo Thick Layer圖層執行[image] -> Edit -> Clear，將選取的部分清除。

l          執行[image] ->Select -> Invert，將選取區域反轉。

28: (gimp-palette-set-background inColor2)

29: (gimp-by-color-select thickLayer '(0 0 0) 127 REPLACE  TRUE FALSE 0 FALSE)

30: (gimp-edit-clear thickLayer)

31: (gimp-selection-invert theImage)

 

 

 

 

l          對Camo Thick Layer圖層，使用顏料桶工具將選取區域塗上RGB植為(170,170,0)的綠黃色。

32:(gimp-edit-fill thickLayer BG-IMAGE-FILL)

33:(gimp-selection-none theImage)

 

 

l          對Camo Thin Layer圖層執行[image] ->Select -> By Color將黑色的部分選住。將選取的部分

l          對Camo Thick Layer圖層執行[image] -> Edit -> Clear，將選取的部分清除。

l          執行[image] ->Select -> Invert，將選取區域反轉。

40: (gimp-palette-set-background inColor3)

41: (gimp-by-color-select thinLayer '(0 0 0) 127 REPLACE  TRUE FALSE 0 FALSE)

42: (gimp-edit-clear thinLayer)

43: (gimp-selection-invert theImage)

 

l          對Camo Thin Layer圖層，使用顏料桶工具將選取區域塗上RGB植為(150,115,100)的棕色。

l          執行[image] -> Select -> None釋放取區域。

44: (gimp-edit-fill thinLayer BG-IMAGE-FILL)

45: (gimp-selection-none theImage)

 

l          三個圖層重疊顯示產生迷彩圖案的效果。

 

 

三、原始程式碼：

l          程式碼camo.scm分三部份

l          註解，版權宣告。

l          (define (script-fu-camo-pattern   )) ，

l          (script-fu-register " script-fu-camo-pattern  )

 

; Chris Gutteridge (cjg@ecs.soton.ac.uk)

; At ECS Dept, University of Southampton, England.

 

; 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.

 

1:(define (script-fu-camo-pattern inSize inGrain inColor1 inColor2 inColor3 inSmooth inFlatten)

2:

3:        (set! old-bg (car (gimp-palette-get-background)))

4:        (set! theWidth inSize)

5:     (set! theHeight inSize)

6:        (set! theImage (car(gimp-image-new theWidth theHeight RGB)))

7:

8:        (set! baseLayer (car (gimp-layer-new theImage theWidth theHeight RGBA_IMAGE "Background" 100 NORMAL)))

9:        (gimp-image-add-layer theImage baseLayer 0)

10:

11:        (set! thickLayer (car (gimp-layer-new theImage theWidth theHeight RGBA_IMAGE "Camo Thick Layer" 100 NORMAL)))

12:        (gimp-image-add-layer theImage thickLayer 0)

13:

14:        (set! thinLayer (car (gimp-layer-new theImage theWidth theHeight RGBA_IMAGE "Camo Thin Layer" 100 NORMAL)))

15:        (gimp-image-add-layer theImage thinLayer 0)

16:

17:        (gimp-selection-all theImage)

18:        (gimp-palette-set-background inColor1)

19:        (gimp-drawable-fill baseLayer BG-IMAGE-FILL)

20:

21:        (plug-in-solid-noise TRUE theImage thickLayer 1 0 (rand 65536) 1 inGrain inGrain)

22:        (plug-in-solid-noise TRUE theImage thinLayer 1 0 (rand 65536) 1 inGrain inGrain)

23:        (gimp-threshold thickLayer 127 255)

24:        (gimp-threshold thinLayer 145 255)

25:

26:   (set! theBlur (- 16 inGrain))

27:

28:        (gimp-palette-set-background inColor2)

29:        (gimp-by-color-select thickLayer '(0 0 0) 127 REPLACE  TRUE FALSE 0 FALSE)

30:        (gimp-edit-clear thickLayer)

31:        (gimp-selection-invert theImage)

32:        (gimp-edit-fill thickLayer BG-IMAGE-FILL)

33:        (gimp-selection-none theImage)

34:        (if (= inSmooth TRUE)

35:       (script-fu-tile-blur theImage thickLayer theBlur TRUE TRUE FALSE)

36:            ()

37:        )

38:

39:

40:        (gimp-palette-set-background inColor3)

41:        (gimp-by-color-select thinLayer '(0 0 0) 127 REPLACE  TRUE FALSE 0 FALSE)

42:        (gimp-edit-clear thinLayer)

43:        (gimp-selection-invert theImage)

44:        (gimp-edit-fill thinLayer BG-IMAGE-FILL)

45:        (gimp-selection-none theImage)

46:        (if (= inSmooth TRUE)

47:       (script-fu-tile-blur theImage thinLayer (/ theBlur 2) TRUE TRUE FALSE)

48:            ()

49:        )

50:

51:

52:        (if (= inFlatten TRUE)

53:            (gimp-image-flatten theImage)

54:            ()

55:        )

56:        (gimp-palette-set-background old-bg)

57:        (gimp-display-new theImage)

58:   )

 

; Register the function with the GIMP:

 

(script-fu-register

 "script-fu-camo-pattern"

 _"<Toolbox>/Xtns/Script-Fu/Patterns/Camouflage..."

 "Camouflage pattern"

 "Chris Gutteridge: cjg@ecs.soton.ac.uk"

 "28th April 1998"

 "Chris Gutteridge / ECS @ University of Southampton, England"

 ""

 SF-ADJUSTMENT _"Image Size"    '(256 10 1000 1 10 0 1)

 SF-ADJUSTMENT _"Granularity"   '(7 0 15 1 1 0 0)

 SF-COLOR      _"Color 1"       '(33 100 58)

 SF-COLOR      _"Color 2"       '(170 170 60)

 SF-COLOR      _"Color 3"       '(150 115 100)

 SF-TOGGLE     _"Smooth"        FALSE

 SF-TOGGLE     _"Flatten Image" TRUE

)

 

 

四、其他函數的說明：