GIMP選択範囲の周辺色で塗りつぶすPython-Fuプラグイン

#!/usr/bin/env python
# coding: utf8

from gimpfu import *
from array import array
from time import time

def plugin_main(image, layer):

    start1 = time()

    # レイヤーの幅と高さを取得
    w = layer.width
    h = layer.height
    
    # 範囲選択を取得
    (non_empty,x1,y1,x2,y2) = pdb.gimp_selection_bounds(image)
    
    # 範囲選択されていない場合終了
    if (non_empty == 0):
        gimp.message("Not Select")
        return
    # 色を取得
    cx = -1
    cy = -1
    if (x1 > 0 and y1 > 0):
        cx = x1 - 1
        cy = y1 - 1
    elif (x2 < (w-1) and y1 > 0):
        cx = x2 + 1
        cy = y1 - 1
    elif (x2 < (w-1) and y2 < (h-1)):
        cx = x2 + 1
        cy = y2 + 1
    elif (x1 > 0 and y2 < (h-1)):
        cx = x1 - 1
        cy = y2 + 1
    else:
        gimp.message("x1:{0} x2:{1} y1:{2} y2:{3}".format(x1, x2, y1, y2))        
        return
    
    
    # ピクセルの色を取得
    _, pix = pdb.gimp_drawable_get_pixel(layer, cx, cy)
    color = (pix[0], pix[1], pix[2], 1.0)
    
    gimp.message("r:{0} g:{1} b:{2}".format(pix[0], pix[1], pix[2]))

    # 前景色にセット    
    pdb.gimp_context_set_foreground(color)
    
    # 前景色で塗りつぶし
    pdb.gimp_drawable_edit_fill(layer, 0)
    
    # レイヤーの更新
    layer.flush()
    #layer.merge_shadow()
    layer.update(0,0,w,h)

    proc_time = time() - start1
    gimp.message("実行時間:{0}".format(proc_time))
    

register("AutoColorFill", "", "", "", "", "",
    "自動塗りつぶし", 
    "RGB*",
    [
    (PF_IMAGE, "image", "Input image", None),
    (PF_DRAWABLE, "drawable", "Drawable", None)
    ],
    [],
    plugin_main,
    menu = "<Image>/Filters")

main()