画像ファイルのモノクロ化

Code:
{def original-pm =  {Pixmap.from-url {url "http://www.fuji-kawaguchiko.com/images/p/008event/koyo/main.jpg"}}}



{def fr = {Frame}}



{CommandButton

    label = "保存",

    {on Action do



        def pm = {original-pm.clone}



        ||単純平均法でグレースケール変換

        {for x:int = 0 below pm.max-x  do

            {for y:int = 0 below pm.max-y do

                def px = {pm.get x, y} asa Pixel 

                def new-y = (px.red + px.blue + px.green) / 3



                ||加重平均法

                ||def new-y = 0.298912 * px.red + 0.586611 * px.green  + 0.114478 * px.blue

                def new-px = {Pixel.create new-y, new-y, new-y}

                {pm.set x,y, new-px}

            }

        }

        ||保存（jpegのみ）

        {if-non-null u = {choose-file style = FileDialogStyle.save-as} then

            def id = {ImageData}

            set id.pixmaps = {{Array-of Pixmap} pm}

            {id.save-to-url u, "image/jpeg"}

            def ig = {ImageGraphic u}

            {fr.add ig, replace? = true}

        }

    }

}

{value fr}