property NSUUID : a reference to current application’s NSUUID
property NSString : a reference to current application’s NSString
property NSImage : a reference to current application’s NSImage
property NSColorSpace : a reference to current application’s NSColorSpace
property NSPNGFileType : a reference to current application’s NSPNGFileType
property NSBitmapImageRep : a reference to current application’s NSBitmapImageRep
property NSColorRenderingIntentPerceptual : a reference to current application’s NSColorRenderingIntentPerceptual

set aFile to POSIX path of (choose file of type {"public.image"} with prompt "Select Image A")
set aImage to NSImage’s alloc()’s initWithContentsOfFile:aFile

set fRes to retUUIDfilePath(aFile, "png") of me
set sRes to saveNSImageAtPathAsGreyPNG(aImage, fRes) of me

–指定ファイルパスを元にUUIDのファイル名、指定拡張子をつけたファイルパスを作成して返す
on retUUIDfilePath(aPath, aEXT)
　　set aUUIDstr to (NSUUID’s UUID()’s UUIDString()) as string
　　set aPath to ((NSString’s stringWithString:aPath)’s stringByDeletingLastPathComponent()’s stringByAppendingPathComponent:aUUIDstr)’s stringByAppendingPathExtension:aEXT
　　return aPath
end retUUIDfilePath

–NSImageを指定パスにPNG形式で保存
on saveNSImageAtPathAsGreyPNG(anImage, outPath)
　　set imageRep to anImage’s TIFFRepresentation()
　　set aRawimg to NSBitmapImageRep’s imageRepWithData:imageRep
　　
　　–ビットマップをグレースケール変換
　　set bRawimg to convBitMapToDeviceGrey(aRawimg) of me
　　
　　set pathString to NSString’s stringWithString:outPath
　　set newPath to pathString’s stringByExpandingTildeInPath()
　　
　　set myNewImageData to (bRawimg’s representationUsingType:(NSPNGFileType) |properties|:(missing value))
　　set aRes to (myNewImageData’s writeToFile:newPath atomically:true) as boolean
　　return aRes –true/false
end saveNSImageAtPathAsGreyPNG

–NSBitmapImageRepをグレースケールに変換する
on convBitMapToDeviceGrey(aBitmap)
　　set aSpace to NSColorSpace’s deviceGrayColorSpace()
　　set bRawimg to aBitmap’s bitmapImageRepByConvertingToColorSpace:aSpace renderingIntent:(NSColorRenderingIntentPerceptual)
　　return bRawimg
end convBitMapToDeviceGrey

property NSUUID : a reference to current application’s NSUUID
property NSString : a reference to current application’s NSString
property NSImage : a reference to current application’s NSImage
property NSColorSpace : a reference to current application’s NSColorSpace
property NSBitmapImageRep : a reference to current application’s NSBitmapImageRep
property NSColorRenderingIntentDefault : a reference to current application’s NSColorRenderingIntentDefault

set aFile to POSIX path of (choose file of type {"public.image"} with prompt "Select Image")
set aImage to NSImage’s alloc()’s initWithContentsOfFile:aFile

set nsImageRes to convNSImageAsGrey(aImage) of me

–NSImageをグレースケールに変換する（NSImageで入出力）
on convNSImageAsGrey(anImage)
　　set imageRep to anImage’s TIFFRepresentation()
　　set aRawimg to NSBitmapImageRep’s imageRepWithData:imageRep
　　set aSpace to NSColorSpace’s deviceGrayColorSpace()
　　set bRawimg to aRawimg’s bitmapImageRepByConvertingToColorSpace:aSpace renderingIntent:(NSColorRenderingIntentDefault)
　　set outImage to NSImage’s alloc()’s initWithSize:(bRawimg’s |size|())
　　outImage’s addRepresentation:(bRawimg)
　　return outImage
end convNSImageAsGrey