自炊ヘルパーその1: JPEGファイルを縦横半分にリサイズ、指定したフォルダ以下を階層的に処理

BatchResize.groovy

import java.awt.Image
import java.awt.image.BufferedImage
import javax.imageio.ImageIO

def rootDir = new File(args[0])
rootDir.eachFileRecurse { file ->
	if(file.name ==~ /[^s].*\.jpg/) { // skip file starting with "s"
		def srcFileName = file.name
		def path = file.absoluteFile.parent
		def dstFileName = 's' + srcFileName
		println "Shrinking: ${path}\\${srcFileName}"
		resizeImage(file, "${path}/${dstFileName}")
		file.delete()
	}
}

def resizeImage(srcFile, dstPath) {
	def image = ImageIO.read(srcFile)
	def w = image.width.intdiv(2)
	def h = image.height.intdiv(2)
	def resizedImage = new BufferedImage(w, h, image.type)
	resizedImage.getGraphics().drawImage(
		image.getScaledInstance(w, h, Image.SCALE_AREA_AVERAGING),
	    	0, 0, w, h, null)
	ImageIO.write(resizedImage, "jpeg", new File(dstPath))
}