Resize all images in folder an descendants

resizeall.py

#!/usr/bin/python

import sys, os, logging, math, ConfigParser, random,inspect
import Image, ImageStat


frameSize = (720,480)
frameRatio = float(frameSize[0])/float(frameSize[1])

def files(folder):
    for path, folders, files in os.walk(folder):
        for name in files:
            yield os.path.join(path, name)


def buildTile(image):
    width=frameSize[0]
    height=frameSize[1]
    size=frameSize
    imageRatio = float(image.size[0])/float(image.size[1])
    if frameRatio==imageRatio:
        newSize=size
    elif frameRatio < imageRatio:
        newSize=(int(imageRatio*height),int(height))
    else:
        newSize=(int(width),int(width/imageRatio))
    tile = image.resize(newSize,Image.ANTIALIAS)

    l = int(newSize[0]-size[0])/2
    u = int(newSize[1]-size[1])/2

    box=(l,u,l+size[0],u+size[1])
    if box != (0,0,size[0],size[1]):
        tile = tile.crop(box)

    return tile

folder = sys.argv[1]
for file in files(folder):
    try:
        image = Image.open(file)
        if image.size!=frameSize:
            tile = buildTile(image)
            tile.save(file,quality=95)
            print "resized",file
        else:
            print "already resized",file
    except Exception,e:
        print file, e