import io
import os
import picamera
import time
from datetime import datetime
from PIL import Image

camera = picamera.PiCamera()

difference = 20
pixels = 100

width = 1280
height = 960

def compare():
	camera.resolution = (100, 75)
	stream = io.BytesIO()
	camera.capture(stream, format = 'bmp')
	stream.seek(0)
	im = Image.open(stream)
	buffer = im.load()
	stream.close()
	return im, buffer
def newimage(width, height):
	time = datetime.now()
	filename = 'motion-%04d%02d%02d-%02d%02d%02d.jpg' % (time.year, time.month,time.day, time.hour,time.minute, time.second)
	camera.resolution = (width, height)
	camera.capture(filename)
	print 'Captured %s' % filename
image1, buffer1 = compare()

timestamp = time.time()

while (True):
	image2, buffer2 = compare()

	changedpixels = 0
	for x in xrange(0, 100):
		for y in xrange(0, 75):
			pixdiff = abs(buffer1[x,y][1]- buffer2[x,y][1])
			if pixdiff > difference:		
				changedpixels += 1
	if changedpixels > pixels:
		timestamp = time.time()
		newimage(width, height)
	image1 = image2
	buffer1 = buffer2