Fix script for Python 3

Fix script for Python 3

AutoFileName is an extension for Sublime Text 2. But when Sublime Text
switch from Python 2 to Python 3, expansion ceased to operate
normally(does not work with jpg). If anyone knows how to fix the script,
please make pull request here.
# from io import BytesIO
import io
import struct
def getImageInfo(data):
olddata = str(data)
data = bytes(data)
size = len(data)
height = -1
width = -1
content_type = ''
# handle GIFs
if (size >= 10) and data[:6] == b'GIF89a':
# Check to see if content_type is correct
content_type = 'image/gif'
w, h = struct.unpack("<HH", data[6:10])
width = int(w)
height = int(h)
# See PNG 2. Edition spec (http://www.w3.org/TR/PNG/)
# Bytes 0-7 are below, 4-byte chunk length, then 'IHDR'
# and finally the 4-byte width, height
elif ((size >= 24) and data[:8] == b'\211PNG\r\n\032\n'
and (data[12:16] == b'IHDR')):
w, h = struct.unpack(">LL", data[16:24])
width = int(w)
height = int(h)
# Maybe this is for an older PNG version.
elif (size >= 16) and data[:8] == b'\211PNG\r\n\032\n':
# Check to see if we have the right content type
w, h = struct.unpack(">LL", data[8:16])
width = int(w)
height = int(h)
# handle JPEGs
# elif (size >= 2) and data[:2] == b'\377\330':
# jpeg = io.StringIO(olddata)
# print(bytes(ord(jpeg.read(1))))
# jpeg.read(2)
# b = jpeg.read(1)
# try:
# while (b and ord(b) != 0xDA):
# while (ord(b) != 0xFF): b = jpeg.read(1)
# while (ord(b) == 0xFF): b = jpeg.read(1)
# if (ord(b) >= 0xC0 and ord(b) <= 0xC3):
# jpeg.read(3)
# h, w = struct.unpack(">HH", jpeg.read(4))
# break
# else:
# jpeg.read(int(struct.unpack(">H", jpeg.read(2))[0])-2)
# b = jpeg.read(1)
# width = int(w)
# height = int(h)
# except struct.error:
# pass
# except ValueError:
# pass
return width, height
Link to the file.