Files
AutoFileName/getimageinfo.py
2013-11-25 23:45:28 -05:00

63 lines
1.8 KiB
Python

# 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.BytesIO(data)
jpeg.read(2)
b = jpeg.read(1)
try:
while (b != b''):
while (b != b'\xFF'): b = jpeg.read(1)
while (b == b'\xFF'): b = jpeg.read(1)
if (b >= b'\xC0' and b <= b'\xC3'):
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