mirror of
https://github.com/python-pillow/Pillow.git
synced 2024-11-15 22:26:55 +03:00
103 lines
2.0 KiB
Python
103 lines
2.0 KiB
Python
#
|
|
# The Python Imaging Library.
|
|
# $Id$
|
|
#
|
|
# Binary input/output support routines.
|
|
#
|
|
# Copyright (c) 1997-2003 by Secret Labs AB
|
|
# Copyright (c) 1995-2003 by Fredrik Lundh
|
|
# Copyright (c) 2012 by Brian Crowell
|
|
#
|
|
# See the README file for information on usage and redistribution.
|
|
#
|
|
|
|
|
|
"""Binary input/output support routines."""
|
|
|
|
|
|
from struct import pack, unpack_from
|
|
|
|
|
|
def i8(c):
|
|
return c if c.__class__ is int else c[0]
|
|
|
|
|
|
def o8(i):
|
|
return bytes((i & 255,))
|
|
|
|
|
|
# Input, le = little endian, be = big endian
|
|
def i16le(c, o=0):
|
|
"""
|
|
Converts a 2-bytes (16 bits) string to an unsigned integer.
|
|
|
|
:param c: string containing bytes to convert
|
|
:param o: offset of bytes to convert in string
|
|
"""
|
|
return unpack_from("<H", c, o)[0]
|
|
|
|
|
|
def si16le(c, o=0):
|
|
"""
|
|
Converts a 2-bytes (16 bits) string to a signed integer.
|
|
|
|
:param c: string containing bytes to convert
|
|
:param o: offset of bytes to convert in string
|
|
"""
|
|
return unpack_from("<h", c, o)[0]
|
|
|
|
|
|
def si16be(c, o=0):
|
|
"""
|
|
Converts a 2-bytes (16 bits) string to a signed integer, big endian.
|
|
|
|
:param c: string containing bytes to convert
|
|
:param o: offset of bytes to convert in string
|
|
"""
|
|
return unpack_from(">h", c, o)[0]
|
|
|
|
|
|
def i32le(c, o=0):
|
|
"""
|
|
Converts a 4-bytes (32 bits) string to an unsigned integer.
|
|
|
|
:param c: string containing bytes to convert
|
|
:param o: offset of bytes to convert in string
|
|
"""
|
|
return unpack_from("<I", c, o)[0]
|
|
|
|
|
|
def si32le(c, o=0):
|
|
"""
|
|
Converts a 4-bytes (32 bits) string to a signed integer.
|
|
|
|
:param c: string containing bytes to convert
|
|
:param o: offset of bytes to convert in string
|
|
"""
|
|
return unpack_from("<i", c, o)[0]
|
|
|
|
|
|
def i16be(c, o=0):
|
|
return unpack_from(">H", c, o)[0]
|
|
|
|
|
|
def i32be(c, o=0):
|
|
return unpack_from(">I", c, o)[0]
|
|
|
|
|
|
# Output, le = little endian, be = big endian
|
|
def o16le(i):
|
|
return pack("<H", i)
|
|
|
|
|
|
def o32le(i):
|
|
return pack("<I", i)
|
|
|
|
|
|
def o16be(i):
|
|
return pack(">H", i)
|
|
|
|
|
|
def o32be(i):
|
|
return pack(">I", i)
|