openmedialibrary_platform_d.../lib/python3.7/site-packages/PIL/_binary.py

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#
# 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.
#
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from struct import unpack_from, pack
from ._util import py3
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if py3:
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def i8(c):
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return c if c.__class__ is int else c[0]
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def o8(i):
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return bytes((i & 255,))
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else:
def i8(c):
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return ord(c)
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def o8(i):
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return chr(i & 255)
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# Input, le = little endian, be = big endian
def i16le(c, o=0):
"""
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Converts a 2-bytes (16 bits) string to an unsigned integer.
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c: string containing bytes to convert
o: offset of bytes to convert in string
"""
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return unpack_from("<H", c, o)[0]
def si16le(c, o=0):
"""
Converts a 2-bytes (16 bits) string to a signed integer.
c: string containing bytes to convert
o: offset of bytes to convert in string
"""
return unpack_from("<h", c, o)[0]
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def i32le(c, o=0):
"""
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Converts a 4-bytes (32 bits) string to an unsigned integer.
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c: string containing bytes to convert
o: offset of bytes to convert in string
"""
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return unpack_from("<I", c, o)[0]
def si32le(c, o=0):
"""
Converts a 4-bytes (32 bits) string to a signed integer.
c: string containing bytes to convert
o: offset of bytes to convert in string
"""
return unpack_from("<i", c, o)[0]
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def i16be(c, o=0):
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return unpack_from(">H", c, o)[0]
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def i32be(c, o=0):
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return unpack_from(">I", c, o)[0]
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# 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)