#
# The Python Imaging Library.
# $Id$
#
# standard mode descriptors
#
# History:
# 2006-03-20 fl Added
#
# Copyright (c) 2006 by Secret Labs AB.
# Copyright (c) 2006 by Fredrik Lundh.
#
# See the README file for information on usage and redistribution.
#
from __future__ import annotations
import sys
from functools import lru_cache
[docs]
class ModeDescriptor:
"""Wrapper for mode strings."""
def __init__(
self,
mode: str,
bands: tuple[str, ...],
basemode: str,
basetype: str,
typestr: str,
) -> None:
self.mode = mode
self.bands = bands
self.basemode = basemode
self.basetype = basetype
self.typestr = typestr
def __str__(self) -> str:
return self.mode
[docs]
@lru_cache
def getmode(mode: str) -> ModeDescriptor:
"""Gets a mode descriptor for the given mode."""
# initialize mode cache
endian = "<" if sys.byteorder == "little" else ">"
modes = {
# core modes
# Bits need to be extended to bytes
"1": ("L", "L", ("1",), "|b1"),
"L": ("L", "L", ("L",), "|u1"),
"I": ("L", "I", ("I",), endian + "i4"),
"F": ("L", "F", ("F",), endian + "f4"),
"P": ("P", "L", ("P",), "|u1"),
"RGB": ("RGB", "L", ("R", "G", "B"), "|u1"),
"RGBX": ("RGB", "L", ("R", "G", "B", "X"), "|u1"),
"RGBA": ("RGB", "L", ("R", "G", "B", "A"), "|u1"),
"CMYK": ("RGB", "L", ("C", "M", "Y", "K"), "|u1"),
"YCbCr": ("RGB", "L", ("Y", "Cb", "Cr"), "|u1"),
# UNDONE - unsigned |u1i1i1
"LAB": ("RGB", "L", ("L", "A", "B"), "|u1"),
"HSV": ("RGB", "L", ("H", "S", "V"), "|u1"),
# extra experimental modes
"RGBa": ("RGB", "L", ("R", "G", "B", "a"), "|u1"),
"BGR;15": ("RGB", "L", ("B", "G", "R"), "|u1"),
"BGR;16": ("RGB", "L", ("B", "G", "R"), "|u1"),
"BGR;24": ("RGB", "L", ("B", "G", "R"), "|u1"),
"LA": ("L", "L", ("L", "A"), "|u1"),
"La": ("L", "L", ("L", "a"), "|u1"),
"PA": ("RGB", "L", ("P", "A"), "|u1"),
}
if mode in modes:
base_mode, base_type, bands, type_str = modes[mode]
return ModeDescriptor(mode, bands, base_mode, base_type, type_str)
mapping_modes = {
# I;16 == I;16L, and I;32 == I;32L
"I;16": "<u2",
"I;16S": "<i2",
"I;16L": "<u2",
"I;16LS": "<i2",
"I;16B": ">u2",
"I;16BS": ">i2",
"I;16N": endian + "u2",
"I;16NS": endian + "i2",
"I;32": "<u4",
"I;32B": ">u4",
"I;32L": "<u4",
"I;32S": "<i4",
"I;32BS": ">i4",
"I;32LS": "<i4",
}
type_str = mapping_modes[mode]
return ModeDescriptor(mode, ("I",), "L", "L", type_str)