Pillow/src/PIL/ImageQt.py
2024-08-26 23:49:03 +10:00

217 lines
6.6 KiB
Python

#
# The Python Imaging Library.
# $Id$
#
# a simple Qt image interface.
#
# history:
# 2006-06-03 fl: created
# 2006-06-04 fl: inherit from QImage instead of wrapping it
# 2006-06-05 fl: removed toimage helper; move string support to ImageQt
# 2013-11-13 fl: add support for Qt5 (aurelien.ballier@cyclonit.com)
#
# 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 io import BytesIO
from typing import TYPE_CHECKING, Any, Callable, Union
from . import Image
from ._util import is_path
if TYPE_CHECKING:
import PyQt6
import PySide6
from . import ImageFile
QBuffer: type
QByteArray = Union[PyQt6.QtCore.QByteArray, PySide6.QtCore.QByteArray]
QIODevice = Union[PyQt6.QtCore.QIODevice, PySide6.QtCore.QIODevice]
QImage = Union[PyQt6.QtGui.QImage, PySide6.QtGui.QImage]
QPixmap = Union[PyQt6.QtGui.QPixmap, PySide6.QtGui.QPixmap]
qt_version: str | None
qt_versions = [
["6", "PyQt6"],
["side6", "PySide6"],
]
# If a version has already been imported, attempt it first
qt_versions.sort(key=lambda version: version[1] in sys.modules, reverse=True)
for version, qt_module in qt_versions:
try:
qRgba: Callable[[int, int, int, int], int]
if qt_module == "PyQt6":
from PyQt6.QtCore import QBuffer, QIODevice
from PyQt6.QtGui import QImage, QPixmap, qRgba
elif qt_module == "PySide6":
from PySide6.QtCore import QBuffer, QIODevice
from PySide6.QtGui import QImage, QPixmap, qRgba
except (ImportError, RuntimeError):
continue
qt_is_installed = True
qt_version = version
break
else:
qt_is_installed = False
qt_version = None
def rgb(r: int, g: int, b: int, a: int = 255) -> int:
"""(Internal) Turns an RGB color into a Qt compatible color integer."""
# use qRgb to pack the colors, and then turn the resulting long
# into a negative integer with the same bitpattern.
return qRgba(r, g, b, a) & 0xFFFFFFFF
def fromqimage(im: QImage | QPixmap) -> ImageFile.ImageFile:
"""
:param im: QImage or PIL ImageQt object
"""
buffer = QBuffer()
qt_openmode: object
if qt_version == "6":
try:
qt_openmode = getattr(QIODevice, "OpenModeFlag")
except AttributeError:
qt_openmode = getattr(QIODevice, "OpenMode")
else:
qt_openmode = QIODevice
buffer.open(getattr(qt_openmode, "ReadWrite"))
# preserve alpha channel with png
# otherwise ppm is more friendly with Image.open
if im.hasAlphaChannel():
im.save(buffer, "png")
else:
im.save(buffer, "ppm")
b = BytesIO()
b.write(buffer.data())
buffer.close()
b.seek(0)
return Image.open(b)
def fromqpixmap(im: QPixmap) -> ImageFile.ImageFile:
return fromqimage(im)
def align8to32(bytes: bytes, width: int, mode: str) -> bytes:
"""
converts each scanline of data from 8 bit to 32 bit aligned
"""
bits_per_pixel = {"1": 1, "L": 8, "P": 8, "I;16": 16}[mode]
# calculate bytes per line and the extra padding if needed
bits_per_line = bits_per_pixel * width
full_bytes_per_line, remaining_bits_per_line = divmod(bits_per_line, 8)
bytes_per_line = full_bytes_per_line + (1 if remaining_bits_per_line else 0)
extra_padding = -bytes_per_line % 4
# already 32 bit aligned by luck
if not extra_padding:
return bytes
new_data = [
bytes[i * bytes_per_line : (i + 1) * bytes_per_line] + b"\x00" * extra_padding
for i in range(len(bytes) // bytes_per_line)
]
return b"".join(new_data)
def _toqclass_helper(im: Image.Image | str | QByteArray) -> dict[str, Any]:
data = None
colortable = None
exclusive_fp = False
# handle filename, if given instead of image name
if hasattr(im, "toUtf8"):
# FIXME - is this really the best way to do this?
im = str(im.toUtf8(), "utf-8")
if is_path(im):
im = Image.open(im)
exclusive_fp = True
assert isinstance(im, Image.Image)
qt_format = getattr(QImage, "Format") if qt_version == "6" else QImage
if im.mode == "1":
format = getattr(qt_format, "Format_Mono")
elif im.mode == "L":
format = getattr(qt_format, "Format_Indexed8")
colortable = [rgb(i, i, i) for i in range(256)]
elif im.mode == "P":
format = getattr(qt_format, "Format_Indexed8")
palette = im.getpalette()
assert palette is not None
colortable = [rgb(*palette[i : i + 3]) for i in range(0, len(palette), 3)]
elif im.mode == "RGB":
# Populate the 4th channel with 255
im = im.convert("RGBA")
data = im.tobytes("raw", "BGRA")
format = getattr(qt_format, "Format_RGB32")
elif im.mode == "RGBA":
data = im.tobytes("raw", "BGRA")
format = getattr(qt_format, "Format_ARGB32")
elif im.mode == "I;16":
im = im.point(lambda i: i * 256)
format = getattr(qt_format, "Format_Grayscale16")
else:
if exclusive_fp:
im.close()
msg = f"unsupported image mode {repr(im.mode)}"
raise ValueError(msg)
size = im.size
__data = data or align8to32(im.tobytes(), size[0], im.mode)
if exclusive_fp:
im.close()
return {"data": __data, "size": size, "format": format, "colortable": colortable}
if qt_is_installed:
class ImageQt(QImage): # type: ignore[misc]
def __init__(self, im: Image.Image | str | QByteArray) -> None:
"""
An PIL image wrapper for Qt. This is a subclass of PyQt's QImage
class.
:param im: A PIL Image object, or a file name (given either as
Python string or a PyQt string object).
"""
im_data = _toqclass_helper(im)
# must keep a reference, or Qt will crash!
# All QImage constructors that take data operate on an existing
# buffer, so this buffer has to hang on for the life of the image.
# Fixes https://github.com/python-pillow/Pillow/issues/1370
self.__data = im_data["data"]
super().__init__(
self.__data,
im_data["size"][0],
im_data["size"][1],
im_data["format"],
)
if im_data["colortable"]:
self.setColorTable(im_data["colortable"])
def toqimage(im: Image.Image | str | QByteArray) -> ImageQt:
return ImageQt(im)
def toqpixmap(im: Image.Image | str | QByteArray) -> QPixmap:
qimage = toqimage(im)
return getattr(QPixmap, "fromImage")(qimage)