Pillow/PIL/ImageQt.py
2016-09-24 19:10:46 +10:00

200 lines
5.6 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 PIL import Image
from PIL._util import isPath
from io import BytesIO
qt_is_installed = True
qt_version = None
try:
from PyQt5.QtGui import QImage, qRgba, QPixmap
from PyQt5.QtCore import QBuffer, QIODevice
qt_version = '5'
except (ImportError, RuntimeError):
try:
from PyQt4.QtGui import QImage, qRgba, QPixmap
from PyQt4.QtCore import QBuffer, QIODevice
qt_version = '4'
except (ImportError, RuntimeError):
try:
from PySide.QtGui import QImage, qRgba, QPixmap
from PySide.QtCore import QBuffer, QIODevice
qt_version = 'side'
except ImportError:
qt_is_installed = False
def rgb(r, g, b, a=255):
"""(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):
"""
:param im: A PIL Image object, or a file name
(given either as Python string or a PyQt string object)
"""
buffer = QBuffer()
buffer.open(QIODevice.ReadWrite)
# preserve alha 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()
try:
b.write(buffer.data())
except TypeError:
# workaround for Python 2
b.write(str(buffer.data()))
buffer.close()
b.seek(0)
return Image.open(b)
def fromqpixmap(im):
return fromqimage(im)
# buffer = QBuffer()
# buffer.open(QIODevice.ReadWrite)
# # im.save(buffer)
# # What if png doesn't support some image features like animation?
# im.save(buffer, 'ppm')
# bytes_io = BytesIO()
# bytes_io.write(buffer.data())
# buffer.close()
# bytes_io.seek(0)
# return Image.open(bytes_io)
def align8to32(bytes, width, mode):
"""
converts each scanline of data from 8 bit to 32 bit aligned
"""
bits_per_pixel = {
'1': 1,
'L': 8,
'P': 8,
}[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 = []
for i in range(len(bytes) // bytes_per_line):
new_data.append(bytes[i*bytes_per_line:(i+1)*bytes_per_line] + b'\x00' * extra_padding)
return b''.join(new_data)
def _toqclass_helper(im):
data = None
colortable = None
# handle filename, if given instead of image name
if hasattr(im, "toUtf8"):
# FIXME - is this really the best way to do this?
if str is bytes:
im = unicode(im.toUtf8(), "utf-8")
else:
im = str(im.toUtf8(), "utf-8")
if isPath(im):
im = Image.open(im)
if im.mode == "1":
format = QImage.Format_Mono
elif im.mode == "L":
format = QImage.Format_Indexed8
colortable = []
for i in range(256):
colortable.append(rgb(i, i, i))
elif im.mode == "P":
format = QImage.Format_Indexed8
colortable = []
palette = im.getpalette()
for i in range(0, len(palette), 3):
colortable.append(rgb(*palette[i:i+3]))
elif im.mode == "RGB":
data = im.tobytes("raw", "BGRX")
format = QImage.Format_RGB32
elif im.mode == "RGBA":
try:
data = im.tobytes("raw", "BGRA")
except SystemError:
# workaround for earlier versions
r, g, b, a = im.split()
im = Image.merge("RGBA", (b, g, r, a))
format = QImage.Format_ARGB32
else:
raise ValueError("unsupported image mode %r" % im.mode)
# must keep a reference, or Qt will crash!
__data = data or align8to32(im.tobytes(), im.size[0], im.mode)
return {
'data': __data, 'im': im, 'format': format, 'colortable': colortable
}
if qt_is_installed:
class ImageQt(QImage):
def __init__(self, im):
"""
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)
QImage.__init__(self,
im_data['data'], im_data['im'].size[0],
im_data['im'].size[1], im_data['format'])
if im_data['colortable']:
self.setColorTable(im_data['colortable'])
def toqimage(im):
return ImageQt(im)
def toqpixmap(im):
# # This doesn't work. For now using a dumb approach.
# im_data = _toqclass_helper(im)
# result = QPixmap(im_data['im'].size[0], im_data['im'].size[1])
# result.loadFromData(im_data['data'])
# Fix some strange bug that causes
if im.mode == 'RGB':
im = im.convert('RGBA')
qimage = toqimage(im)
return QPixmap.fromImage(qimage)