Vehicle-Anti-Theft-Face-Rec.../venv/Lib/site-packages/skimage/io/_plugins/qt_plugin.py

151 lines
4.8 KiB
Python

import numpy as np
from .util import prepare_for_display, window_manager
from ..._shared.utils import warn
from qtpy.QtWidgets import (QApplication, QLabel, QMainWindow, QWidget,
QGridLayout)
from qtpy.QtGui import QImage, QPixmap
from qtpy import QtCore
# We try to acquire the gui lock first or else the gui import might
# trample another GUI's PyOS_InputHook.
window_manager.acquire('qt')
app = None
class ImageLabel(QLabel):
def __init__(self, parent, arr):
QLabel.__init__(self)
# we need to hold a reference to
# arr because QImage doesn't copy the data
# and the buffer must be alive as long
# as the image is alive.
self.arr = arr
# we also need to pass in the row-stride to
# the constructor, because we can't guarantee
# that every row of the numpy data is
# 4-byte aligned. Which Qt would require
# if we didn't pass the stride.
self.img = QImage(arr.data, arr.shape[1], arr.shape[0],
arr.strides[0], QImage.Format_RGB888)
self.pm = QPixmap.fromImage(self.img)
self.setPixmap(self.pm)
self.setAlignment(QtCore.Qt.AlignTop)
self.setMinimumSize(100, 100)
def resizeEvent(self, evt):
width = self.width()
pm = QPixmap.fromImage(self.img)
self.pm = pm.scaledToWidth(width)
self.setPixmap(self.pm)
class ImageWindow(QMainWindow):
def __init__(self, arr, mgr):
QMainWindow.__init__(self)
self.setWindowTitle('skimage')
self.mgr = mgr
self.main_widget = QWidget()
self.layout = QGridLayout(self.main_widget)
self.setCentralWidget(self.main_widget)
self.label = ImageLabel(self, arr)
self.layout.addWidget(self.label, 0, 0)
self.layout.addLayout
self.mgr.add_window(self)
self.main_widget.show()
def closeEvent(self, event):
# Allow window to be destroyed by removing any
# references to it
self.mgr.remove_window(self)
def imread(filename):
"""
Read an image using QT's QImage.load
"""
qtimg = QImage()
if not qtimg.load(filename):
# QImage.load() returns false on failure, so raise an exception
raise IOError('Unable to load file %s' % filename)
if qtimg.depth() == 1:
raise IOError('1-bit images currently not supported')
# TODO: Warn about other odd formats we don't currently handle properly,
# such as the odd 16-bit packed formats QT supports
arrayptr = qtimg.bits()
# QT may pad the image, so we need to use bytesPerLine, not width for
# the conversion to a numpy array
bytes_per_pixel = qtimg.depth() // 8
pixels_per_line = qtimg.bytesPerLine() // bytes_per_pixel
img_size = pixels_per_line * qtimg.height() * bytes_per_pixel
arrayptr.setsize(img_size)
img = np.array(arrayptr)
# Reshape and trim down to correct dimensions
if bytes_per_pixel > 1:
img = img.reshape((qtimg.height(), pixels_per_line, bytes_per_pixel))
img = img[:, :qtimg.width(), :]
else:
img = img.reshape((qtimg.height(), pixels_per_line))
img = img[:, :qtimg.width()]
# Strip qt's false alpha channel if needed
# and reorder color axes as required
if bytes_per_pixel == 4 and not qtimg.hasAlphaChannel():
img = img[:, :, 2::-1]
elif bytes_per_pixel == 4:
img[:, :, 0:3] = img[:, :, 2::-1]
return img
def imshow(arr, fancy=False):
global app
if not app:
app = QApplication([])
arr = prepare_for_display(arr)
if not fancy:
iw = ImageWindow(arr, window_manager)
else:
from .skivi import SkiviImageWindow
iw = SkiviImageWindow(arr, window_manager)
iw.show()
def _app_show():
global app
if app and window_manager.has_windows():
app.exec_()
else:
print('No images to show. See `imshow`.')
def imsave(filename, img, format_str=None):
# we can add support for other than 3D uint8 here...
img = prepare_for_display(img)
qimg = QImage(img.data, img.shape[1], img.shape[0],
img.strides[0], QImage.Format_RGB888)
if _is_filelike(filename):
byte_array = QtCore.QByteArray()
qbuffer = QtCore.QBuffer(byte_array)
qbuffer.open(QtCore.QIODevice.ReadWrite)
saved = qimg.save(qbuffer, format_str.upper())
qbuffer.seek(0)
filename.write(qbuffer.readAll().data())
qbuffer.close()
else:
saved = qimg.save(filename)
if not saved:
from textwrap import dedent
msg = dedent(
'''The image was not saved. Allowable file formats
for the QT imsave plugin are:
BMP, JPG, JPEG, PNG, PPM, TIFF, XBM, XPM''')
raise RuntimeError(msg)
def _is_filelike(possible_filelike):
return callable(getattr(possible_filelike, 'write', None))