def paintEvent(self, event):
# We need to preserve aspect ratio. Figure out bounding box for
# webcam image.
im_dx = self._image.width()
im_dy = self._image.height()
im_ratio = im_dx / float(im_dy)
wi_dx = self.width()
wi_dy = self.height()
wi_ratio = wi_dx / float(wi_dy)
if wi_ratio > im_ratio: # Need to pad on sides
xmin = wi_dx / 2. - wi_dy / 2. * im_ratio
ymin = 0.
width = wi_dy * im_ratio
height = wi_dy
else: # Need to pad on top/bottom
xmin = 0.
ymin = wi_dy / 2. - wi_dx / 2. / float(im_ratio)
width = wi_dx
height = wi_dx / float(im_ratio)
painter = QtGui.QPainter(self)
painter.drawImage(QtCore.QRect(xmin, ymin, width, height), self._image)
def _update_intensity_label(self, x, y):
lbl = self._intensity_label(x, y)
self.label_widget.setText(lbl)
fm = self.label_widget.fontMetrics()
w, h = fm.width(lbl), fm.height()
g = QtCore.QRect(20, self.central_widget.geometry().height() - h, w, h)
self.label_widget.setGeometry(g)