def newToQImage(array):
"""Converts a numpy array to a QImage
A Python version of PyQt4.Qwt5.toQImage(array) in PyQwt >= 5.2.
Function written by Gerard Vermeulen
"""
if array.ndim != 2:
raise RuntimeError('array must be 2-D')
height, width = array.shape
if array.dtype == numpy.uint8:
# image = QImage(array, width, height, QImage.Format_Indexed8)
# The next statement shows that QImage does not increase the
# reference count of the buffer object to keep the data valid.
image = Qt.QImage(
array.tostring(), width, height, Qt.QImage.Format_Indexed8)
image.setNumColors(256)
for i in range(256):
image.setColor(i, qRgb(i, i, i))
return image
elif array.dtype == numpy.uint32:
image = Qt.QImage(
array.tostring(), width, height, Qt.QImage.Format_ARGB32)
return image
else:
raise RuntimeError('array.dtype must be uint8 or uint32')
def oldToQImage(array):
"""Converts a numpy array to a QImage
A Python version of PyQt4.Qwt5.toQImage(array) in PyQwt < 5.2.
Function written by Gerard Vermeulen
"""
if array.ndim != 2:
raise RuntimeError('array must be 2-D')
nx, ny = array.shape # width, height
xstride, ystride = array.strides
if array.dtype == numpy.uint8:
image = QImage(nx, ny, QImage.Format_Indexed8)
f_array = numpy.reshape(array,(nx*ny,),order='F')
for j in range(ny):
pointer = image.scanLine(j)
pointer.setsize(nx*array.itemsize)
memory = numpy.frombuffer(pointer, numpy.uint8)
first_value = j*nx
last_value = (j+1)*nx
memory[:] = f_array[first_value:last_value]
image.setColorCount(256)
for i in range(256):
image.setColor(i, qRgb(i, i, i))
return image
elif array.dtype == numpy.uint32:
image = Qt.QImage(
array.tostring(), width, height, Qt.QImage.Format_ARGB32)
f_array = numpy.reshape(array,(nx*ny,),order='F')
for j in xrange(ny):
pointer = image.scanLine(j)
pointer.setsize(nx*array.itemsize)
memory = numpy.frombuffer(pointer, numpy.uint32)
first_value = j*nx
last_value = (j+1)*nx
memory[:] = f_array[first_value:last_value]
return image
else:
raise RuntimeError('array.dtype must be uint8 or uint32')