def updateQImage(qimage, data, vmin = None, vmax = None, cmap = cmap_wjet):
"""
Modify a QImage in place from data array.
Like :func:`createQImage`, but instead of creating a new QImage,
this function updates an existing QImage. The size of the image
must not change.
:param qimage: (QImage) QImage object to be updated.
:param data: (ndarray) Array containing the data values.
:param vmin: (float) Minimum data value or None.
:param vmax: (float) Maximum data value or None.
:param cmap: (dict) Colormap for converting the data.
:returns: (QImage) Image from given data.
Example::
import numpy as np
from qao.plot.image import createQImage, updateQImage
data = np.random.rand(200, 200)
qimage = createQImage(np.zeros_like(data))
updateQImage(qimage, data)
qimage.save("random.png")
"""
data, vmin, vmax = __checkTypes(data, vmin, vmax)
# write rgb data to existing QImage
assert data.size == (qimage.height()*qimage.width()), "invalid size"
rgbdata_cobject = qimage.bits().ascobject()
cmapping_cobject(data, rgbdata_cobject, vmin, vmax, cmap["r_map"], cmap["g_map"], cmap["b_map"])
def createQImage(data, vmin = None, vmax = None, cmap = cmap_wjet):
"""
Create QImage from data array using a color-map.
The minimum and maximum value for scaling the colormap is
determined from `data` unless specified by `vmin` and `vmax`.
The output will be a 24bit RGB QImage that can be used within
graphical user applications or saved to files.
:param data: (ndarray) Array containing the data values.
:param vmin: (float) Minimum data value or None.
:param vmax: (float) Maximum data value or None.
:param cmap: (dict) Colormap for converting the data.
:returns: (QImage) Image from given data.
Example::
import numpy as np
from qao.plot.image import createQImage, cmap_jet
data = np.random.rand(200, 200)
qimage = createQImage(data, cmap = cmap_jet)
qimage.save("random.png")
"""
data, vmin, vmax = __checkTypes(data, vmin, vmax)
# write rgb data to new QImage
qimage = QtGui.QImage(data.shape[1], data.shape[0], QtGui.QImage.Format_RGB32)
rgbdata_cobject = qimage.bits().ascobject()
cmapping_cobject(data, rgbdata_cobject, vmin, vmax, cmap["r_map"], cmap["g_map"], cmap["b_map"])
return qimage
