在 PySide2 中使用自定义图像提供程序进行 16 位灰度图像处理

Question

I have a PySide2 project where I've defined a custom image provider, relaying images from a camera to an image control in QtQuick. The images are 16-bit grayscale arrays, so I'd prefer to simply relay this image data directly to the display. Raw image data (self.image) is processed and converted to a QImage via the following line:

img = QImage(self.image, w, h, line_len, QImage.Format_Grayscale8)

This, of course, requires that I resample the data from 16 bit (ushort) to 8 bit (uint) prior to display. Instead, I tried calling directly the 16-bit format:

img = QImage(self.image, w, h, line_len, QImage.Format_Grayscale16)

But this throws an error:

AttributeError: type object 'PySide2.QtGui.QImage' has no attribute 'Format_Grayscale16'

I'm running PySide2 version 5.13.2, and the Qt documentation says that Format_Grayscale16 was available from Qt 5.13 (not to mention it seems to exist in my local QImage class, since PyCharm gives me the auto-complete option). What am I doing wrong here?

Answer 1

It is recommended that when compiling a specific version of PySide2 then the same version of Qt is used, but that is not a mandatory rule so if the pyside2 that is used is not officially provided then the previous recommendation was not necessarily met. If you want to know the version of pyside2 and qt you can use the following commands, respectively:

python -c "from PySide2 import __version__; print('PySide2 version', __version__)"
python -c "from PySide2.QtCore import qVersion; print('Qt version', qVersion())"

For PyQt5 you can use:

python -c "from PyQt5.QtCore import PYQT_VERSION_STR; print('PyQt5 version', PYQT_VERSION_STR)"
python -c "from PyQt5.QtCore import QT_VERSION_STR; print('Qt version', QT_VERSION_STR)"

As the OP points out in the comments, he is using anaconda which compiles manually so it does not meet the initial recommendation (uses Qt 5.12.5). So the solution is to use official PySide2 using pip:

python -m pip install pyside2