[PyQt] QImage.save() traceback

[Hans-Peter Jansen]

Am Dienstag, 6. Mai 2008 schrieb Sergi Blanch i Torné:
> On Tuesday 06 May 2008 13:28:50 Hans-Peter Jansen wrote:
> > Am Dienstag, 6. Mai 2008 schrieb Sergi Blanch i Torné:
> > > Hi,
> > >
> > > I'm try to save some images from a QImage object, but the save method
> > > is only responding me false. I try to fix why this method cannot do
> > > that, but I could know the real reason.
> > >
> > > Do you know how to allows this method to be more expressive to
> > > explains me something?
> >
> > Our favorite PyQt-ML mantra applies:
> >
> > Om, please provide a self contained example demonstrating your problem,
> > Om.
> >
> > Pete
>
> mmm, interesting, It can be useful (joking).

Well, while I made a funny statement, it was meant serious.

> Yes, I want to explain the 
> situation. I'm loading the image from PyTango (the tango's[1] python
> binding):
> from PyQt4 import QtCore, QtGui, Qt
> import PyTango
> attrImg = PyTango.AttributeProxy("lt/di/iba-01/ROIImage")
> imgData,imgDimX,imgDimY =
> attrImg.read().value,attrImg.read().dim_x,attrImg.read().dim_y
>
> And where we have an image composed by unsigned shorts, it needs a little
> manipulation, to have an unsigned char array, with a method like:
> 	def convertfrom(image):
> 		shift = 4
> 		return "".join(chr(i>>shift) for i in image )
>
> call like:
> imgData8 = convertfrom(imgData)
> To construct the object:
> image =
> QtGui.QImage(imgData8,imgDimX,imgDimY,imgDimX,QtGui.QImage.Format_Indexed
>8)
>
> Finally the save call is:
> image.save("/tmp/image.png","PNG")
> image.save("/tmp/image.jpg","JPG")
> image.save("/tmp/image.tiff","TIFF")
>
> And all this calls return False (and the file is not in the directory).
> The image is shown in a widget and it seems nice.

You didn't provide a self contained example again. Reduce your problem to a 
pure PyQt script, and provide the image 

> Thanks for reading
>
> /Sergi.
>
> [1]: http://www.tango-controls.org/