Hello,
Here is a problem I encountered, and the solution I stumbled on. I thought I'd share both in case others encounter it too:
On Windows XP, when acquiring and displaying a non-square image from a PCI-1424 via .NET WPF, I saw periodic glitches in the video image (white vertical lines). These glitches were simultaneous with large curved deflections in the FRAME_DONE timing signal, as viewed on an external oscilloscope. The glitch frequency appeared to be a function of frame rate and aspect-ratio.
This only occurred when calling ‘WritePixels()’ on a `WriteableBitmap` object, or ‘Invalidate’ on an `InteropBitmap` object, and only when the object was bound to an Image control. Video playback via GDI was problem free.
After many failed troubleshooting attempts, as a last-ditch effort I wiped the hard disk and installed Windows Vista. That fixed it.
Hardware:
- Dell T3400 workstation with NVidia NVS Quadro 290 graphics
- Hamamatsu Orca ER camera attached to a NI PCI 1424
Software:
- Problem on Windows XP SP3; Fixed on Windows Vista SP2
- NVidia graphics driver v191.00 (WHQL)
- NI Vision Acquisition 2009 software / IMAQ 4.3
- WPF graphics on .NET 3.5 SP1, using the NI IMAQ API for .NET 3.5
Besides the operating system change, the only software change was in the Nvidia graphics driver (they have a different v191 driver for XP than for Vista)
I hope this helps someone. And if anyone has any idea what might have been the underlying cause, I'd be curious to hear it.
Best,
Gabriel
Message Edited by Gabriel-r on 11-06-2009 04:02 AM
