ViewCast OSPREY 240E, Руководство пользователя

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Appendix C: Troubleshooting
94 ViewCast
Poor video quality at large frame sizes
Large frame sizes with the deep pixel depth (24- or 32-bit), or complex format (YVU9 or YUV12 planar),
impose heavy demands on the PCI bus’ data transfer capacity. Our experience is that some systems
cannot handle these formats at full frame sizes.
Systems vary in their data transfer limits. The characteristics of the PCI bridge are often more important
than processor speed.
If you are having problems, we recommend you:

Use a smaller frame size (480 x 320 or less)

Use a shallower color format (RGB15 or RGB24 instead of RGB32)

Try a YUV format instead of an RGB format, and a packed format instead of a planar format
If you have a choice of PCs for video capture, try using another system with a different system board
chipset.
Multiple horizontal lines across video image
If multiple, regularly spaced, horizontal lines appear across your video image and your source material is
copyrighted and copy-protected, you are seeing Macrovision™ copy protection.
The lines can vary in color from yellow to blue to green. These lines are not present in every frame of
video. There may also be a black band at the top of the frame.
There are other brands of copy-protection besides Macrovision. Some of these brands employ similar
methods (resulting in the above) and others do not. This image is a good example of Macrovision effects
but you should find a good way, if possible, to briefly note that other forms of copy protection exist and
they may have different effects on the picture.
Cannot play back recorded audio
If you have a sound card installed, you should be able to hear audio when you play back recorded audio.
Verify that the volume control for your playback device is not muted.
Verify that the selected playback device is your sound card. Some Windows applications cannot use a
recording device unless a playback device is also installed. The Placeholder device cannot play back
recorded audio. You can use the same method to select playback device that you use when selecting the
audio source.
Audio recording control comes up with wrong
device and wrong inputs
The cause of this problem may be that you currently have or have had previously, a Video for Windows
audio capture driver installed in the system. The Osprey AVStream install process normally removes a