ViewCast Osprey PCI, Руководство пользователя

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Setting Driver Properties
38 ViewCast
Note: While it is possible to expose and enumerate up to 10 filters per device, the practical number of
filters depends on your hardware. When video is being directly rendered to the screen, the video
format and type of renderer used can make a major difference in system performance and in the
number of streams that are possible. If multiple capture devices are in the system, the number of
filters is the total across all the devices; in addition, some types of processing such as
deinterlacing and gamma correction that are performed once per device may in this case occur
multiple times. So, in summary, a high-end, multicore or multiprocessor system can support 5, 6,
or more concurrent filters on one device if the processing per filter is light; but only 2 or 3 if the
processing load inside or outside of the driver is particular heavy.
Multiple Filters - Use this mode if you are using Osprey custom cropping, logos (watermarks), and
NTSC Closed Caption rendering, and want each stream to have separate settings for these items.
This mode is definitely more complicated than the One Filter option just described – so only use it if
you are sure you need it.
Note: You do not have to use this mode if the only things you want to be different on different streams
are the video output size, color format, and/or frame rate. The application stores these settings,
not the driver.
The term “multiple filters” refers to the method of saving and accessing these different settings. You
can have 2 to 9 different filters, each holding different settings. The number of settings is
determined by the edit box,
Show [4] filters per device .
For example suppose you elect to have 4 filters per device, each with separate crop, logo, and
caption settings. Let’s say the underlying device has had the name
Osprey 230 Video Device 1 . With
SimulStream enabled, when you open a list of capture devices, you will see Osprey 230 Video
Device 1.1 , Osprey 230 Video Device 1.2 , and …1.3 and …1.4 .
To set the custom properties for one of these filter, select it from the device list and open the driver
properties dialog. The title at the top of the dialog will confirm that you are setting up, for example,
Osprey 230 Video Device 1.2. When you set crop, logo, and caption settings, these will be saved
separately for Device 1.2 and will not affect Devices 1.1, 1.3, or 1.4. Settings that are not per-filter –
such as Reference Size or the Video Proc Amp settings – will affect all filters on the underlying
Osprey 230 Video Device 1.
Later, whenever you select one of the four filters as your capture filter, the Osprey custom crop,
logo, and caption settings previously set for that filter will be selected automatically.
You can have multiple streams on each filter. For example, you could have four streams consisting of
two instances of Osprey 230 Video Device 1.1, and two instances of Osprey 230 Video Device 1.2.
The first two instances will have filter 1.1’s settings; the second two instances filter 1.2’s settings.
This setting affects all devices served by the currently accessed driver. The driver will advise you to
restart the system or your application if this is needed.