ViewCast Osprey PCI, User Manual

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Osprey PCI User Guide
ViewCast 17
to the other line format while capture is running, the driver will detect this and automatically
reconfigure for the new format.
Although the driver can distinguish between 525-line and 625-line video, it does not distinguish
between color standards within the 525-line and 625-line groups. That is, it does not distinguish
between the three 525-line standards – NTSC, NTSC-Japan and PAL-M – and it does not distinguish
between the three 625-line standards – PAL-BDGHI, PAL-N and SECAM. The selection box therefore
shows the group of standards that are compatible with the current line format. The driver
remembers your most recent 525-line selection, and separately remembers your most recent 625-
line selection, and these two standards are the ones that will automatically be switched between
when the line format changes in the future. The default 525-line standard is NTSC and the default
625-line standard is PAL-BDGHI.
When no video signal is present, or if the driver cannot determine the standard of the input signal,
the selection box will say
[unrecognized] .
The basic video standard selection control is separate for each Osprey board or capture channel. The
auto-select buttons globally affect all boards of the currently selected type.
Changes to these controls take effect as soon as you click Apply or OK .
Note: When you change from a 525-line standard to a 625-line standard – whether under automatic
or manual control – you may need to adjust your frame size for best results. The driver does not do
this automatically. The latest driver attempts to give you usable video in all cases. For example,
when Post-Processing mode is enabled, if you have running PAL video at 768 x 576 output
resolution, and you switch to NSTC video, the driver will stretch the NTSC video to 768 x 576. The
preferred, unstretched size of NTSC video is 640 x 480 and you may want to set this size as a
separate step. Older versions of the driver, and the current driver when you enable Direct Mode,
cannot do this stretch, and video cannot be run until you adjust the output size.
A related point is, if you were previously running at the full PAL frame rate of 25 fps, when switching
to NSTC you also need to adjust the video rate to NTSC’s full native rate of 29.97 fps. The driver does
not do this automatically.