ViewCast Osprey PCI, Руководство пользователя

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Osprey PCI User Guide
ViewCast 75
capture pin frame rate is less than 29.97, then the preview rate will be 29.97 minus the capture
rate. In other words, the preview pin will obtain a video frame only in time slots when the capture
pin does not require one. The driver never copies video from one pin to another in Direct Mode.

On the Osprey 2X0, 300, and 440, Direct Mode supports Closed Captioning delivered to the
DirectShow CC pin, as well as to the new Osprey proprietary CC streaming interface demoed by
the CCChannels applet supplied with the driver. The Osprey 530/540/560 implements Closed
Captioning differently, and captioning of all types requires Post Processing Mode. Direct rendering
of captions on video within the driver requires Post Processing Mode for all Osprey boards.
PostProcessing Mode
Figure 53. PostProcessing Mode
Figure 53 shows a possible graph of video data flow within the driver in PostProcessing Mode. This
particular graph assumes that SimulStream is activated so that more than two video pins are
possible. There are four video output pins, represented by the pale yellow round rectangles:

The upper pin produces scaled and/or cropped I420 video, with a logo (bug) and Closed Captions
rendered on the video.

The second pin produces scaled and/or cropped YUY2 video with a logo but no captioning. In this
particular graph, the upper two pins are scaled and cropping identically, so a single scaling
operation can service both pins.

The third pin has a different scale/crop specification, so its video runs through a separate
scaler/cropper. The video is captioned and converted to RGB15.

The lower pin produces unscaled, uncropped D1 YUY2 video with no logo or captioning.
The video routed to all pins in this example is deinterlaced and gamma-corrected. Deinterlace or
inverse telecine, if used, are always applied globally to all pins, as is gamma correction. Scaling,
cropping, logoing, captioning, and color format conversion are performed separately for each pin.
Compared to Direct Mode, PostProcessing Mode adds the following capabilities:

With SimulStream disabled, there is still a maximum of one capture pin and one preview pin on the
device at a time. However, there are no restrictions on combinations of video size and rate, color
formats, or crop settings. The driver will color convert and copy video as required to deliver up to 25
or 29.97 frames per second in any format to the two pins.