ViewCast Osprey PCI, User Manual

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AVStream Driver Reference Information
84 ViewCast
Vertical Interval Timecode (VITC)
Vertical Interval Timecode (VITC) data is embedded in the Vertical Blanking Intervals (VBIs) of some
video content. Timecodes mark each frame with an hour / minute / second / framenumber marking
that can be use for frame-precise editing.
Figure 59. ActiveMovie Window
The current Osprey VITC implementation is preliminary in nature. The features and method of
implementation are subject to change. We invite comments on the timecode-related capabilities
that you need for your application.
Osprey’s approach to VITC is to invisibly watermark the video bits of each outgoing video frame with
its timestamp data. The illustration shows a timecode extracted from a watermarked frame and
rendered as text on the video. Four elements are used to produce it:

The device extracts timecode data from the vertical blanking interval (VBI) waveform.

The driver watermarks timecode
into the video preview or capture pin’s output data.

A custom filter decodes the watermark from the video and renders it.

A GraphEdit graph combines the required filters.