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Osprey-300 User’s Guide
In theory you should be able to connect any
1394 device to the card, not just a digital video
(DV) source. In this chapter, however, we focus
on using the 1394 connector with DV devices
such as camcorders.
Most major multimedia applications will
recognize DV devices and work with them fully.
For example, we have verified that Windows
Media Encoder 9 supports a DVCam attached
to an Osprey-300. With major applications
the DV connection should “just work” and the
information here is for background and reference
only.
S
PECIFICS
OF
DV C
APTURE
The DirectShow filter used for DV capture is
called the “Microsoft DV Camera and VCR”. This
filter can capture video only, or audio and video
together. In this respect it is different from the
Osprey analog capture driver, which has logically
distinct modules for audio and video capture.
Unlike the Osprey analog driver, which captures
video into many user-selectable sizes and
formats, the DV capture filter delivers just one
format for each video standard.
For 525-line (NTSC) video, the video size is
720x480 and the video rate is 29.97 frames per
second.
For 625-line (PAL/SECAM) video, the video size
is 720x576 and the video rate is 25 frames per
second.
The video format is always a compressed format
designated with the four-character identifier
“dvsd” (case-sensitive, and lower case). In this
format, one NTSC video frame is 120,000 bytes,
and one PAL./SECAM video frame is 144,000
bytes. By comparison, one uncompressed
YUY2 NTSC frame, requiring 2 bytes per pixel,
is 691,200 bytes, and one uncompressed YUY2
half-sized frame (360x240) is 172,800 bytes;
that is to say, the half-sized YUY2 frame is
significantly larger than the full-sized dvsd frame.
Summary of Contents for Osprey-300
Page 1: ...Osprey 300 User s Guide...
