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Chapter 5: Analog Video Driver Properties
Reference Size
The reference size information is always read-
only on this dialog tab. It is determined by
settings made on other tabs – specifically, the
Input tab, where a 525-line or 625-line standard
is selected, and the RefSize tab, where NTSC
vertical sizing is selected. The read-only text
box describes which of these options is currently
governing the reference size.
The reference width and height represent the
full uncropped size of the incoming video. Your
crop settings are interpreted relative to this
reference size. For example, if you are capturing
525-line video, with a reference size of 720x480,
and your crop rectangle is (0, 0, 720, 480), then
your video is effectively uncropped. But if you
are capturing 625-line video, with a reference
size of 720x576, the same (0, 0, 720, 480) crop
specification will truncate the bottom edge of the
video.
Granularity
Most video data capture formats impose
restrictions on the possible width and/or
height of the video, referred to as “granularity”
restrictions. For example, the I420 capture
format requires that the capture width be a
multiple of 16 and the capture height be a
multiple of 2. The Rgb32 format, on the other
hand, imposes no restrictions at all.
The granularities of the supported color formats
are shown on table 1.
The Granularity controls show you the
granularity restrictions for the selected video
format, and assist you in choosing crop and
output sizes that observe those restrictions.
When the Crop tab is opened, the drop boxes are
initialized to the current or most recently used
formats for the selected pins.
If Pin Select is set to Capture or Preview, only
the corresponding drop box is selected. The
two small read-only edit boxes to the right
of the group show the horizontal and vertical
granularities for that pin’s format.
Format
Horizontal
Vertical
YUY2
2
1
UYUV
2
1
I420
16
2
YVU9
16
4
RGB55
2
1
RGB24
4
1
RGB32
1
1
Greyscale
4
1
[none]
1
1
[any]
16
4
Granularities of Supported Color Formats
1
Summary of Contents for Osprey-300
Page 1: ...Osprey 300 User s Guide...
