Videre Design STH-DCSG, Руководство пользователя

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STH-DCSG U
SER
’
S
M
ANUAL
©
2005 V
IDERE
D
ESIGN
9
data type, sending the left stereo image in Y, and the right image in the UV
pixels.
Each image from the stereo camera has 8-bit pixels. In the case of the color
version (STH-DCSG-C), the color information is encoded as a Bayer
pattern in the same 8-bit pixel image.
On the host computer, the SVS interface software takes the YUV stream
and parses it into the left and right images, making them available as
separate images in computer memory. It also performs color processing,
for the STH-DCSG-C, converting the Bayer pattern into full-color RGB
images.
The STH-DCSG also has a subwindow mode, in which only the center
portion of the image is returned. See Section 7.4 for full information on the
modes and resolutions for the STH-DCSG.
For the monochrome device only , smaller frame sizes are also available
using on-chip binning . Binning averages neighboring pixels to produce a
smaller image with improved noise characteristics.
3.3 50 Hz Operation
Indoor lighting, especially from fluorescent fixtures, can oscillate at the
frequency of the electrical supply. If the image frame rate does not divide
evenly into this frequency, there can be moving horizontal bands of
alternating light and dark moving in the output.
For countries with 60 Hz power such as the United State, the frame rates in
the third column of Table 1 are ideal. In many other countries, the
Left
Imager Right
Imager
Interlace
Electronics
Imager
module
1394
Interface
Electronics
1394
module
8-bit pixels
12 MHz per
imager
Interlaced
pixels
24 MHz
1394
Digital
Cable
1394
imaging
commands
Digital
Video
Stream 1394
commands
Figure 3-2 Schematic of the STH-DCSG/-C electronics.
Format Frame
size
Frame
rate, 60 Hz
(default) Frame
rate, 50 Hz
option
Format 0, Mode 3
YUV 16 bits
Left image on Y, right image
on UV 640x480 3.75, 7.5,
15, 30 Hz
3.125, 6.25,
12.5 25 Hz
Format 0, Mode 1
YUV 16 bits
Left image on Y, right image
on UV 320x240 7.5, 15, 30,
60 Hz
6.25, 12.5,
25, 50 Hz
Table 1 Frame formats and sizes for the STH-DCSG/-C.