User`s manual

STOC USER’S MANUAL ©2005 VIDERE DESIGN
color image in 8 bits; hence, to send disparity and the color image,
PROC_MODE_DISPARITY_RAW sends the original left Bayer image
(unrectified). Color processing and rectification then takes place on the PC.
To send just the original images to the PC, use PROC_MODE_OFF. In this
mode, the STOC/-C functions just like an ordinary STH-DCSG/-C.
In the smallv application, various combinations of requested features will
put the STOC into one of the modes above. In general, smallv will try to
keep as much processing on the STOC as possible. For example,
requesting Stereo and Warp, without color, will put the STOC into
PROC_MODE_DISPARITY.
If the Proc Capable button is turned off, then the STOC will revert to
PROC_MODE_OFF, and all processing will take place on the PC.
Under program control, the processing mode can be changed using the
svsVideoImages object controlling the stereo device. The following
member function will set the mode.
bool SetProcMode(proc_mode_type mode);
enum proc_mode_type
{
PROC_MODE_OFF = 0,
PROC_MODE_NONE,
PROC_MODE_TEST,
PROC_MODE_RECTIFIED,
PROC_MODE_DISPARITY,
PROC_MODE_DISPARITY_RAW
};
3.3 Disparity images
The STOC processing board produces a disparity image, which encodes the
range to objects in the scene. The disparity image has high value (brighter)
when an object is closer, and lower value when it is further away. In
addition, there are filters that eliminate bad stereo matches – these will
appear as dark areas in the image.
Figure 3-3 An image from the STOC
device, and the corresponding disparity image.
shows a typical disparity
image from the device.
The disparity image is 10 bits in depth. The search area for stereo matches
between left and right images is 64 pixels (6 bits). In addition, the match is
interpolated to 1/16 of a pixel, giving and additional 4 bits. The
relationship between disparity and 3D XYZ coordinates depends on the
lenses and imager characteristics – see the SVS Users’ Manual and the
Calibration Addendum for more technical information. There are functions
in SVS to translate the disparity image into XYZ points.
Format Submode
Y UV NAME
LO RO
PROC_MODE_OFF,
PROC_MODE_NONE
LR RR
PROC_MODE_RECTIFIED
LR D
PROC_MODE_DISPARITY
LO D
PROC_MODE_DISPARITY_RAW
Format 0, Mode 3
YUV 16 bits
TP TP
PROC_MODE_TEST
Table 2 Submodes for the STOC YUV format.
Figure 3-3 An image from the STOC device, and the corresponding
disparity image.
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