Dalsa Piranha3, User Manual

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Piranha 3 User Manual
DALSA 03-032-10216-02
33
3.3.3 Setting a Pretrigger
Purpose: Some framegrabbers require a small amount of time (several
pixels) to acquire data from a camera. Pretrigger allows the
framegrabber set up time by sending the LVAL signal high several
pixels earlier than valid data.
Syntax:
spt i
Syntax Elements:
i
Pretrigger in a range from
0
to
16
.
3.4 Data Processing
3.4.1 Setting a Region of Interest (ROI)
Purpose: Sets the pixel range used to collect the end-of-line statistics and sets
the region of pixels used in the
ccg
,
cao
,
gl
,
gla
,
ccf
,
ccp
, and
cpa
commands.
In most applications, the field of view exceeds the required object
size and these extraneous areas should be ignored. It is
recommended that you set the region of interest a few pixels inside
the actual useable image.
Syntax:
roi x1 y1 x2 y2
Syntax Elements:
x1
Pixel start number. Must be less than the pixel end number in a
range from
1
to
sensor resolution
.
y1
Column start number. Since the Piranha3 is a line scan camera,
this value must be
1
.
x2
Pixel end number. Must be greater than or equal to the pixel
start number in a range from
2
to
sensor resolution
.
y2
Column end number. Since the Piranha3 is a line scan camera,
this value must be
1
.
Notes: •
To return the current region of interest, use the commands
gcp
or
get roi
.
Related Commands
ccg
,
cao
,
gl
,
gla
,
ccf
,
ccp , els
Example:
roi 10 1 50 1
3.4.2 Analog and Digital Signal Processing Chain
Processing Chain Overview and Description
The following diagram shows a simplified block diagram of the camera’s analog and
digital processing chain. The analog processing chain begins with an analog gain