Video formats, modes and bandwidth
MARLIN Technical Manual
V2.4.0
149
Area of interest (AOI)
The camera’s image sensor has a defined resolution. This indicates the max-
imum number of lines and pixels per line that the recorded image may have.
However, often only a certain section of the entire image is of interest. The
amount of data to be transferred can be decreased by limiting the image to
a section when reading it out from the camera. At a lower vertical resolution
the sensor can be read out faster and thus the frame rate is increased.
While the size of the image read out for most other video formats and modes
is fixed by the IIDC specification, thereby determining the highest possible
frame rate, in Format_7 mode the user can set the
upper left corner
and
width and height
of the section (area of interest = AOI) he is interested in
to determine the size and thus the highest possible frame rate.
Setting the AOI is done in the IMAGE_POSITION and IMAGE_SIZE registers.
Attention should be paid to the increments entered in the UNIT_SIZE_INQ
and UNIT_POSITION_INQ registers when configuring IMAGE_POSITION and
IMAGE_SIZE.
IMAGE_POSITION and IMAGE_SIZE contain in the respective bits values for
the column and line of the upper left corner and values for the width and
height.
Note
L
The setting of AOIs is supported only in video Format_7.
Note
L
For more information see
Table 96: Format_7 control and sta-
tus register
on page 199.