Is_Aoi - THORLABS DCU223x Operation Manual And Sdk

4.3.3 is_AOI

USB 2.0
USB 3.0
Syntax
INT is_AOI (HIDS hCam, UINT nCommand, void* pParam, UINT nSizeOfParam)
Description
is_AOI() can be used to set the size and position of an
AOIs can be defined:
Image AOI – display of an image portion
Auto Brightness AOI – reference area of interest for automatic brightness control
Auto Whitebalance AOI – reference area of interest for automatic white balance control
The nCommand input parameter is used to select the function mode. The pParam input parameter depends on the
selected function mode. If you select functions for setting or returning a value, pParam contains a pointer to a
variable of the UINT type. The size of the memory area to which pParam refers is specified in the nSizeOfParam
input parameter.
Note
Previous AOI functions
The is_AOI() function comprises all the functions for setting and positioning an AOI. The following uc480 API
commands are therefore obsolete:
is_SetAOI()
414
is_SetImageAOI()
is_SetImageSize()
is_SetImagePos()
See also Obsolete functions
AOI for automatic image control
The AOI for automatic brightness control (AES/AGC) and automatic white balance (AWB) defaults to the same size
as the current image (i.e. the image AOI).
After changes to the image geometry (by resetting an image AOI, by binning or subsampling), the AOIs for
automatic image control will always be reset to the image AOI value. This means that it might be necessary to set
the AOIs for auto brightness/auto white balance again manually.
Fast changes of AOI position
Using the IS_AOI_IMAGE_SET_POS_FAST command, you can change the positions of AOIs very quickly.
Executing this command takes just a few milliseconds. When using this command, a few special requirements
have to be met:
The command
IS_AOI_IMAGE_SET_POS_FAST_SUPPORTED command, you can check whether your sensor supports fast
position changes.
Hot pixel correction has to be disabled (see
Image capture is not suspended for fast AOI position changes. As a result, when you call the command, a
number of images might still be transferred with the old AOI position if they were in the driver buffer at that
moment.
Notes
1. Changing the image size
When changing the size of the AOI, please make sure that the selected image memory is large enough. If it
isn't, allocate a new image memory (see
Changes to the image size affect the value ranges of the frame rate and exposure time. After executing
is_AOI(), calling the following functions is recommended in order to keep the defined camera settings:
© 2013 Thorlabs GmbH
USB 2.0
USB 3.0
434
438
435
379
is currently not
is_HotPixel()
is_AllocImageMem()
area of interest (AOI)
supported by all
).
260
).
157
4 Programming (SDK)
within an image. The following
34
DCx Cameras. With the
159