AcquireImage

The AcquireImage function specifies the parameters for capturing a digital image and transferring it to the In-Sight vision system's processing memory.

In-Sight vision systems capture all images using asynchronous reset and progressive scan. Greyscale vision systems produce 8-bit images, while color vision systems (indicated with a C suffix) produce 24-bit images. The image acquisition process begins within approximately 250µs for all vision systems, and proceeds as follows:

The image sensor integrates light for the duration of time specified by the Exposure parameter.
The image accumulated in the image sensor is transferred, row-by-row, into a serial shift register.
For every row transfer, the sensor clocks the shift register, pixel-by-pixel, out of the image sensor through the following path:

Video amplifier -> Gain and Offset -> Analog-to-digital converter -> Vision processor memory

The memory buffer containing the acquired image is represented in the spreadsheet as an Image data structure. The Image data structure returned by AcquireImage is in turn referenced by other In-Sight spreadsheet functions that process image regions. Any function that directly or indirectly depends on acquired image data is forced to update when a new image is acquired. This relationship between the input image and other functions in the spreadsheet is what drives the execution of vision tasks on In-Sight vision systems. For more information on dependencies and cell execution order, see Spreadsheet Cell Execution.

When a spreadsheet is initially created, an AcquireImage function will automatically be added and located in cell A0. Most Vision Tool functions, as well as many other functions, take advantage of this by specifying an absolute reference to cell A0 as their default image source. For more information, see Cell References.

CAUTION: You can delete the AcquireImage function from the spreadsheet, but you should NOT do so, as it makes image acquisition impossible. If you accidentally delete the AcquireImage function in cell A0, undo the removal with the Edit > Undo menu, or press Ctrl+Z.

Note: As the AcquireImage function does not contain any arguments, the configured acquisition settings are not retained when exporting the cells as a cell template. To export the acquisition settings, add ApplyAcquisitionSettings to the spreadsheet, enable the parameters that you desire to retain, set the settings to the desired values, and then export ApplyAcquisitionSettings as a cell template. When the cell template that contains ApplyAcquisitionSettings is imported, the acquisition settings will be applied to the AcquireImage function once the ApplyAcquisitionSettings cell is executed. For more information on the spreadsheet cell templates, see Export and Import Cells To or From Templates.

AcquireImage Inputs

Parameter

Description

Trigger Mode

Defines how the device will be triggered to acquire an image.

Note: Trigger Mode is used with the dedicated acquisition trigger input line. For more information, see Configure Discrete I/O Lines.

0	Camera	Enables image acquisition on the trigger issued directly to the device.
1	Timer Interval	Enables image acquisition on triggers issued at a user specified interval.
2	Continuous (default)	Enables free running (as fast as possible) image acquisitions.
3	Manual	Enables image acquisition on the trigger issued manually by users.
4	Industrial Ethernet	Enables image acquisition on triggers originating from an Industrial Ethernet protocol.

Trigger Interval

Defines an interval, in milliseconds, between acquisitions (0-10000; default = 500). This setting is dependent on the amount of time the spreadsheet takes to complete processing the image. For example, if the Trigger Interval is set to 5,000 milliseconds, the device acquires an image every 5,000 milliseconds, provided the spreadsheet completes its image processing within 5,000 milliseconds. If not, the device acquires an image as soon as it completes processing the image.

Note: The Trigger Mode must be set to Timer Interval to enable this parameter.

Debounce (ms)

Defines the amount of time (0-65.535 milliseconds; default = 0.5) that the input trigger must remain active to be recognized as a valid trigger, when the Trigger Mode property is set to Camera.

Note: The Trigger Mode must be set to Camera to enable this parameter.

Delay (ms)

Defines the delay (0-10000 milliseconds; default = 0) between the time that a trigger to acquire an image is received, and the time device begins the image acquisition. No additional triggers are accepted during this delay period, and any received triggers during this period will result in a Missed Trigger event.

Exposure (ms)

Defines the exposure time. When the device receives an image acquisition trigger signal, light is integrated into the image sensor array for the specified duration. Shorter durations are better suited for stopping motion, but may require larger lens apertures or higher Gain settings to achieve sufficient image intensity.

In-Sight Model	Resolution	Sensor Type	Exposure Time (ms)
In-Sight D902, D902C	1920 x 1200	CMOS, global shutter	0.024 to 1000; default = 8
In-Sight D905, D905C	2448 x 2048	CMOS, global shutter	0.021 to 1000; default = 8

The In-Sight illumination accessory has a maximum strobe pulse width that is dependent on the Intensity, LED ring light color, vision system resolution and number of rows acquired. Up to a certain Exposure time, the illumination accessory will illuminate for the specified Exposure time. If the Exposure time exceeds the maximum strobe pulse width, the LED ring light will only illuminate for the maximum strobe pulse width. See the following table for the calculated maximum strobe pulse width for the supported LED ring light, intensity, and device type combinations.

Note: When working with color vision system models (In-Sight D902C, D905C), use white LED ring light only.

LED Ring Light Color	Intensity	Maximum Strobe Pulse Width (ms)
LED Ring Light Color	Intensity	D902	D902C	D905	D905C
White	100%	0.751	0.751	1.599	1.599
White	50%	1.859	1.859	3.961	3.961
Red	100%	0.867	N/A	1.847	N/A
Red	50%	2.586		5.508
IR	100%	0.838		1.599
IR	50%	2.047		3.889
Blue	100%	0.751		1.785
Blue	50%	1.826		4.361

Note: At Exposure times greater than the maximum strobe pulse width, a lower Intensity may result in brighter images, due to increased LED efficiency at a lower current.

Offset

Defines a Direct Current (DC) level that is added or subtracted from the device's analog signal before the analog-to-digital conversion. The Offset affects the image's brightness and darkness, while maintaining the dynamic range within the image. (0 to 255; default = 0)

In-Sight Model	Offset Settings
D902, D902C, D905, D905C	0 to 255; default = 0

Gain

Defines the gain of the amplifier stage that precedes the analog-to-digital conversion.

In-Sight Model	Gain Settings
D902, D902C, D905, D905C	0 to 255; default = 60

Orientation

Defines the orientation of the image.

0 = Normal (default)
1 = Flipped vertically
2 = Mirrored horizontally
3 = Rotated 180 degrees

Start Row

Defines the first row to be transferred from the image sensor into memory on the device.

Note: The value of this property is locked to 0 when using an In-Sight D900 series vision system, and cannot be changed.

Number of Rows

Defines the number of image sensor rows to be transferred into memory on the device. This is used to create partial image acquisitions, where only a specified number of image rows are used to create the output image.

Note:

This property cannot be modified when using an In-Sight D900 series vision system, and always takes the maximum number of rows supported by the device:

D902, D902C: 1200
D905, D905C: 2048

Image Buffers

Defines the number of buffers used for image acquisition, based on the resolution and RAM of the vision system.

Note:

This property cannot be modified when using an In-Sight D900 series vision system, and takes a value depending on the device type:

D902, D905: 25
D902C, D905C: 16

Illumination

The following parameters are used to configure light settings.

Note: Only the Strobe Start and Strobe Polarity parameters are available when using an In-Sight ViDi PC device.

Mode

Note: The In-Sight D900 Series Vision Systems support connecting an integrated illumination accessory to the vision system's faceplate and connecting an external light to the vision system's LIGHT connector, but does not support using both lighting devices simultaneously.

Integrated Illumination: If an integrated illumination accessory is installed to the vision system's faceplate, select the Integrated Illumination option to specify the light settings for the LED ring light.
External Illumination: If an external light is connected to the vision system's LIGHT connector, select the External Illumination to specify the light settings for the external strobe or continuous lighting device.

Intensity

Defines the effective intensity of the illumination accessory LED banks as a percentage. All LED banks share a common intensity value and the intensity is limited to 50% - 100% to ensure it is evenly distributed across all LED banks.

Integrated Illumination	50 to 100; default = 100
External Illumination	0 to 100; default = 100

Strobe Start

Defines when the strobe should pulse.

Note: The Illumination Mode must be set to External Illumination to enable this parameter.

Acquisition Start: When set to Acquisition Start, the strobe is activated when exposure begins (also includes any configured trigger delays).
Camera Trigger: When set to Camera Trigger, the strobe is activated when an acquisition trigger is received. The strobe will be active during the specified Delay (ms) period.

Strobe Polarity

Defines the signal (High or Low; default = High) that will fire a connected strobe.

Note: The Illumination Mode must be set to External Illumination to enable this parameter.

High: When set to High, the strobe will be fired when the signal is HIGH.
Low: When set to Low, the strobe will be fired when the signal is LOW.

Bank Enables

The In-Sight illumination accessory includes 8 LEDs that are separated into 4 LED banks. Select/deselect the checkbox to enable/disable the LED banks.

Note: The Illumination Mode must be set to Integrated Illumination to enable this option.

Focus

The following parameters are used to configure focus settings.

Note: The Focus parameter is only available for In-Sight D900 series vision systems.

Focus Position	Defines a value or cell reference to use as the focus position.
Focus Region	Click the button to specify the size and position of the region used to calculate the lens focus.
Autofocus	Click the button to trigger autofocus. Note: The Autofocus is only available for the vision systems with the autofocus accessory installed.

High Dynamic Range

HDR (High Dynamic Range) provides better contrast and more brightness for darker regions of an image. This effect is completed in a single acquisition.

Note: HDR is supported only on monochrome In-Sight vision systems. It is not available for color vision systems (In-Sight D902C, D905C).

The following parameters determine the HDR method and kernel size.

HDR Mode

Defines the method of HDR to use.

None (default): Do not use HDR.
HDR+: Adjusts each pixel greyscale value by considering neighboring pixels (depending on the kernel size setting). This provides more contrast in dark (underexposed) and light (overexposed) regions than HDR.
HDR: Adjusts each pixel greyscale value individually. This provides more contrast with dark (underexposed) regions on the input image.

HDR+ Kernel Size

Defines the number of pixels that are processed simultaneously with HDR+.

Small: 121 pixels (11x11 grid)
Large (default): 484 pixels (22x22 grid)

AcquireImage Outputs

Returns an Image data structure. The cell will return #ERR if an image has not yet been acquired for the job; simply trigger an acquisition (press the Trigger Once button or press F6).

Note: Functions that require an Image parameter must reference a spreadsheet cell that contains a valid Image data structure. The default Image parameter reference in all property sheets is cell A0, which contains the Image data structure returned by an AcquireImage function. But Image data structures returned by the Image functions are also valid references for Image Parameter values in property sheets.

In-Sight Model	Resolution	Greyscale/Color	Bit depth	Number of grey levels or colors	Frames Per Second (FPS)*
D902	1920 x 1200	greyscale	8-bit	256	51
D902C	1920 x 1200	color	24-bit	16 million	34
D905	2448 x 2048	greyscale	8-bit	256	26
D905C	2448 x 2048	color	24-bit	16 million	16
*Maximum frames per second are job-dependent, based on the minimum exposure for a full image frame capture using the dedicated acquisition trigger, and assumes there is no user interface connection to the vision system.

ApplyAcquisitionSettings

When you drag and drop a parameter from the AcquireImage property sheet to the spreadsheet, an ApplyAcquisitionSettings function is added to the spreadsheet, which allows you to edit acquisition parameters without opening the AcquireImage function and changes the acquisition parameters' value at runtime. On the AcquireImage property sheet, the dragged-and-dropped parameter displays a blue exclamation icon. This icon indicates that the parameter is referenced by an ApplyAcquisitionSettings function, and when you hover over the icon, the ApplyAcquisitionSettings function's cell location is displayed as a tip.

Note:

The AcquireImage property sheet also displays a blue exclamation icon when an associated parameter is dragged and dropped from the ApplyAcquisitionSettings property sheet. For more information, see ApplyAcquisitionSettings
If a parameter is referenced by multiple ApplyAcquisitionSettings functions, the icon indicates the ApplyAcquisitionSettings functions' cell locations (up to five locations).
If you uncheck a parameter on the ApplyAcquisitionSettings property sheet, the associated parameter's blue exclamation icon no longer displays in the AcquireImage property sheet.

GigE Feature Access

Note: The GigE Feature Access button is only available when a GigE camera is connected to an In-Sight ViDi PC.

To open the GigE Feature Access dialog, click the GigE Feature Access button in the AcquireImage property sheet. The GigE Feature Access dialog is used to examine or modify the XML-defined properties for the GigE Vision camera you are using.

Enter the XML node name in the Feature field.
Click the Read button to read the value of the node and update the Value field.
Click the Write button to attempt to write whatever value is in the Value field to the node.
Click the Execute button to attempt to execute the command feature specified in the Feature field.