The Image Capture Tool (AxsunImageCaptureTool.exe) is a software interface for users of the Axsun Ethernet/PCIe DAQ. It provides a tab- and button-based GUI to easily view the captured image data transmitted from the DAQ device by exposing functionality in the AxsunOCTCapture API. It supports image capture over Gigabit Ethernet and PCIe interfaces, as well as DAQ imaging mode controls over the PCIe interface only.
The Image Capture Tool is not intended to be a fully-featured OCT image capture and analysis application, but rather a springboard for integrating the AxsunOCTCapture API into the user's custom OCT imaging application. The Image Capture Tool's primary functions include:
Retrieve and Display OCT data (unprocessed or processed images) transmitted by the DAQ
Supports all data types (8-bit, 16-bit, 32-bit, complex)
Indicate DAQ imaging mode, status of data buffer and Image_sync synchronization trigger
Save and load data buffers to/from disk
Expose secondary AxsunOCTCapture API features such as:
OpenGL-based rendering, image cropping, image averaging, etc.
Control DAQ imaging mode (PCIe interface only)
Control 2-axis galvo raster scan pattern via NI USB-6211 multi-function I/O device
The Image Capture Tool is compatible with 64-bit versions of Windows OS from Windows 7 through Windows 10. An available 1Gbps Ethernet port is required for connecting to the Ethernet DAQ via network interface, or an available PCIe Gen 1 x8 port is required for connecting to the PCIe DAQ. Because the Ethernet/PCIe DAQ performs FPGA-based OCT image formation on the DAQ board, computer requirements such as CPU speed, processor cores, and available RAM are typically satisfied by "consumer-level" personal computer platforms available from 2014 onward.
NOTE: For best performance, disable any malware protection utilites which may impede network traffic and avoid running other applications which compete for network bandwidth.
The Image Capture Tool and the AxsunOCTCapture library do not support the Axsun Camera Link DAQ. A PCIe frame grabber and its associated software is required to capture image data transmitted from the Camera Link DAQ. More information on the Axsun Camera Link DAQ can be found here.
To install the Image Capture Tool and its dependencies, download the most recent version from www.axsun.com/downloads and follow the complete software installation instructions for the Axsun Integrated Engine.
NOTE: Your screen may not match exactly with the screen representations shown in this guide, depending on your system configuration and installed firmware/software versions.
Launch the Hardware Control Tool to access high-level functionality provided by the DAQ board and any connected Laser Engines.
Launch the Image Capture Tool (AxsunImageCaptureTool.exe) and make the appropriate selection when prompted for either an Ethernet or PCIe capture session:
The selected session type will be indicated at the top of the window:
If installation errors were encountered when starting the session, the Image Capture Tool will support review of previously saved data files only. See the DAQ Troubleshooting article to overcome the errors and then try again.
The bottom of the Image Capture Tool window has lights to indicate the following when lit (also see Capture API documentation for axGetStatus()
):
Live Imaging: data is actively being transmitted from the DAQ and is being enqueued in the Main Image Buffer.
Recorded: image data displayed is/was acquired in Burst Record mode.
Image_sync Trigger Too Fast: the frequency of the trigger signal connected to the Image_sync input exceeds the allowable maximum (≈390 Hz for a laser with 100 kHz A-line rate).
Image_sync Trigger Too Slow (Force Triggered): the frequency of the trigger signal connected to the Image_sync input is too slow and the newest frame has been displayed in Force Trigger mode (see Capture API documentation for axSetTrigTimeout()
).
Use the Requested Image # field to control the image number requested for display. This can be a unique image number, or it can be set equal to -1 to display the most recently enqueued image in the buffer. Numeric indicators show the actual Returned Image #, and the Width & Depth dimensions of the displayed image (see Capture API documentation for axGetImageInfo()
and axRequestImage()
).
If Burst Recorded images are present in the Main Image Buffer, depressing the Loop button will automatically replay the recorded images from start to finish and then restart in a looping fashion.
The Image Capture Tool window contains four greyscale B-scan image indicators on separate tabs for the four possible data types that the DAQ can generate (depending on its configured bypass mode):
8-bit (unsigned)
16-bit (signed or unsigned)
32-bit (unsigned)
16-bit complex (signed with component shown on left of display and component shown on right of display)
The Image Capture Tool will automatically switch to the appropriate image indicator tab when it detects a change in the data type for the displayed image.
The Single A-Scan tab displays a graph with a single A-scan's amplitude as a function of sample number (e.g. z-dimension or depth in a processed OCT image). Select the desired A-scan to display in this graph using the A-scan # control.
NOTE: Image and graph indicators provide standard LabVIEW-based interaction tool palettes for zooming in & out, panning, changing the range of x, y, and z (colorscale) axes, etc:
​
Axis AutoScaling can be toggled by right-clicking on an axis and checking or unchecking the AutoScale selection from the pop-up menu:
​​
More details on interactive LabVIEW graph tools can be found at www.ni.com.
Some display tabs also provide Save Image buttons which export the image currently displayed in the associated indicator into a raw binary, PNG, or CSV file. Saving individual images in this fashion is an Image Capture Tool application-level function and is not supported by underlying Capture API functionality.
Additional Image Capture Tool functionality is grouped onto several tabs on the right side of the main window. The following sections highlight the relevant controls and indicators available on each tab, and their associated AxsunOCTCapture API functions. Refer to the AxsunOCTCapture API documentation and function reference for more information on the underlying behavior of these controls and indicators.
The Image Controls tab provides basic display controls for image cropping, image averaging, and OpenGL rendering and window behavior.
Control or Indicator Name | Associated Capture API Function and Arguments | Notes |
Request Mode |
| Also calls |
Average # |
| Averaging will not work in Force Trigger mode. |
JPEG Downsample x2 |
| Speeds up JPEG decompression by trading off image resolution. |
Start A-scan Offset |
| ​ |
Total A-scans |
| ​ |
axSetupDisplay |
| Initiates OpenGL rendering functionality. |
Polar Scan Convert |
| Supports display of OCT images catpured using a rotational scanning device. |
Interpolation |
| ​ |
Colormap |
| ​ |
Contrast, Brightness |
| ​ |
Window Size |
| ​ |
Crop Dimensions |
|
|
The Buffer tab provides an indication of the current Main Image Buffer status, an ability to Save and Load buffers to/from a file for offline storage and retrieval, and other status information related to session initialization.
Control or Indicator Name | Associated Capture API Function and Arguments | Notes |
Buffer Status |
| ​ |
LOAD |
| Status queried with immediate call to |
SAVE |
| Status queried with immediate call to |
CLEAR |
| ​ |
Scanner status: |
| Queried with immediate call to |
axStartSession status: |
| Queried with immediate call to |
Path to AxsunOCTCapture.dll library: | ​ | Library file which Image Capture Tool has loaded (debugging info). |
Axsun Technical Support personnel may request information from the Packet Details tab when troubleshooting or assisting with debugging efforts.
The Scanner tab provides controls for a connected NI USB-6211 multi-function I/O device, commonly used to generate a raster-scan waveform for a 2-axis galvo scanner.
Control Name | Associated Capture API Function and Arguments | Notes |
STOP SCAN |
| ​ |
1D LINE SCAN |
| ​ |
2D RASTER SCAN |
| ​ |
Scan Pattern |
|
|
Sample Clock |
| ​ |
Auto Restart | ​ | If ON, changes to the Scan Pattern control will immediately update the currently executing scan pattern. |
NOTE: The Scanner controls tab will be disabled if a compatible NI USB-6211 device was not connected and recognized during Image Capture Tool startup. Quit the Image Capture Tool, connect the device, and relaunch the Image Capture Tool to enable this tab.
The PCIe tab provides basic controls for DAQ Imaging Mode and low-level FPGA register R/W access when connected to a DAQ via the PCIe interface.
Control Name | Associated Capture API Function and Arguments | Notes |
PCIeDAQ: LIVE |
| ​ |
PCIeDAQ: OFF |
| ​ |
PCIeDAQ: RECORD |
|
|
WRITE (PCIe Registers) |
| |
READ (PCIe Registers) |
| Reads all registers in a loop and lists hex and decimal values in the associated table. (For Axsun internal use only.) |
WRITE (FPGA Registers) |
| |
READ (FPGA Registers) |
| Reads all registers in a loop and lists hex and decimal values in the associated table. |
Pipeline Mode |
| ​ |
NOTE: The PCIe controls tab will be disabled unless a PCIe capture session was successfully started by selecting the PCIe interface at Image Capture Tool startup (also seeaxStartSessionPCIe()
). The controls and associated API function calls on this tab are not operational when connected to a DAQ via the Ethernet or USB interfaces.
To exit the Image Capture Tool simply close the main window by clicking the "x" icon in the upper right corner.