Aravis-detector

This section only covers instructions specific to the Aravis-Detector plugin. For a general overview of Odin Data frameProcessor plugins please refer to the user and developer guides from the odin documentation.

Plugin Setup

The Aravis-detector should be loaded first in the FrameProcessor plugin chain. It doesn’t require the use of the frame receiver app as it directly handles buffers from the aravis camera. To load the plugin you can use the following json command:

{   "plugin": {
    "load": {
        "index": "aravis",
        "name": "AravisDetectorPlugin",
        "library": "<Prefix Directory>/lib/libAravisDetectorPlugin.so"
}}}

Note

Here, index refers to the plugin alias for the frame processor and can be treated as a variable name. It will later be used to target the plugin when providing the frame processor with configuration values. The name field must be the same value as the main file name and library field should provide the frame processor with a complete path to the file installed.If you followed the build instructions you should find this in …./odin_camera_driver/prefix/libraries/.

The rest of the plugins can then be connected to the aravis-detector. Odin allows plugins to be connected in a tree structure, where plugins can be chained one to another or multiple plugins can be connected into one. For the default aravis plugin config file the live view and hdf plugins are both directly connected to it, similar to plugins 1 and 3 in the following example:

{   "plugin": {
        "connect": {
            "index": "<other plugin 1>",
            "connection": "aravis"
}},
    "plugin": {
        "connect": {
            "index": "<other plugin 2>",
            "connection": "<other plugin 1>"
}},
    "plugin": {
        "connect": {
            "index": "<other plugin 3>",
            "connection": "<aravis>"
}}}

Plugin Configurations

Different configurations can be passed at start up using the same config file from the setup process. The syntax used is:

{ "aravis":{
        "list_devices": true,
        "compression": "none",
        "dataset": "data",
        "ip_address": "169.254.186.47"
}}

The following list is a complete set of available plugin configuration and their aliases:

Config	Description	Default value
ip_address	Connects to the camera with the specified IP address	127.0.0.1
exposure_time	Sets the exposure time to the given value in microseconds	1000.0
frame_rate	Sets the frame rate to the given value in Hz	5
frame_count	Sets a limit to the number of buffers acquired in continuos mode. 0 for no limit	0
pixel_format	Sets the pixel format used by the camera	Mono8
acquisition_mode	Sets the camera’s acquisition mode. Not fully implemented	Continuous
aravis_callback	When set to true the camera sends signals when an mage buffers is finished. When set to false the plugin checks for buffers on a regular interval	True
data_set_name	name of the data set all frames are assigned to	No default
file_name	name of the file name all frames are assigned to	No default
compression	compression method used	No default
file_path	file path for all temporary files. Currently used by genicam	No default
start	start camera acquisition of buffers	value is ignored
stop	stop camera acquisition of buffers	value is ignored
list_devices	lists all genicam devices connected	value is ignored
frames	specifies a number of frames to acquire	deprecated, no default

Note

The recommended way to change plugin configuration is through the use of the odin-control server.

Supported genicam features

The following features are implemented in the Aravis Plugin:

Feature	Plugin support	API implementation	Notes
connecting to cameras	Can detect connected cameras and connect using the ip address	Only displays the model name of the camera
Acquisition modes	Only Continuous mode is implemented at the moment	Uses continuous mode only	The number of buffers acquired can be limited through the use of the variable frame_count (Number of frames, on the web GUI). Note: this value sounds similar to the frame_count function in Aravis which sets the number of frames in MultiFrame mode. This is not implemented in the plugin.
Frame rate	Can be set and read	Can be controlled through both the web GUI and arvcli	The plugin will not allow the user to set the frame rate above the hardware limit..
Exposure time	Can be set and read	Can be controlled through both the web GUI and arvcli	Similar to frame rate, the plugin will keep the exposure time within hardware bounds specified in the genicam xml file
Pixel format	Currently the software can read available formats and change them.	Not yet fully implemented	Some formats are not supported because they require further processing (Mono12)
Resolution	Can be read	Is not displayed in the gui but it can be requested through the cli	Resolution can only be changed through AOI/ROI or Binning which are not yet implemented
XML readout	Automatically saves the XML file when connecting to camera	n/a	This feature is mostly useful for trouble shooting. Saves the xml file in the specified temporary folder

Potential Features

The Aravis library already implements a large set of GenICam features. The following is a list of features that might get added in the future:

1. Binning/Decimation - groups pixels together to reduce the resolution of the image

2. ROI/AOI - scan the sensor in a limited region of interest of nxn pixels.

3. Trigger modes - change between software/ self/ external trigger.

4. Burst mode - saves images internally, allowing for a faster frame rate over a short period.

5. Offset - sensor signal cutoff value used to remove noise.

6. Read out control - changes the delay between frame capture and transfer.