Configure an Acquisition¶
This tutorial will provide an in-depth explanation of setting configuration properites and demonstrate the relationships between various Acquire classes, such as CameraProperties and StorageProperties, used in the configuration process. In this example, we'll only configure one video source.
Initialize Runtime¶
Runtime is the main entry point in Acquire. Through the runtime, you configure your devices, start acquisition, check acquisition status, inspect data as it streams from your cameras, and terminate acquisition. The device_manager method in Runtime creates an instance of the DeviceManager class. The get_configuration method in Runtime creates an instance of the Properties class. To configure the acquisition, we'll use those two methods to grab the configuration and to initialize a DeviceManager object to set the attributes of Properties and related classes.
import acquire
# Initialize a Runtime object
runtime = acquire.Runtime()
# Initialize the device manager
dm = runtime.device_manager()
# Grab the current configuration
config = runtime.get_configuration()
Utilize DeviceManager¶
DeviceManager contains a devices method which creates a list of DeviceIdentifier objects each representing a discovered camera or storage device. Each DeviceIdentifier has an attribute kind that is a DeviceKind object, which has attributes specifying whether the device is a camera or storage device, as well as Signals and StageAxes attributes. The Signals and StageAxes attributes would apply to device kinds such as stages, which are not yet supported by Acquire.
DeviceManager has 2 methods for selecting devices for the camera and storage. For more information on these methods, check out the Device Selection tutorial. We'll use the select method in this example to choose a specific device for the camera and storage.
# Select the radial sine simulated camera as the video source
config.video[0].camera.identifier = dm.select(acquire.DeviceKind.Camera, "simulated: radial sin")
# Set the storage to Tiff
config.video[0].storage.identifier = dm.select(acquire.DeviceKind.Storage, "Tiff")
Properties Class Explanation¶
Using Runtime's get_configuration method we created config, an instance of the Properties class. Properties contains only one attribute video which is a tuple of VideoStream objects since Acquire currently supports 2 camera streaming. To configure the first video stream, we'll index this tuple to select the first VideoStream object config.video[0].
VideoStream objects have 2 attributes camera and storage which are instances of the Camera and Storage classes, respectively, and will be used to set the attributes of the selected camera device simulated: radial sin and storage device Tiff. The other attributes of VideoStream are integers that specify the maximum number of frames to collect and how many frames to average, if any, before storing the data. The frame_average_count has a default value of 0, which disables this feature. We'll specify the max frame count, but keep the frame averaging disabled with:
Configure Camera¶
Camera class objects have 2 attributes, settings, a CameraProperties object, and an optional attribute identifier, which is a DeviceIdentifier object.
CameraProperties has 5 attributes that are numbers and specify the exposure time and line interval in microseconds, how many pixels, if any, to bin (set to 1 by default to disable), and tuples for the image size and location on the camera chip. The other attributes are all instances of different classes. The pixel_type attribute is a SampleType object which indicates the data type of the pixel values in the image, such as Uint8. The readout_direction attribute is a Direction object specifying whether the data is read forwards or backwards from the camera. The input_triggers attribute is an InputTriggers object that details the characteristics of any input triggers in the system. The output_triggers attribute is an OutputTriggers object that details the characteristics of any output triggers in the system. All of the attributes of InputTriggers and OutputTriggers objects are instances of the Trigger class. The Trigger class is described in Triggers from a JSON file.
We'll configure some camera settings below.
# Set the time for collecting data for a each frame
config.video[0].camera.settings.exposure_time_us = 5e4 # 50 ms
# (x, y) size of the image in pixels
config.video[0].camera.settings.shape = (1024, 768)
# Specify the pixel type as uint16
config.video[0].camera.settings.pixel_type = acquire.SampleType.U16
Configure Storage¶
Storage objects have 2 attributes, settings, a StorageProperties object, and an optional attribute identifier, which is an instance of the DeviceIdentifier class described above.
StorageProperties has 2 attributes external_metadata_json and filename which are strings of the filename or filetree of the output metadata in JSON format and image data in whatever format corresponds to the selected storage device, respectively. first_frame_id is an integer ID that corresponds to the first frame of the current acquisition and is typically 0. pixel_scale_um is the camera pixel size in microns. acquisition_dimensions is a list of StorageDimension, one for each acquisition dimension, ordered from fastest changing to slowest changing. enable_multiscale is a boolean used to specify if the data should be saved as an image pyramid.
We'll specify the name of the output image file below.
Update Configuration Settings¶
None of the configuration settings are updated in Runtime until the set_configuration method is called. We'll be creating a new Properties object with the set_configuration method. For simplicity, we'll reuse config for the name of that object as well, but note that new_config = runtime.set_configuration(config) also works here.