Properties from a JSON file¶
This tutorial will provide an example of saving and subsequently loading a Properties object from a JSON file.
Initialize Runtime¶
To start, we'll import Acquire and create a Runtime object, which coordinates the streaming process.
Configure Camera¶
All camera settings are captured by an instance of the Properties class, which will be associated with a given camera acquisition.
You can update any of the settings in this instance of Properties. To save any updated settings, use the set_configuration method. For this tutorial, we'll simply specify a camera, and then save these new settings. Note that more settings must be provided before this Properties object could be used for an acquistion. Check out Configure an Acquisition for more information on configuring an acquisition.
# set the radial sine simulated camera as the first video stream
config.video[0].camera.identifier = runtime.device_manager().select(acquire.DeviceKind.Camera, "simulated: radial sin")
# save the updated settings
config = runtime.set_configuration(config)
Save Properties to a JSON file¶
We'll utilize the json library to write our properties to a JSON file to save for subsequent acquisition.
import json
# cast the properties to a dictionary
config = config.dict()
# convert the dictionary to json with "human-readable" formatting
config = json.dumps(config, indent=4, sort_keys=True)
# save the properties to file "sample_props.json" in the current directory
with open("sample_props.json", "w") as outfile:
outfile.write(config)
Example JSON file¶
The resulting sample_props.json file is below:
{
"video": [
{
"camera": {
"identifier": {
"id": [
0,
1
],
"kind": "Camera",
"name": "simulated: radial sin"
},
"settings": {
"binning": 1,
"exposure_time_us": 0.0,
"input_triggers": {
"acquisition_start": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
},
"exposure": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
},
"frame_start": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
}
},
"line_interval_us": 0.0,
"offset": [
0,
0
],
"output_triggers": {
"exposure": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
},
"frame_start": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
},
"trigger_wait": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
}
},
"pixel_type": "U16",
"readout_direction": "Forward",
"shape": [
1,
1
]
}
},
"frame_average_count": 0,
"max_frame_count": 18446744073709551615,
"storage": {
"identifier": {
"id": [
0,
5
],
"kind": "Storage",
"name": "trash"
},
"settings": {
"acquisition_dimensions": [],
"enable_multiscale": false,
"external_metadata_json": "",
"filename": "",
"first_frame_id": 0,
"pixel_scale_um": [
0.0,
0.0
]
},
"write_delay_ms": 0.0
}
},
{
"camera": {
"identifier": {
"id": [
0,
0
],
"kind": "NONE",
"name": ""
},
"settings": {
"binning": 1,
"exposure_time_us": 0.0,
"input_triggers": {
"acquisition_start": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
},
"exposure": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
},
"frame_start": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
}
},
"line_interval_us": 0.0,
"offset": [
0,
0
],
"output_triggers": {
"exposure": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
},
"frame_start": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
},
"trigger_wait": {
"edge": "Rising",
"enable": false,
"kind": "Input",
"line": 0
}
},
"pixel_type": "U16",
"readout_direction": "Forward",
"shape": [
0,
0
]
}
},
"frame_average_count": 0,
"max_frame_count": 18446744073709551615,
"storage": {
"identifier": {
"id": [
0,
0
],
"kind": "NONE",
"name": ""
},
"settings": {
"acquisition_dimensions": [],
"enable_multiscale": false,
"external_metadata_json": "",
"filename": "",
"first_frame_id": 0,
"pixel_scale_um": [
0.0,
0.0
]
},
"write_delay_ms": 0.0
}
}
]
}
Load Properties from a JSON file¶
You can load the settings in the JSON file to a Properties object and set this configuration for your Runtime as shown below:
import acquire
import json
# create a Runtime object
runtime = acquire.Runtime()
# Instantiate a `Properties` object from the settings in sample_props.json
config = acquire.Properties(**json.load(open('sample_props.json')))
# save the properties for this instance of Runtime
config = runtime.set_configuration(config)