Data capture context
====================

The context handles incoming eye tracker data before to pass them to a processing pipeline.

## live_streaming_context.json

For this use case we need to connect to a Tobii Pro Glasses 2 device: **ArGaze** provides a [ready-made context](../../user_guide/eye_tracking_context/context_modules/tobii_pro_glasses_2.md) class to capture data from this device.

While *address*, *project*, *participant* and *configuration* entries are specific to the [TobiiProGlasses2.LiveStream](../../argaze.md/#argaze.utils.contexts.TobiiProGlasses2.LiveStream) class, *name*, *pipeline* and *observers* entries are part of the parent [ArContext](../../argaze.md/#argaze.ArFeatures.ArContext) class.

```json
{
	"argaze.utils.contexts.TobiiProGlasses2.LiveStream": {
		"name": "Tobii Pro Glasses 2 live stream",
		"address": "10.34.0.17",
		"project": "HAIKU-XP",
		"participant": "Pilot-A",
		"configuration": {
			"sys_ec_preset": "Indoor",
			"sys_sc_width": 1920,
			"sys_sc_height": 1080,
			"sys_sc_fps": 25,
			"sys_sc_preset": "Auto",
			"sys_et_freq": 50,
			"sys_mems_freq": 100
		},
		"pipeline": "live_processing_pipeline.json",
		"observers": {
			"observers.IvyBus": {
				"name": "argaze_haiku",
				"bus": "10.34.127.255:2023"
			}
		}
	}
}
```

The [live_processing_pipeline.json](pipeline.md) file mentioned above is described in the next chapter.

The *IvyBus* observer object is defined into the [observers.py](observers.md) file that is described in a next chapter.