def connect_device(self):
"""
:return:
"""
num_channels = get_num_channels(self.device_name, 'eeg')
self.device = OpenBCIBoard(port=self.device_port,
num_channels=num_channels)
def setup(self):
"""
Generic setup for any analysis module, can be overriden by implementing in any child class
This sets up subscriber and publisher based on input and output feature names
"""
# usually this module is used with incoming EEG,
# so we'd like to know num channels, and a header is for convenience
# hard-coded "eeg" could be a problem if the device's metric name for raw data is not "eeg"
# currently "eeg" is a known good metric name for both OpenBCI and Muse
if "num_channels" in self.module_settings:
# module specific setting
self.num_channels = self.module_settings["num_channels"]
elif "num_channels" in self.global_settings:
#global setting
self.num_channels = self.global_settings["num_channels"]
else:
# default for the device type
self.num_channels = get_num_channels(self.device_name,"eeg")
self.headers = ['timestamp'] + ['channel_%s' % i for i in xrange(self.num_channels)]
# if input, instantiate subscriber
if len(self.inputs):
# there is only one subscriber to handle all inputs
self.subscriber = PikaSubscriber(device_name=self.device_name,
device_id=self.device_id,
rabbitmq_address=self.rabbitmq_address,
metrics=self.inputs)
# if output, instantiate publishers
if len(self.outputs):
for output_key, output in self.outputs.iteritems():
# each output has a specific key, assign a placeholder for it in publishers collection
self.publishers[output_key] = {}
self.output_buffers[output_key] = {}
# each output has a parameter called "message_queues"
# this can be a single value or a list, i.e. "foo" or ["foo1","foo2"]
# most of the time, this will be a single string
# an example of where an output might use more than one message_queue might be:
# one output goes to visualization, while a second copy continues down the processing chain
if 'message_queues' in output:
# for convenience, convert the "message_queues" parameter to list if it isn't already
if type(output['message_queues']) != list:
output['message_queues'] = [output['message_queues']]
# there is one publisher per output
for message_queue_name in output['message_queues']:
self.publishers[output_key][message_queue_name] = PikaPublisher(
device_name=self.device_name,
device_id=self.device_id,
rabbitmq_address=self.rabbitmq_address,
metric_name=message_queue_name)
# also instantiate an output buffer for each publisher
self.output_buffers[output_key][message_queue_name] = []
def start(self):
# callback functions to handle the sample for that metric (each metric has a specific number of channels)
cb_functions = {
metric:
self.callback_factory(metric,
get_num_channels(self.device_name, metric))
for metric in self.metrics
}
self.device.start(cb_functions)