Screen Latency Demo

Setup

import aopy
import os
import numpy as np
from scipy import signal
import matplotlib.pyplot as plt
from datetime import date
from db import dbfunctions as db

blocks = [2621, 2622, 2623] #Block IDs to test
data_dir = "/data/raw" # Directory of raw data to load
pulses2avg = [2,10,10] # Number of pulses to average to calculate latency for each block.

Load data and calculate latency for each block

# These methods are out of date
for iblock, blockid in enumerate(blocks):
    files = aopy.data.get_filenames_in_dir(data_dir, blockid)
    print('Files in data_dir: ', files)
    data, metadata = aopy.preproc.parse_bmi3d(data_dir, files)

    # Clock timing
    clock_onsets = data['sync_clock']['timestamp']
    clock_timestamps, clock_values = aopy.preproc.get_edges_from_onsets(clock_onsets, 0.003)

    # Screen timing
    screen_values = data['measure_clock_offline']['value']
    screen_timestamps = data['measure_clock_offline']['timestamp']

    # Prepare data for plotting
    events = [clock_values, screen_values]
    timestamps = [clock_timestamps, screen_timestamps]
    labels= ['clock', 'screen']

    # Plot clock timing and screen timing
    pulse_time_start = clock_onsets[2]
    aopy.visualization.plot_events_time(events, timestamps, labels)
    plt.title('Sync State FPS: '+str(metadata['sync_state_fps']), fontsize=16)
    plt.xlim((pulse_time_start-0.05, pulse_time_start+.05))
    plt.show()

    # Calculate latency
    latency = np.empty(pulses2avg[iblock])
    latency[:] = np.nan

    for ipulse in range(pulses2avg[iblock]):
        clock_time = clock_onsets[ipulse*2]
        screen_time,_ = aopy.preproc.get_closest_value(clock_time, screen_timestamps[screen_timestamps>clock_time], radius=1)
        latency[ipulse] = screen_time - clock_time


    print('Block:', blockid, ' Average Latency ', np.round(1000*np.nanmean(latency),5), 'ms')

    print('\n')

Files in data_dir:  {'hdf': 'hdf/test20210827_11_te2621.hdf', 'ecube': 'ecube/2021-08-27_BMI3D_te2621'}
Warning: this bmi3d sync version is untested!
Sync latency estimate: 0.0231 s
Warning: last event (255) doesn't match bmi3d records (17)

Block: 2621  Average Latency  38.2 ms


Files in data_dir:  {'hdf': 'hdf/test20210827_12_te2622.hdf', 'ecube': 'ecube/2021-08-27_BMI3D_te2622'}
Warning: this bmi3d sync version is untested!
Sync latency estimate: 0.0047 s
Warning: last event (255) doesn't match bmi3d records (17)

Block: 2622  Average Latency  32.256 ms


Files in data_dir:  {'hdf': 'hdf/test20210827_13_te2623.hdf', 'ecube': 'ecube/2021-08-27_BMI3D_te2623'}
Warning: this bmi3d sync version is untested!
Sync latency estimate: 0.0256 s
Warning: last event (255) doesn't match bmi3d records (17)

Block: 2623  Average Latency  34.012 ms