measure.py

import typing
from plot import show_plot
from analyze import calc_stats, print_stats
from fileio import save_frame_times
import time
from camera_base import CameraBase
from create_camera import create_camera

WARMUP_FRAMES = 50
MEASURED_FRAMES = 1000


def get_current_time_ms() -> float:
    return time.time() * 1000


def warmup_camera(cam: CameraBase, frames: int) -> None:
    print(f"Skipping {frames} frames to warm up camera...")
    frames_received = 0
    while frames_received < frames:
        success, _ = cam.read_frame()
        if success:
            frames_received += 1


def measure_frame_times(cam: CameraBase, frames: int) -> typing.List[float]:
    print(f"Measuring timing of {frames} frames...")
    prev_time = get_current_time_ms()
    frame_times: typing.List[float] = []
    while len(frame_times) < frames:
        success, _ = cam.read_frame()
        if success:
            timestamp = get_current_time_ms()
            frame_times.append(timestamp - prev_time)
            prev_time = timestamp
    return frame_times


if __name__ == "__main__":
    with create_camera() as cam:
        warmup_camera(cam, WARMUP_FRAMES)
        capture_start = get_current_time_ms()
        frame_times = measure_frame_times(cam, MEASURED_FRAMES)
        capture_end = get_current_time_ms()

    stats = calc_stats(frame_times)
    print_stats(stats)
    save_frame_times(frame_times)
    show_plot(frame_times)  # This blocks until user closes plot window