Files
entropy/entropy.py
T
2026-03-12 10:25:06 +00:00

56 lines
2.1 KiB
Python

#!/usr/bin/env python3
import cv2
import hashlib
import secrets
import time
import argparse
def fetch_frame_opencv(url):
cap = cv2.VideoCapture(url)
ret, frame = cap.read()
cap.release()
if not ret:
raise ValueError("Failed to fetch frame.")
return frame
def generate_random_numbers(frame, bit_lengths):
_, img_encoded = cv2.imencode('.jpg', frame)
img_bytes = img_encoded.tobytes()
entropy = hashlib.sha256(img_bytes).digest()
return {length: secrets.randbits(length) for length in bit_lengths}
def main():
parser = argparse.ArgumentParser(description="Generate random numbers from camera entropy.")
parser.add_argument("--url", default="http://192.168.0.200/mjpg/video.mjpg", help="Camera MJPEG stream URL")
parser.add_argument("--single", type=int, default=1, help="Generate N random numbers and exit (default: 1)")
parser.add_argument("--bit", type=int, default=256, help="Bit length of each random number (default: 256)")
parser.add_argument("--loop", action="store_true", help="Run forever, generating numbers every second")
args = parser.parse_args()
if args.loop:
while True:
try:
frame = fetch_frame_opencv(args.url)
random_numbers = generate_random_numbers(frame, [args.bit])
for number in random_numbers.values():
print(f"{number:x}")
except Exception as e:
print(f"Error: {e}", file=sys.stderr)
time.sleep(1) # Wait before retrying
else:
for i in range(args.single):
try:
frame = fetch_frame_opencv(args.url)
random_numbers = generate_random_numbers(frame, [args.bit])
for number in random_numbers.values():
print(f"{number:x}")
except Exception as e:
print(f"Error: {e}", file=sys.stderr)
return 1
if args.single > 1 and i < args.single - 1:
time.sleep(1) # Small delay between frames
if __name__ == "__main__":
import sys
main()