cell_loader_ctrl/playgrounds/datamatrix_playground.py

from picamera2 import Picamera2
import cv2
from pylibdmtx.pylibdmtx import decode

# Initialize camera
picam2 = Picamera2()
picam2.configure(picam2.create_preview_configuration(main={"format": "BGR888", "size": (640, 480)}))
picam2.start()

# Your configured ROI
x, y, w, h = 100, 0, 260, 450  # replace with your new values


print("Press Enter to capture and decode a frame. Ctrl+C to exit.")

while True:
    input("Capture frame now...")
    
    # Capture frame
    frame = picam2.capture_array()
    
    # Crop to ROI
    roi = frame[y:y+h, x:x+w]
    
    # Convert to grayscale + enhance contrast
    gray = cv2.cvtColor(roi, cv2.COLOR_BGR2GRAY)
    gray = cv2.equalizeHist(gray)
    
    # Optional: save the cropped ROI to check visually
    cv2.imwrite("roi_test.jpg", gray)
    
    # Decode DataMatrix
    decoded = decode(gray)
    
    if decoded:
        print("DataMatrix detected!")
        for d in decoded:
            print("Decoded content:", d.data.decode('utf-8'))
    else:
        print("No DataMatrix detected in this frame.")

picam2.stop()