# filters.py
import base64
from flask import current_app
import cv2

def to_base64(image_np):
    # Convert numpy array to PNG image in memory
    _, img_encoded = cv2.imencode('.png', image_np)
    img_base64 = base64.b64encode(img_encoded).decode('utf-8')
    return img_base64

def init_app(app):
    app.jinja_env.filters['to_base64'] = to_base64