[Python] Create glowing edges Photoshop filter using open-cv

Does anyone know how to recreate the Photoshop filter called Glowing Edges using python/open-cv? This should be a bunch of filters one after another, maybe someone already made it.

I have tried to recreate the same filter and it looks like below, but still too noisy and the result is similar, but not as it is in photoshop: on the left is what I expected to get (Photoshop glowing edges filter with settings: edge width 4, brightness 4, smoothness 15) and on the right is what I could reconstruct in my filter. The Photoshop filter lines look smooth and solid, while mine are noisy and the overall image has too much dotted noise.



import sys
from PyQt6.QtWidgets import (
QApplication, QMainWindow, QLabel, QPushButton,
QVBoxLayout, QFileDialog, QWidget
)
from PyQt6.QtGui import QPixmap, QImage
from PyQt6.QtCore import Qt
from PIL import Image
import cv2
import numpy as np


class EdgeFilter(QMainWindow):
def __init__(self):
super().__init__()
self.setWindowTitle("Filter")
self.setGeometry(100, 100, 600, 400)
self.original_image = None
self.filtered_image = None
self.init_ui()

def init_ui(self):
central_widget = QWidget()
self.setCentralWidget(central_widget)
layout = QVBoxLayout(central_widget)
self.btn_open = QPushButton("Open img")
self.btn_open.clicked.connect(self.open_image)
layout.addWidget(self.btn_open)
self.filtered_label = QLabel("Filter")
self.filtered_label.setAlignment(Qt.AlignmentFlag.AlignCenter)
self.filtered_label.setMinimumSize(400, 300)
self.filtered_label.setStyleSheet("border: 1px solid gray;")
layout.addWidget(self.filtered_label)

############## FILTER DOWN HERE \/ \/ \/ \/ \/ #####################
def apply_filter(self):
img = self._ensure_gray_numpy(self.original_image)

scales = [2.0, 3.0, 4.0]
edges = np.zeros_like(img, dtype=np.float64)

for scale in scales:
size = int(12 * scale + 1)
if size % 2 == 0: size += 1
blur = cv2.GaussianBlur(img, (size, size), scale)

gx = cv2.Sobel(blur, cv2.CV_64F, 1, 0, ksize=3)
gy = cv2.Sobel(blur, cv2.CV_64F, 0, 1, ksize=3)
mag = np.sqrt(gx ** 2 + gy ** 2)
edges = np.maximum(edges, mag)

edges = np.where(edges > edges.mean() * 1.7, 200, 0)

self.filtered_image = Image.fromarray(edges.astype(np.uint8))
self.display_image(self.filtered_image)

def open_image(self):
file_path, _ = QFileDialog.getOpenFileName(
self, "Open img", "", "Images (*.png *.jpg *.jpeg)"
)
if file_path:
self.original_image = Image.open(file_path).convert('L')
self.apply_filter()

def _ensure_gray_numpy(self, image):
if image is None:
return np.zeros((1, 1), dtype=np.uint8)
if isinstance(image, np.ndarray):
arr = image
if arr.ndim == 3:
try:
arr = cv2.cvtColor(arr, cv2.COLOR_RGB2GRAY)
except Exception:
try:
arr = cv2.cvtColor(arr, cv2.COLOR_BGR2GRAY)
except Exception:
arr = np.mean(arr, axis=2).astype(np.uint8)
return arr.astype(np.uint8)

pil = image
if pil.mode != "L":
pil = pil.convert("L")
return np.array(pil, dtype=np.uint8)

def display_image(self, image):
if image is None:
self.filtered_label.clear()
return
mode = image.mode
w, h = image.width, image.height
if mode == "L":
data = image.tobytes()
bytes_per_line = w
qimg = QImage(data, w, h, bytes_per_line, QImage.Format.Format_Grayscale8)
else:
pil_L = image.convert("L")
data = pil_L.tobytes()
bytes_per_line = w
qimg = QImage(data, w, h, bytes_per_line, QImage.Format.Format_Grayscale8)

pixmap = QPixmap.fromImage(qimg)
scaled_pixmap = pixmap.scaled(
self.filtered_label.size(),
Qt.AspectRatioMode.KeepAspectRatio,
Qt.TransformationMode.SmoothTransformation
)
self.filtered_label.setPixmap(scaled_pixmap)

if __name__ == '__main__':
app = QApplication(sys.argv)
window = EdgeFilter()
window.show()
sys.exit(app.exec())

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