added checkpoint

app.py

@@ -1,3 +1,15 @@
+import os
+import subprocess
+
+# --- Ensure SAM checkpoint is present ---
+SAM_CHECKPOINT = "sam_vit_h_4b8939.pth"
+if not os.path.exists(SAM_CHECKPOINT):
+    print("Downloading SAM checkpoint...")
+    subprocess.run([
+        "wget",
+        "https://dl.fbaipublicfiles.com/segment_anything/sam_vit_h_4b8939.pth"
+    ])
+# ----------------------------------------
 import gradio as gr
 import numpy as np
 from PIL import Image