Fix missing batch dimension.

app.py

@@ -75,8 +75,10 @@ def run_inference(pil_image: Image.Image) -> np.ndarray:
     """
     input_tensor = preprocess_image(pil_image)
     input_name = session.get_inputs()[0].name
+    # Expand dimensions to make it (1, C, H, W)
+    input_tensor_expanded = np.expand_dims(input_tensor, axis=0)
     # Only refined_logits are used (initial_logits is ignored)
-    _, refined_logits = session.run(None, {input_name: input_tensor})
+    _, refined_logits = session.run(None, {input_name: input_tensor_expanded})
     return refined_logits[0]
 
 def get_tags(refined_logits: np.ndarray, metadata: dict, default_threshold: float):