`ultralytics 8.3.35` enable `auto` letterbox if model is `dynamic` (#17687)

Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

ultralytics/__init__.py

@@ -1,6 +1,6 @@
 # Ultralytics YOLO 🚀, AGPL-3.0 license
 
-__version__ = "8.3.34"
+__version__ = "8.3.35"
 
 import os
 

ultralytics/engine/predictor.py

@@ -153,7 +153,11 @@ class BasePredictor:
             (list): A list of transformed images.
         """
         same_shapes = len({x.shape for x in im}) == 1
-        letterbox = LetterBox(self.imgsz, auto=same_shapes and self.model.pt, stride=self.model.stride)
+        letterbox = LetterBox(
+            self.imgsz,
+            auto=same_shapes and (self.model.pt or getattr(self.model, "dynamic", False)),
+            stride=self.model.stride,
+        )
         return [letterbox(image=x) for x in im]
 
     def postprocess(self, preds, img, orig_imgs):