Check conf_thres and iou_thres prior to use (#10515)

* Checks conf_thres and iou_thres at beign

Why checks conf_thres after operation with it?

Signed-off-by: Yonghye Kwon <developer.0hye@gmail.com>

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Update general.py

Signed-off-by: Yonghye Kwon <developer.0hye@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Glenn Jocher <glenn.jocher@ultralytics.com>

utils/general.py

@@ -898,6 +898,9 @@ def non_max_suppression(
          list of detections, on (n,6) tensor per image [xyxy, conf, cls]
     """
 
+    # Checks
+    assert 0 <= conf_thres <= 1, f'Invalid Confidence threshold {conf_thres}, valid values are between 0.0 and 1.0'
+    assert 0 <= iou_thres <= 1, f'Invalid IoU {iou_thres}, valid values are between 0.0 and 1.0'
     if isinstance(prediction, (list, tuple)):  # YOLOv5 model in validation model, output = (inference_out, loss_out)
         prediction = prediction[0]  # select only inference output
 
@@ -909,10 +912,6 @@ def non_max_suppression(
     nc = prediction.shape[2] - nm - 5  # number of classes
     xc = prediction[..., 4] > conf_thres  # candidates
 
-    # Checks
-    assert 0 <= conf_thres <= 1, f'Invalid Confidence threshold {conf_thres}, valid values are between 0.0 and 1.0'
-    assert 0 <= iou_thres <= 1, f'Invalid IoU {iou_thres}, valid values are between 0.0 and 1.0'
-
     # Settings
     # min_wh = 2  # (pixels) minimum box width and height
     max_wh = 7680  # (pixels) maximum box width and height