[Fix] Minor adjustments (#241)

* Fix an old bug in box_np_ops, not used or influencing results

* Update a minor filter criterion in KITTI evaluation

* Update the fixed criterion, not influencing KITTI results

mmdet3d/core/bbox/box_np_ops.py

@@ -347,7 +347,7 @@ def points_cam2img(points_3d, proj_mat):
     """
     points_shape = list(points_3d.shape)
     points_shape[-1] = 1
-    points_4 = np.concatenate([points_3d, np.zeros(points_shape)], axis=-1)
+    points_4 = np.concatenate([points_3d, np.ones(points_shape)], axis=-1)
     point_2d = points_4 @ proj_mat.T
     point_2d_res = point_2d[..., :2] / point_2d[..., 2:3]
     return point_2d_res

mmdet3d/datasets/kitti_dataset.py

@@ -642,10 +642,9 @@ class KittiDataset(Custom3DDataset):
         # Post-processing
         # check box_preds_camera
         image_shape = box_preds.tensor.new_tensor(img_shape)
-        valid_cam_inds = ((box_preds_camera.tensor[:, 0] < image_shape[1]) &
-                          (box_preds_camera.tensor[:, 1] < image_shape[0]) &
-                          (box_preds_camera.tensor[:, 2] > 0) &
-                          (box_preds_camera.tensor[:, 3] > 0))
+        valid_cam_inds = ((box_2d_preds[:, 0] < image_shape[1]) &
+                          (box_2d_preds[:, 1] < image_shape[0]) &
+                          (box_2d_preds[:, 2] > 0) & (box_2d_preds[:, 3] > 0))
         # check box_preds
         limit_range = box_preds.tensor.new_tensor(self.pcd_limit_range)
         valid_pcd_inds = ((box_preds.center > limit_range[:3]) &