Why the decrementation of bounding box coordinate values when ingesting PASCAL VOC?

[monocongo]

When the VOCIngestor._get_detection function parses bounding box coordinate values it decrements the values. Why is this so?

For example, if my image is 200 pixels wide and contains a box that's full width with xmin==0 and xmax==199 then this code results in a detection with left==-1 and right==198. Is this really what we want? It gives me trouble in this situation, in that it results in invalid boxes since -1 is out-of-range.

Also the box coordinate decrementations result in the box being pushed to the left/top by one pixel in every case. Is this really what we want? Perhaps there was some justification for the decrementations when the code was written that's just not obvious to me?

[ecarrenolozano]

I notice the same, this is one example:
KITTI (original)
Pedestrian 0.00 0 0.33 352.66 168.09 381.95 252.38 1.72 0.74 0.56 -5.14 1.63 15.13 0.01
PASCAL VOC
<object> <name>Pedestrian</name> <difficult>0</difficult> <occluded>0</occluded> <truncated>0</truncated> <pose>Unspecified</pose> <bndbox> <xmin>353.66</xmin> <xmax>382.95</xmax> <ymin>169.09</ymin> <ymax>253.38</ymax> </bndbox> </object>

Is this a normal behavior?