Much larger distance Error compared to paper

[jkstyle2]

Thanks for the great work @cersar , it's been so helpful to understand the principle of 3d vision processing. While I've been working on with your project, I've noticed that the 3D Location error is much larger than the paper shows. x and y distance errors are relatively fine, but the z coordinate error(forward direction) is quite different from the original paper. In the paper, it shows that there are about 1m error in 10-20m distance and 2m error in 20-30m, but I usually get between 2m - 10m error from your code.

The result of Paper:

The result of mine:

file:  000127.png
box_2D:  [591.44 175.51 657.28 239.12]
center:  [ 0.27  1.18 15.25]
center_gt:  [ 0.38  1.7  20.03]
dimensions:  [1.02 1.47 2.6 ]
dimensions_gt:  [1.61 1.66 3.2 ]

Can you figure it out and work out this issue?

Overall, the orientation and dimension estimations seem great, and also 3D -> 2D projection seems great in the image, but when I try checking it in bird's eye view which includes the distance information, I see huge error between ground truth and the estimation value.