C4 W3 Bounding Box Predictions - wrong assignments to bh and bw?

[Mun_Chung_Wong]

{Moved to and created this new thread by @rmwkwok)

Actually, I believe there is another mistake in video 5 titled “Bounding Box Predictions”.

From around 11:28 Andrew calculates value of 0.9 referring to the green horizontal line width of
red bound box relative to blue grid cell width. However, he goes on to assign 0.9 to bh the red
bounding box height output.

Similarly, 0.5 being the relative ratio of bounding box height to grid cell heigh is assigned to
bounding box width bw output.

The above are also captured in lecture notes slide 18.

Please kindly double check if I haven’t misunderstood the calculations.

Thanks,
MCW

[rmwkwok]

Hello @Mun_Chung_Wong,

So, just to be clear, are you saying that 0.9 should have been assigned to bw, and 0.5 to bh? Or is there anything else?

Cheers,
Raymond

[Mun_Chung_Wong]

Ah yeah what I meant to ask is shouldn’t 0.9 be assigned to bh, and 0.5 to bw?

Thanks,
MCW

[rmwkwok]

Oh yes! I found the definition for bw and bh, and they are as expected: (I know sometimes I can be wasting time being too careful , but it is still good to be careful and check any symbol’s definition )

So, I think you are right, and they were swapped. I will report this and see if the staff or other mentors have anything to say about this.

Thank you @Mun_Chung_Wong

Cheers,
Raymond