Table 2.

Input and output of each hourglass

Hourglass	Input	Output	After scale up	After scale down
Hourglass 1	32 * 32 * 128	32 * 32 * 128	64 * 64 * 128	_
Hourglass 2	64 * 64 * 128	64 * 64 * 128	_	32 * 32 * 128
Hourglass 3	32 * 32 * 128	32 * 32 * 128	_	–

“_” indicates the corresponding operation has not been done