This slide is expolanation about OpenPose Model which realtime recognise poses of multiple people.

1. OpenPose
Realtime Multi-Person 2D Pose Estimation using Part Anity Fileds
By Zhe Cao @The Robotics Institute CMU
mabonki0725
()11
June 30, 2017

2. Real Time
2017/04/14 https://arxiv.org/abs/1611.08050
OpenPose GitHub
PBL@AIIT openPose
OpenPose
Real Time 20Frame/sec)
Figure: OpenPose
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3. OpenPose
Real Time
Top-down ottom-up
Top-down
OpenPose Bottom-up
?
! @
A
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4. OpenPose
Real Time
Bottom-up
( CNN
F CNN S1
F CNN L1
! T
F St−1 Lt−1 CNN St
F St−1 Lt−1 CNN Lt
PAF )
Figure: CNN
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5. CNN
CNN
ft
S =
J
j=1 p
W(p)||St
j(p) − S∗
j (p)||2
2
ft
L =
J
j=1 p
W(p)||Lt
j(p) − L∗
j (p)||2
2
L =
T
t=1
ft
S + ft
L !
j P
St
j t j
Lt
j t j
S∗
j j
L∗
j j
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6. CNN
j
S∗
j,k = exp −
||P − xj,k||2
2
σ2
S∗
j = max
k
S∗
j,k(P) #
k k xj,k k j σ
Figure: )
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7. PAF(Partial Anity Filed) Ec
vk =
xj2,k − xj1,k
||xj2,k − xj1,k||2
$
L∗
c,k(p) = vk
vk vk⊥|p − xj1,k| σl
0 (otherwise)
%
L∗
c (p) =
1
nc(p) k
L∗
c,k(p)
Ec =
u=1
u=0
Lc(p(u))
dj2 − dj1
||dj2 − dj1 ||2
du '
k k xj,k k j c
Figure: PAF 7 / 10

8. PAF(Partial Anity Filed) 2
z
max
z
Ec = max
Zc
m∈Dj1
n∈Dj2
Emnzmn
j1,j2
s.t
n∈Dj2
zm,n
j1,j2
≤ 1
m∈Dj1
zm,n
j1,j2
≤ 1
Ec zm,n
j1,j2
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9. PAF(Partial Anity Filed) n 2
n 2 NP Hard
?
! @
A
Figure: n
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10. OpenPose Realtime
Figure:
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