3D-Assisted Image Feature Synthesis for Novel Views of an Object
Hao Su* Fan Wang* Li Yi Leonidas Guibas
* Equal contribution
3D-Assisted Image Feature Synthesis for Novel Views of an Object - - PowerPoint PPT Presentation
3D-Assisted Image Feature Synthesis for Novel Views of an Object Hao Su* Fan Wang* Li Yi Leonidas Guibas * Equal contribution View-agnostic Image Retrieval Retrieval using AlexNet features Query Cross-view Image Comparison Cross-view
Hao Su* Fan Wang* Li Yi Leonidas Guibas
* Equal contribution
Query Retrieval using AlexNet features
Kar et al, CVPR’15
Huang et al, SIGGRAPH’15 Su et al, SIGGRAPH’14
Fg/bg segmentation 2D-3D Correspondence Non-convex iterative optimization Keypoint detection 2D image part segmentation 3D shape part segmentation
Observed view
(HoG feature as an example)
(HoG feature as an example)
Learn from a dataset of many objects with multi-view features
Learn from a dataset of multi-view features
d
The dataset is generated by rendering 3D models
The dataset is generated by rendering large-scale 3D models
http://shapenet.cs.stanford.edu
Learn from a dataset of multi-view features
Observed view image Novel view feature
(HoG feature as an example)
Observed view image Novel view feature
(HoG feature as an example)
Observed view image Novel view feature
(HoG feature as an example)
(HoG feature as an example)
Observed view image Novel view feature
Observed view image Novel view feature
(HoG feature as an example)
Observed view image Novel view feature
(HoG feature as an example)
Observed view image Novel view feature
(HoG feature as an example) + + …
(HoG feature as an example) + + …
Observed view image Novel view feature
(HoG feature as an example) + + …
Observed view image Novel view feature + + …
0.1 0.4 0.3
Locally Linear Reconstruction
(HoG feature as an example) + + …
Observed view image Novel view feature + + …
0.1 0.4 0.3
Locally Linear Reconstruction
(HoG feature as an example) + + …
Observed view image Novel view feature + + …
0.1 0.4 0.3
Locally Linear Reconstruction
+
+ +
+ …
…
0.1 0.4 0.3
Observed view image Novel view feature
(HoG feature as an example)
Locally Linear Reconstruction Inter-shape relationship
+
+ +
+ …
…
0.1 0.4 0.3
Observed view image Novel view feature
Locally Linear Reconstruction Inter-shape relationship
(HoG feature as an example)
Observed view Shape Collection Novel view
Observed view Shape Collection Surrogate suitability matrix Novel view
Shape Collection
𝐵 𝐶
Novel view Observed view
Assume
A, 𝐶 are discrete random variables
Shape Collection
𝐵 𝐶
Novel view Observed view
Assume
A, 𝐶 are discrete random variables (𝑏1, 𝑐1), (𝑏2, 𝑐2), are i.i.d samples of (𝐵, 𝐶)
𝑏1 𝑐1
e.g.
𝑐2 𝑏2
Shape Collection
𝐵 𝐶
Novel view Observed view
Assume
A, 𝐶 are discrete random variables (𝑏1, 𝑐1), (𝑏2, 𝑐2), are i.i.d samples of (𝐵, 𝐶)
𝑏1 𝑐1
e.g.
𝑐2 𝑏2
𝛿 𝐵; 𝐶 = log 𝑄(𝑐1 = 𝑐2|𝑏1 = 𝑏2) Surrogate suitability:
Shape Collection
𝐵 𝐶
Novel view Observed view
Assume
A, 𝐶 are discrete random variables (𝑏1, 𝑐1), (𝑏2, 𝑐2), are i.i.d samples of (𝐵, 𝐶)
𝑏1 𝑐1
e.g.
𝑐2 𝑏2
𝛿 𝐵; 𝐶 = log 𝑄(𝑐1 = 𝑐2|𝑏1 = 𝑏2) Surrogate suitability:
How well can the sameness at A predict the sameness at B?
Shape Collection
𝐵 𝐶
Novel view Observed view
Assume
A, 𝐶 are discrete random variables (𝑏1, 𝑐1), (𝑏2, 𝑐2), are i.i.d samples of (𝐵, 𝐶)
𝑏1 𝑐1
e.g.
𝑐2 𝑏2
𝛿 𝐵; 𝐶 = log 𝑄(𝑐1 = 𝑐2|𝑏1 = 𝑏2) Surrogate suitability:
How well can the sameness at A predict the sameness at B? Cross-view transfer
𝐼𝑆: Renyi-entropy Derivation shows
Sample complexity: tight bound Θ 𝑊
𝐵 + 𝑊 𝐶
Derivation shows where 𝑊
𝐵 and 𝑊 𝐶 are vocabulary size of 𝐵 and 𝐶
Sample complexity: tight bound Θ 𝑊
𝐵 + 𝑊 𝐶
Derivation shows where 𝑊
𝐵 and 𝑊 𝐶 are vocabulary size of 𝐵 and 𝐶
Theoretically optimal algorithm is proposed that reaches the bound
Sample complexity: tight bound Θ 𝑊
𝐵 + 𝑊 𝐶
Derivation shows where 𝑊
𝐵 and 𝑊 𝐶 are vocabulary size of 𝐵 and 𝐶
Strong connection with Mutual Information Theoretically optimal algorithm is proposed that reaches the bound
Novel view Observed view
𝐶
Novel view Observed view
𝐶
Novel view Observed view
𝐶
+
+ +
+ …
…
0.1 0.4 0.3
Observed view image Novel view feature
Inter-shape relationship
+
+ +
+ …
…
0.1 0.4 0.3
Observed view image Novel view feature
Inter-shape relationship: Knowledge transfer from 3D shape database to new instance
Inter-shape relationship
+
+ +
+ …
…
0.1 0.4 0.3
Observed view image Novel view feature
Intra-shape relationship
Inter-shape relationship: Knowledge transfer from 3D shape database to new instance Intra-shape relationship: Knowledge transfer from observed view to novel view
HoG L2 Ours (combined HoG)
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HoG L2 Ours (combined HoG)
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HoG L2 Ours (combined HoG)
swivel base
vertical bars
(Measured by Average Precision on Fine-grained retrieval for Chairs)
200
(Measured by Average Precision on Fine-grained retrieval for Chairs)
80
Cross-view retrieval rank
Controlled diagnosis on renderings
“predictability” between random variables.