1. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
Using Morphable Face Model to Improve
Stereo Reconstruction and Visualising the
Model on a Smartphone
HARDIK JAIN
Under the Guidance of
Prof. Olaf HELLWICH
Prof. RS ANAND
2. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
PRESENTATION OUTLINE
Introduction
Motivation
Research Methodology
Results and Evaluation
Visualisation
Conclusion and Scope for Future Work
Further Reading
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3. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
INTRODUCTION
Face Reconstruction
Multiple Image Reconstruction
Visual structure from motion
Stereo Reconstruction
Single Image Reconstruction
3D Morphable Model
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4. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
3D Morphable Model
Statistical model of face meshes which are in dense
correspondence.
Principal component analysis (PCA) is performed on
these set of 𝑀 meshes.
Mean shape ҧ𝑠, 𝑀 − 1 Principal Components 𝑆𝑖 and 𝜎𝑠,𝑖
2
eigen values
Shape parameter vector cs = 𝛼1, … , 𝛼 𝑀−1
𝑇
iisi
M
i
model SsS 2
,
1
1=
=
INTRODUCTI
ON
Single Image Reconstruction
Morphable
Model
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5. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
MOTIVATION Stereo Reconstruction
Stereo Model
Stereo
Model
High
Quality
Face Scan
Stereo Model and High
Quality Scan Cloud
Compare
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6. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
Face Model
MOTIVATION Single Image Reconstruction
Face Image Face Model
Face Model Cloud
Compare
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7. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
MOTIVATION
Single
Image
Reconstruc
tion
Stereo
Model
Deformed Face
Model
Shape
Information
Texture &
Smoothness
Deformation
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8. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
RESEARCH METHODOLOGY
Morphable
Model
Stereo Pair
Image
Deformed Face
Model
Single Image
Landmarking
Pose Estimation
Shape Fitting
Texture Extraction
Global& Local
Deformation
Stereo
Reconstruction
Face Model
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Method Overview
9. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
Landmarking Annotation
To find 𝐅 = 𝑥1 𝑦1, … , 𝑥 𝑛 𝑦𝑛
𝑇
∈ ℝ2𝑛
Obtain Face Bounding Box
Cascade based Regression Method
Initial estimate is centred to the Bounding box
Regressor rt 𝐼, F(t)
F(t+1) = F(t) + rt 𝐼, F(t)
RESEARCH
METHODOLOGY
Single Image Reconstruction
Landmark Annotated
Face Image
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10. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
Pose Estimation
Camera Orientation Matrix, 𝐏
𝐱 𝒊 = 𝐏𝐗 𝒊 , where 𝐱 𝒊∈ ℝ2 and 𝐗 𝒊∈ ℝ3
Affine Camera Model
Gold Standard Algorithm of Hartley & Zisserman
RESEARCH
METHODOLOGY
Single Image Reconstruction
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2D Landmark
Points
3D Points
on MM
11. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
Shape Fitting
Estimation of shape Parameter 𝐜s
Probabilistic Approach
Minimise 𝐸 = σ𝑖=1
3𝑁 𝑦 𝑚𝑜𝑑𝑒𝑙2𝐷,𝑖 −𝑦 𝑖
2
2 𝜎 2𝐷,𝑖
2 + 𝐜s
2
Face Image Face Shape
Model
RESEARCH
METHODOLOGY
Single Image Reconstruction
iisi
M
i
model SsS 2
,
1
1=
=
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25
12. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
Texture Extraction
Obtained from Face Image
Isomap Algorithm
Retaining Geodesic Distance
Texture Map
RESEARCH
METHODOLOGY
Single Image Reconstruction
Face Image
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13. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
STEREO RECONSTRUCTION
Obtain stereo pair images
Camera Calibration
Keypoint Detection
Triangulation
Dense Reconstruction
RESEARCH
METHODOLOGY
Stereo
Model
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14. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
DEFORMATION
Motivation
Surface Registration
Approach
Two-step deformation
Global and Local transformation
𝒗𝑗 = Φ𝑙𝑜𝑐𝑎𝑙 ∘ Φ 𝑔𝑙𝑜𝑏𝑎𝑙 (𝒗 𝑗)
RESEARCH
METHODOLOGY
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15. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
Global Deformation
Using few control points
Radial Basis Function 𝜙 𝑥, 𝑋𝑐 = 𝜙 𝑥 − 𝑋𝑐
Weighted Combination of RBF
𝑔 𝑥 =
𝑘=1
𝑁
𝜆 𝑐 𝜙 𝑥 − 𝑋𝑐
Gaussian Kernel 𝜙𝑖,𝑐 𝑥 = 𝑒
−
𝑥 𝑖− 𝑋 𝑐
2
2𝜎2
RESEARCH
METHODOLOGY
Deformation
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16. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
𝜆 𝑐 = 𝜙−1 𝑔 applied on Sourcepartial
𝜆 𝑟,1
⋮
𝜆 𝑟,𝑁
=
𝜙1,1 ⋯ 𝜙1,𝑁
⋮ ⋱ ⋮
𝜙 𝑉,1 ⋯ 𝜙 𝑉,𝑁
−1
𝑔 𝑟,1
⋮
𝑔 𝑟,𝑉
, for r = (x,y,z)
Face unspecific results for N=25
Few 100 milliseconds on intel quad core
computer
RESEARCH
METHODOLOGY
Deformation Global Deformation
Weight Coefficients (𝜆 𝑐)
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17. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
Local Deformation
Smoothen the overshoots of RBF
Influence of nearby neighbors
Non-rigid transformation by k nearest
neighbouring vertices
Procrustes Analysis
Affine transformation (𝐁𝑖 and 𝐭 𝑖)
RESEARCH
METHODOLOGY
Deformation
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18. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
Φlocal 𝑣 = w0 𝑣 𝐁0 𝑣 + 𝐭0 + σi=1
𝐾
wi 𝑣 𝐁i 𝑣 + 𝐭i
wi 𝑣 =
1
𝐾
d− 𝑣 𝑖− 𝑣
d
, 𝑑 = σi=1
𝐾
𝑣𝑖 − 𝑣
w0(𝑣) =
1
𝐾
𝐾 = 12
Requires Few seconds
RESEARCH
METHODOLOGY
DEFORMATION
Local Deformation
1
5
4
2
3
6
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19. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
DEFORMED FACE MODEL
RESULTS AND
EVALUATION
Face Image Face Model Deformed Face Model
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20. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
EVALUATION
RESULTS AND
EVALUATION
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3.5532 3.3073 2.8738
21. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
EVALUATION
RESULTS AND
EVALUATION
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4.2734 2.9985 2.0133
22. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
EVALUATION
RESULTS AND
EVALUATION
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2.9982 2.5212 2.174
23. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
VISUALISATION
Virtual Reality
Using Smartphone and Cardboard Viewer
Android phones with support of OpenGL ES 3.1
Implemented on SDK provided by Google
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24. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
Smartphone View
VISUALISATION
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25. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
CONCLUSION AND SCOPE
FOR FUTURE WORK
Improved reconstruction after information
fusion
Technique Could be used for various
other objects
Cheap alternative visualisation platform
Smartphone visualisation Environment
Improvement
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26. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
FURTHER READING
V. Blanz and T. Vetter, “A morphable model for the synthesis of 3D faces,”
in Proceedings of the 26th annual conference on Computer graphics and
interactive techniques. ACM Press/Addison-Wesley Publishing Co., 1999,
pp. 187–194.
P. Huber, G. Hu, R. Tena, P. Mortazavian, W. P. Koppen, W. Christmas, M.
Ratsch, and J. Kittler, “A multiresolution 3D morphable face model and
fitting framework,” in 11th International Joint Conference on Computer
Vision, Imaging and Computer Graphics Theory and Applications, February
2016.
P. Huber, Z.-H. Feng, W. Christmas, J. Kittler, and M. Rätsch, “Fitting 3D
morphable models using local features,” arXiv preprint arXiv:1503.02330,
2015.
V. Kazemi and J. Sullivan, “One millisecond face alignment with an
ensemble of regression trees,” in Computer Vision and Pattern Recognition
(CVPR), 2014 IEEE Conference on. IEEE, 2014, pp. 1867– 1874.
R. W. Sumner, J. Schmid, and M. Pauly, “Embedded deformation for shape
manipulation,” ACM Transactions on Graphics (TOG), vol. 26, no. 3, p. 80,
2007.
“Cardboard.” https://developers.google.com/cardboard/overview, 2016.
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27. Computer Vision and Remote Sensing
Technical University Berlin, Germany
Department of Electrical Engineering
IIT Roorkee, India
FURTHER READING
Thank You