2. Introduction
2
Co-founder & Head
of Analytics
Insights as Stories
100+ Clients
Help apply & adopt
Analytics
“Simplify Data
Science for all”
Our data science platform,
Gramex is now open-sourced
3. What was the count really?!
3
https://www.theguardian.com/world/2018/sep/06/donald-trump-inauguration-crowd-size-photos-edited#img-1
4. Machine Learning 101
4
New Input
Desired
Outcome
Machine learning
how to do the job
Known Input
Known
Outcome
“Programs that solve
the problem”
“Programs that learn
to solve the problem”
vs
5. Why Deep Learning?
5
Input Output
Identify features
to teach model
Traditional Machine Learning
Deep Learning
Person
Name
Input Output
Model automatically identifies
features to learn
Person
Name
https://www.cs.toronto.edu/~ranzato/publications/taigman_cvpr14.pdf
8. Approaches to Crowd Counting
8
Occlusion
Density Difference
Perspective Distortion
Camera angle
9. Counting using Density-based Estimations
9
Preserve spatial information
Localize count
Handle scale variations
No longer looking for a head!
https://blog.dimroc.com/2017/11/19/counting-crowds-and-lines/
10. Let’s save the Penguins
10
Penguin populations are
dwindling in Antarctica
and we must act now
Source: Giphy (https://giphy.com/gifs/push-bwLowbhUWm2lO)
14. Approach
14
https://arxiv.org/pdf/1707.09605.pdf
• High-level prior to classify image into buckets
• Density estimation to create the density map
Input an image Density Map Estimate the countSplit into 9 patches
• NC6 v3 virtual machine with V100 GPU card
• Trained for 200 epochs, MAE for the model : ~10.5
Work done by Gramener in partnership with Microsoft AI for Earth
16. Sizing up human crowds
16
Getting estimates of
people can be of use in
several use cases such
as security, retail and
marketing
Source: Giphy (https://giphy.com/gifs/nbc-thanksgiving-xUOxeRSgzGd7rbAqWs)
23. Learnings: Enterprise Application
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• Label your own data
• Look out for practical data challenges
• Don’t stop at counts - go for actionability
• Build it into the business workflow
• Sensitize users on low accuracy
• Plan for model refresh
24. Best time to buy a burger?!
24
https://blog.dimroc.com/2017/11/19/counting-crowds-and-lines/
25. Additional References
• Single-Image Crowd Counting via Multi-Column Convolutional Neural Network, 2016 IEEE Conference on
Computer Vision and Pattern Recognition (CVPR), 589-597; Zhang, Yingying Zhou, Desen Chen, Siqin Gao,
Shenghua Ma, Yi,
• CNN-based Cascaded Multi-task Learning of High-level Prior and Density Estimation for Crowd Counting,
Vishwanath A. Sindagi, Vishal M. Patel
• Counting in the Wild, Carlos Arteta, Victor Lempitsky, Andrew Zisserman, University of Oxford, UK; Skoltech,
Russia (https://www.robots.ox.ac.uk/~vgg/data/penguins/)
• CrowdNet: A Deep Convolutional Network for Dense Crowd Counting, 2016; Boominathan, Lokesh
Kruthiventi, Srinivas S S Babu, R. Venkatesh
• Cross-scene crowd counting via deep convolutional neural networks, Proceedings of the IEEE Computer
Society Conference on Computer Vision and Pattern Recognition, 2015, 833-841; Zhang, Cong Li, Hongsheng
Wang, Xiaogang Yang, Xiaokang.
• Switching convolutional neural network for crowd counting, Sam, Deepak Babu Surya, Shiv Babu, R.
Venkatesh, Proceedings - 30th IEEE Conference on Computer Vision and Pattern Recognition, CVPR 2017,
4031-4039
25