foundations & core in computer vision: a system perspective ce liu microsoft research new...
TRANSCRIPT
Foundations & Core in Computer Vision: A System Perspective
Ce Liu
Microsoft Research New England
Vision vs. Learning
• Computer vision: visual application of machine learning?
• Data features algorithms data
• ML: design algorithms given input and output data
• CV: find the best input and output data given available algorithms
Theoretical vs. Experimental
• Theoretical analysis of a visual system– Best & worst cases
– Average performance
• Theoretical analysis is challenging as many visual distributions are hard to model (signal processing: 2nd order processes, machine learning: exponential families)
• Experimental approach: full spectrum of system performance as a function of the amount of data, annotation, number of categories, noise, and other conditions
Quality vs. Speed
• HD videos, billions of images to index• Real time & 90% vs. one hour per frame & 95%?• Mechanism to balance quality and speed in modeling
Automatic vs. semi-automatic
• Common review feedback: parameters are hand-tuned; not clear how to set the parameters
• Vision system user feedback: I don’t know how to tweak parameters!
• Computer-oriented vs. human-oriented representations
• Human-in-the-loop (collaborative) vision– How to optimally use humans (what, which and how
accurate) beyond traditional active learning
– Model design by crowd-sourcing
– Learning by subtraction
Algorithms vs. Sensors
• Two approaches to solving a vision problem– Look at images, design algorithms, experiment, improve…
– Look at cameras, design new/better sensors, …
• Cameras for full-spectrum, high res, low noise, depth, motion, occluding boundary, object, …
• What’s the optimal sensor/device for solving a vision problem?
• What’s the limit of sensors?
Thank you!
Ce Liu
Microsoft Research New England