A short introduction to state-of-the-art Computer Vision techniques and the own work of Anna Volokitin. A talk on the occasion of Geek Girls Carrot's meetup #9 in Zurich.
7. Ideally, we want to automatically
answer any question about a
photo or video.
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8. e.g. why is he smiling?
http://i.dailymail.co.uk/i/pix/2012/12/20/article-2250728-1696C1CD000005DC-817_964x628.jpg8
9. Returning to the basic
task of recognition — is it
really that hard?
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10. Block world
• We can write rules for
recognising objects if we have
• perfect lighting
• simple shapes,
• etc
• Example: triangular prism
• Step 1) Find image edges
• Step 2) If any lines make a
triangle, we found it.
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21. Supervised Learning
• A model is way to decide whether an image is a cat or a
dog, based on some parameter
• In this case, parameter is average colour
• Training a model = adjusting parameter to make model
more accurate
is the image mainly this color ?
Yes
No
CAT
DOG
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22. Training
is the image mainly this color ?
Yes
No
CAT
DOG
training set
Model outputs that all cat images are DOG,
so 50% accuracy22
23. Training
is the image mainly this color ?
Yes
No
CAT
DOG
training set
Model outputs that all cat images are DOG,
so 50% accuracy23
24. Training
is the image mainly this color ?
Yes
No
CAT
DOG
training set
Model outputs that all cat images are DOG,
so 50% accuracy24
25. Training
is the image mainly this color ?
Yes
No
CAT
DOG
training set
Model outputs that all cat images are DOG,
so 50% accuracy25
26. Training
is the image mainly this color ?
Yes
No
CAT
DOG
training set
100% accuracy, finally. Done training.26
36. Summary
• To quantify meaning, CV breaks problems down into
recognition, segmentation, etc.
• Hard because of the huge variability of image appearance
• Supervised learning to discover rules
• Lots of cool applications with CNNs
• recognition
• segmentation
• style transfer …
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