Lecture 6: Recognition & Detection - - PowerPoint PPT Presentation
Computer Vision: from Recognition to Geometry Lecture 6: Recognition & Detection http://media.ee.ntu.edu.tw/courses/cv/18F/ FB: NTUEE Computer Vision Fall 2018 Yu-Chiang Frank Wang , Associate Professor Dept. Electrical
http://media.ee.ntu.edu.tw/courses/cv/18F/ FB: NTUEE Computer Vision Fall 2018
2018/10/24
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China is forecasting a trade surplus of $90bn (£51bn) to $100bn this year, a threefold increase on 2004's $32bn. The Commerce Ministry said the surplus would be created by a predicted 30% jump in exports to $750bn, compared with a 18% rise in imports to $660bn. The figures are likely to further annoy the US, which has long argued that China's exports are unfairly helped by a deliberately undervalued yuan. Beijing agrees the surplus is too high, but says the yuan is only one factor. Bank of China governor Zhou Xiaochuan said the country also needed to do more to boost domestic demand so more goods stayed within the country. China increased the value of the yuan against the dollar by 2.1% in July and permitted it to trade within a narrow band, but the US wants the yuan to be allowed to trade freely. However, Beijing has made it clear that it will take its time and tread carefully before allowing the yuan to rise further in value.
China, trade, surplus, commerce, exports, imports, US, yuan, bank, domestic, foreign, increase, trade, value
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class class
training data surprise relative entropy between when observing and
inputs class labels
desired result of training:
neuron outputs for neuron outputs for encourages neuron output to match training data
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Dropout: A simple way to prevent neural networks from overfitting [Srivastava JMLR 2014]
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Dropout: A simple way to prevent neural networks from overfitting [Srivastava JMLR 2014]
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Credit: Andrew Ng
Batch Normalization: Accelerating Deep Network Training by Reducing Internal Covariate Shift [Ioffe and Szegedy 2015]
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Credit: Fei-Fei Li
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China is forecasting a trade surplus of $90bn (£51bn) to $100bn this year, a threefold increase on 2004's $32bn. The Commerce Ministry said the surplus would be created by a predicted 30% jump in exports to $750bn, compared with a 18% rise in imports to $660bn. The figures are likely to further annoy the US, which has long argued that China's exports are unfairly helped by a deliberately undervalued yuan. Beijing agrees the surplus is too high, but says the yuan is only one factor. Bank of China governor Zhou Xiaochuan said the country also needed to do more to boost domestic demand so more goods stayed within the country. China increased the value of the yuan against the dollar by 2.1% in July and permitted it to trade within a narrow band, but the US wants the yuan to be allowed to trade freely. However, Beijing has made it clear that it will take its time and tread carefully before allowing the yuan to rise further in value.
China, trade, surplus, commerce, exports, imports, US, yuan, bank, domestic, foreign, increase, trade, value
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Credit: Matt Brown 24
Credit: Silvio Savarese 25
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Robust to occlusion Works with less texture Minimize wrong matches Robust to expected variations Maximize correct matches More distinctive representation Robust detection Precise localization
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σ Original image
4 1
2 = σ
Sampling with step σ4 =2 σ σ σ
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(detector + descriptor, 640×480 img) http://www.vision.ee.ethz.ch/~surf
[Bay, ECCV’06], [Cornelis, CVGPU’08]
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Features from Accelerated Segment Test, ECCV 06
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China is forecasting a trade surplus of $90bn (£51bn) to $100bn this year, a threefold increase on 2004's $32bn. The Commerce Ministry said the surplus would be created by a predicted 30% jump in exports to $750bn, compared with a 18% rise in imports to $660bn. The figures are likely to further annoy the US, which has long argued that China's exports are unfairly helped by a deliberately undervalued yuan. Beijing agrees the surplus is too high, but says the yuan is only one factor. Bank of China governor Zhou Xiaochuan said the country also needed to do more to boost domestic demand so more goods stayed within the country. China increased the value of the yuan against the dollar by 2.1% in July and permitted it to trade within a narrow band, but the US wants the yuan to be allowed to trade freely. However, Beijing has made it clear that it will take its time and tread carefully before allowing the yuan to rise further in value.
China, trade, surplus, commerce, exports, imports, US, yuan, bank, domestic, foreign, increase, trade, value
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Images from Dave Kauchak 47
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K m j i j i
m h m h h h
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) ( ), ( min 1 ) , histint(
Need less data Coarser representation
Need more data Finer representation
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Of all the sensory impressions proceeding to the brain, the visual experiences are the dominant ones. Our perception of the world around us is based essentially on the messages that reach the brain from our eyes. For a long time it was thought that the retinal image was transmitted point by point to visual centers in the brain; the cerebral cortex was a movie screen, so to speak, upon which the image in the eye was projected. Through the discoveries of Hubel and Wiesel we now know that behind the
considerably more complicated course of events. By following the visual impulses along their path to the various cell layers of the optical cortex, Hubel and Wiesel have been able to demonstrate that the message about the image falling on the retina undergoes a step-wise analysis in a system of nerve cells stored in columns. In this system each cell has its specific function and is responsible for a specific detail in the pattern of the retinal image.
China is forecasting a trade surplus of $90bn (£51bn) to $100bn this year, a threefold increase on 2004's $32bn. The Commerce Ministry said the surplus would be created by a predicted 30% jump in exports to $750bn, compared with a 18% rise in imports to $660bn. The figures are likely to further annoy the US, which has long argued that China's exports are unfairly helped by a deliberately undervalued yuan. Beijing agrees the surplus is too high, but says the yuan is only one factor. Bank of China governor Zhou Xiaochuan said the country also needed to do more to boost domestic demand so more goods stayed within the country. China increased the value of the yuan against the dollar by 2.1% in July and permitted it to trade within a narrow band, but the US wants the yuan to be allowed to trade freely. However, Beijing has made it clear that it will take its time and tread carefully before allowing the yuan to rise further in value.
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k = 1 k = 2 k = 3
Training images Interest point detection Clustering (dictionary learning) Feature Encoding Quantization (w/ normalization)
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k = 1 k = 2 k = 3
Interest point detection Clustering (dictionary learning) Feature Encoding Quantization (w/ normalization)
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[Lazebnik et al. CVPR 2006]
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China is forecasting a trade surplus of $90bn (£51bn) to $100bn this year, a threefold increase on 2004's $32bn. The Commerce Ministry said the surplus would be created by a predicted 30% jump in exports to $750bn, compared with a 18% rise in imports to $660bn. The figures are likely to further annoy the US, which has long argued that China's exports are unfairly helped by a deliberately undervalued yuan. Beijing agrees the surplus is too high, but says the yuan is only one factor. Bank of China governor Zhou Xiaochuan said the country also needed to do more to boost domestic demand so more goods stayed within the country. China increased the value of the yuan against the dollar by 2.1% in July and permitted it to trade within a narrow band, but the US wants the yuan to be allowed to trade freely. However, Beijing has made it clear that it will take its time and tread carefully before allowing the yuan to rise further in value.
China, trade, surplus, commerce, exports, imports, US, yuan, bank, domestic, foreign, increase, trade, value
Slide from A. Karpathy 65
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Gradient based or CNN features, usually based on summary representation with classification/voting results Rescore each proposed object based on the entire candidate set
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Slide from K. Grauman, B. Leibe
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Viola and Jones. Rapid Object Detection using a Boosted Cascade of Simple Features (2001). 86
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Image credit: Justin Johnson
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Slides by Justin Johnson 95
Slides by Justin Johnson
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Slides by Justin Johnson
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Slides by Justin Johnson
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Uijilings et al. IJCV 2013 100
http://arxiv.org/pdf/1311.2524.pdf
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http://arxiv.org/pdf/1311.2524.pdf
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https://arxiv.org/pdf/1504.08083.pdf
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https://arxiv.org/pdf/1504.08083.pdf
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Uijilings et al. IJCV 2013
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https://arxiv.org/pdf/1506.01497.pdf
Image credit: http://zh.gluon.ai/chapter_computer-vision/object-detection.html
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Slide credit: Ross Girshick
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