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cv introduction

  • 之前 Udemy 認真的筆記:)

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kernel/filter

kernel/filter:examples

  • Shift, Blur, Sharpening, Gaussian Filter, … etc.

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Convolutional Neural Network for Computer Vision Applicaions

說到介紹 cnn 還是要再一次好好的介紹 CS231

  • Topics
    1. CV: object recongnition
      ML: multiple kernel learning

    2. CV: image segementation
      ML: graphical model

    3. CV: face detection
      ML: multi-task boosting

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    4. CV: action recognition
      ML: low-rank reconstruction

    5. CV: multi-view people counting
      ML: transfer learning

    6. CV: image matching
      ML: energy minimization

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    7. CV: fine-grained object recognition ML: CNNs with co-occurrence layer

    8. CV: patch descriptor learning ML: CNNs with adaptive learning rate

    9. CV: gesture recognition ML: DNNs with adaptive hidden layer

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    10. CV: face age estimation ML: CNNs for hierarchical regression

    11. CV: image co-segmentation ML: Unsupervised CNNs

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Conventional approach vs. Deep Learning

Conventional approach to object recognition

  • Training phase

    • image collection
    • feature extraction
    • classifier training
    • trained classifier
  • Training phase

    • test image
    • feature extraction
    • trained classifier
    • prediction

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Features are the keys

抓特徵!!!

  • off-the-shelf visual features

    • SIFT
    • HoG
    • Constellation model
    • DPM

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  • Features are the keys to recent progress in classification
  • Are handcrafted features optimal ?
  • The optimal features for classification in general vary from task to task, even from category to category

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Conventional approaches vs. Deep Learning

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Deep Learning = Learning hierarchical representations

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Neural Network

Neural nerworks and neurons

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A sigle neuron

這邊可複習 cs231

  • CS231: Lecture 4
  • CS231: Lecture 5

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What is deep neural networks (DNN)

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CNN Intro

  • imagenet

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  • Deep Neural Networks

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  • Ordinary Feedforward DNN with Image

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  • Characteristics of Image

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  • CNN Structure

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Convolutional neural networks

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  • Reduce # of parameters

    • local connectivity

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    • weight sharing

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  • Increate # of parameters

    • CNN with multiple input channels

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    • CNN with multople output maps

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Putting them together

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Convolutional Neural Networks

  • input image
  • Convolution (Learned)
  • Non-linearity
  • Spatial pooling
  • Normalization
  • Feature maps

    • Convolution(Learned)

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    • Non-Linearity

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    • Spatial pooling

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    • Normalization

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AlexNet (代表性!!)

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Object Recognition (2012 ~ 2014)

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