Auto encoder structure An autoencoder is a feedforward neural network hat learns to predict the input corrupted by noise compressed Data itself in the output Input Output The input-to-hidden part corresponds to an encoder The hidden-to-output part corresponds to a decoder. Input and output are of Erode Docomo the same dimension and encoder decoder SIze https://towardsdatascience.com/deep-autoencoders-using-tensorflow-c68f075fd1a3 Ch10. Auto and variational encoders v. 9r6
Auto encoder Structure An autoencoder is a feedforward neural network that learns to predict the input (corrupted by noise) itself in the output. 𝑦 (𝑖) = 𝑥 (𝑖) • The input-to-hidden part corresponds to an encoder • The hidden-to-output part corresponds to a decoder. • Input and output are of the same dimension and size. Ch10. Auto and variational encoders v.9r6 6 https://towardsdatascience.com/deep-autoencoders-using-tensorflow-c68f075fd1a3 Input Output encoder decoder
nput output Theory x->F->X X z=o(WX+b) Wσ W′ =o(Wz+b)--( 水 Autoencoders are trained to minimize reconstruction errors(such as squared errors) often referred to as the loss(L) x->F->X By combining )and(x) L(X,Xx)=||X×212 Xx(Wσ(WⅩ+b)+b)|2 Ch10. Auto and variational encoders v.9r6
Theory • x->F->x’ • z=(Wx+b)-----------(*) • x’=’(W’z+b’) -------(**) • Autoencoders are trained to minimize reconstruction errors (such as squared errors), often referred to as the "loss (L)": • By combining (*) and (**) • L(x,x’)=||x-x’||2 • =||x-’(W’ (Wx+b)+b’)||2 Ch10. Auto and variational encoders v.9r6 7 ’ x->F->x’ W W’
Exercise 1 ° How many input hidden layers, output Input Output layers for the figure imprese vara shown? How many neurons in these layers? What is the relation between the number rode of input and output neurons ? Ch10. Auto and variational encoders v.9r6 8
Exercise 1 • How many input, hidden layers, output layers for the figure shown? • How many neurons in these layers? • What is the relation between the number of input and output neurons? Ch10. Auto and variational encoders v.9r6 8 Input Output
Answer 1 Input Output How many input hidden ccaresse Dara layers, output layers for the figure shown? Answer: 1 input, 3 hidden, 1 output layers How many neurons in these layers? Answer: input(4) Enode Decode hidden(3, 2, 3), output (4 What is the relation between the number of input and output neurons? Answer: same Ch10. Auto and variational encoders v.9r6
Answer 1 • How many input, hidden layers, output layers for the figure shown? – Answer:1 input, 3 hidden,1 output layers • How many neurons in these layers? – Answer: input(4), hidden(3,2,3), output (4) • What is the relation between the number of input and output neurons? – Answer: same Ch10. Auto and variational encoders v.9r6 9 Input Output
Architecture Encoder and decoder Original Information aInIng can use Autoencoder typical Encoder backpropagation methods Compressed Information Decoder https://towardsdatascience.com/how-to reduce- image-noises-by-autoencoder- Restored Information 65d5e6de543 Ch10. Auto and variational encoders v. 9r6
Architecture • Encoder and decoder • Training can use typical backpropagation methods Ch10. Auto and variational encoders v.9r6 10 https://towardsdatascience.com/how-toreduce-image-noises-by-autoencoder- 65d5e6de543