AdaBoost & Its Applications
Outline
Overview
The AdaBoost Algorithm
How and why AdaBoost works?
AdaBoost for Face Detection
AdaBoost & Its Applications
Overview
Introduction
AdaBoost
Adaptive
A learning algorithm
Building a strong classifier a lot of weaker ones
Boosting
AdaBoost Concept
.
.
.
weak classifiers
slightly better than random
strong classifier
Weaker Classifiers
.
.
.
weak classifiers
slightly better than random
strong classifier
训练一个弱分类器(特征f)就是在当前权重分布的情况下,确定f 的最优阈值以及不等号的方向,使得这个弱分类器(特征f)对所有训练样本的分类误差最低。
The Strong Classifiers
.
.
.
weak classifiers
slightly better than random
strong classifier
How good the strong one will be?
AdaBoost & Its Applications
The AdaBoost Algorithm
The AdaBoost Algorithm
Given:
Initialization:
For :
Find classifier which minimizes error wrt Dt ,.,
Weight classifier:
Update distribution:
The AdaBoost Algorithm
Given:
Initialization:
For :
Find classifier which minimizes error wrt Dt ,.,
Weight classifier:
Update distribution:
Output final classifier:
AdaBoost算法及应用.. 来自淘豆网m.daumloan.com转载请标明出处.
