WaldBoost - Learning for Time Constrained Sequential Detection
Šochman, Jan, Matas, Jiří
CVPR 2005, Los Alamitos, USA
Proc. of Conference on Computer Vision and Pattern Recognition (CVPR)
Volume 2, Pages 150-157
June, 2005
Abstract
In many computer vision classification problems, both the error and
time characterizes the quality of a decision. We show that such
problems can be formalized in the framework of sequential
decision-making. If the false positive and false negative error rates
are given, the optimal strategy in terms of the shortest average time
to decision (number of measurements used) is the Wald's sequential
probability ratio test (SPRT). We built on the optimal SPRT test and
enlarge its capabilities to problems with dependent measurements. We
show, how the limitations of SPRT to a priori ordered measurements and
known joint probability density functions can be overcome. We propose
an algorithm with near optimal time - error rate trade-off, called
WaldBoost, which integrates the AdaBoost algorithm for measurement
selection and ordering and the joint probability density estimation
with the optimal SPRT decision strategy. The WaldBoost algorithm is
tested on the face detection problem. The results are superior to the
state-of-the-art methods in average evaluation time and comparable in
detection rates.
Keywords
Adaboost, cascade, Wald's SPRT, sequential analysis, face detection
Bibtex entry
@InProceedings{sochman-waldboost-cvpr05,
author = {{\vS}ochman, Jan and Matas, Ji{\vr}{\'i}},
title = {WaldBoost - Learning for Time Constrained Sequential Detection},
booktitle = {Proc. of Conference on Computer Vision and Pattern Recognition (CVPR)},
address = {Los Alamitos, USA} ,
year = {2005},
month = {June},
day = {20--25},
isbn = {0-7695-2372-2},
publisher = {IEEE Computer Society},
pages = {150--157},
annote = { In many computer vision classification problems, both the
error and time characterizes the quality of a decision. We show that
such problems can be formalized in the framework of sequential
decision-making. If the false positive and false negative error
rates are given, the optimal strategy in terms of the shortest
average time to decision (number of measurements used) is the Wald's
sequential probability ratio test (SPRT). We built on the optimal
SPRT test and enlarge its capabilities to problems with dependent
measurements. We show, how the limitations of SPRT to a priori
ordered measurements and known joint probability density functions
can be overcome. We propose an algorithm with near optimal time -
error rate trade-off, called WaldBoost, which integrates the
AdaBoost algorithm for measurement selection and ordering and the
joint probability density estimation with the optimal SPRT decision
strategy. The WaldBoost algorithm is tested on the face detection
problem. The results are superior to the state-of-the-art methods in
average evaluation time and comparable in detection rates. },
keywords = {Adaboost, cascade, Wald's SPRT, sequential analysis, face detection},
editor = {Schmid, Cordelia and Soatto, Stefano and Tomasi, Carlo},
venue = {San Diego, California, USA },
volume = { 2 },
}