Shadow Detection Based on Regions of Light Sources for Object Extraction in Nighttime Video.
Intelligent video surveillance systems detect pre-configured surveillance events through background modeling, foreground and object extraction, object tracking, and event detection. Shadow regions inside video frames sometimes appear as foreground objects, interfere with ensuing processes, and finally degrade the event detection performance of the systems. Conventional studies have mostly used intensity, color, texture, and geometric information to perform shadow detection in daytime video, but these methods lack the capability of removing shadows in nighttime video. In this paper, a novel shadow detection algorithm for nighttime video is proposed; this algorithm partitions each foreground object based on the object's vertical histogram and screens out shadow objects by validating their orientations heading toward regions of light sources. From the experimental results, it can be seen that the proposed algorithm shows more than 93.8% shadow removal and 89.9% object extraction rates for nighttime video sequences, and the algorithm outperforms conventional shadow removal algorithms designed for daytime videos.
Telecommunications Technology Association, 47 Bundang-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 13591, Korea. lgbch2@tta.or.kr.
Gil-Beom
GB
Lee
School of Electronics and Information Engineering, Korea Aerospace University, 76 Hanggongdaehak-ro Deogyang-gu, Goyang-si, Gyeonggi-do 10540, Korea. artistic@kau.ac.kr.
Myeong-Jin
MJ
Lee
School of Electronics and Information Engineering, Korea Aerospace University, 76 Hanggongdaehak-ro Deogyang-gu, Goyang-si, Gyeonggi-do 10540, Korea. wklee@kau.ac.kr.
Woo-Kyung
WK
Lee
Satrec Initiative, 21 Yuseong-daero 1628beon-gil Yuseong-gu, Daejeon 34054, Korea. jhpark@satreci.com.
Joo-Heon
JH
Park
School of Electronics and Information Engineering, Korea Aerospace University, 76 Hanggongdaehak-ro Deogyang-gu, Goyang-si, Gyeonggi-do 10540, Korea. taehwan.kim@kau.ac.kr.
Tae-Hwan
TH
Kim
nighttime video; object extraction; regions of light sources; shadow detection; shadow removal; vertical histogram; video analytics; video surveillance