Browsing by Author "Chan, Chia-Hsin"

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A NOVEL VIDEO SUMMARIZATION METHOD FOR MULTI-INTENSITY ILLUMINATED INFRARED VIDEOS
(2013-01-01)
Chuang, Jen-Hui
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Tsai, Wen-Jing
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Chan, Chia-Hsin
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Teng, Wen-Chih
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Lu, I-Chun
In nighttime video surveillance, proper illumination plays a key role for the image quality. For ordinary IR-illuminators with fixed intensity, faraway objects are often hard to identify due to insufficient illumination while nearby objects may suffer from over-exposure, resulting in image foreground/background of poor quality. In this paper we proposed a novel video summarization method which utilizes a novel multi-intensity IR-illuminator to generate images of human activities with different illumination levels. By adopting GMM-based foreground extraction procedure for images acquired for each illumination level, foreground objects with most plausible quality can be selected and merged with a preselected representation for still background. The result brings out a reasonable video summary for moving foreground, which is generally unachievable for nighttime surveillance videos.
Adaptive Accordion Transformation Based Video Compression Method on HEVC
(2016)
Chan, Chia-Hsin
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Ji, Hong-Syun
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Tsai, Wen-Jiin
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資訊工程學系
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Department of Computer Science
Fast processing speed and high compression ratio are always expected for video coding. But generally it is hard to compromise between each other since high compression ratio usually requires high coding complexities. Ouni et al. proposed a novel method called accordion-based (ACC) coding in which multiple video frames are combined into an accordion-like representation for compression and it can achieve high compression ratio with low coding complexity. For low-motion videos at high bit-rates, its coding efficiency is close to H.264/AVC. However, it may no longer have benefit when applying the ACC to HEVC because HEVC has much better coding efficiency than H.264/AVC. Besides, it is not likely that all the frames in a video sequence are low-motion and thus suitable for ACC coding. To cope with these problems, in this paper we propose an adaptive method which dynamically switches between accordion-based coding and traditional HEVC coding according to the characteristics of video frames. The experiment result shows that the proposed method can achieve up to 11.5% of total bit-rate saving and 56.1% of encoding time saving, compared to traditional HEVC coding.
Improve load balancing and coding efficiency of tiles in high efficiency video coding by adaptive tile boundary
(2017-01-01)
Chan, Chia-Hsin
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Tu, Chun-Chuan
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Tsai, Wen-Jiin
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資訊工程學系
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Department of Computer Science
High efficiency video coding (HEVC) not only improves the coding efficiency drastically compared to the well-known H.264/AVC but also introduces coding tools for parallel processing, one of which is tiles. Tile partitioning is allowed to be arbitrary in HEVC, but how to decide tile boundaries remains an open issue. An adaptive tile boundary (ATB) method is proposed to select a better tile partitioning to improve load balancing (ATB-LoadB) and coding efficiency (ATB-Gain) with a unified scheme. Experimental results show that, compared to ordinary uniform-space partitioning, the proposed ATB can save up to 17.65% of encoding times in parallel encoding scenarios and can reduce up to 0.8% of total bit rates for coding efficiency. (C) 2017 SPIE and IS&T
Local Feature-Based Photo Album Compression by Eliminating Redundancy of Human Partition
(2017-01-01)
Chan, Chia-Hsin
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Chen, Bo-Hsyuan
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Tsai, Wen-Jiin
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資訊工程學系
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Department of Computer Science
With the explosive growth of photo uploading on the web, traditional photo album compression using individual image coding is needed to be improved to save the storage spaces. Recently, an advance technique of photo album compression via video compression is proposed which utilizes the similarity between photos to improve the compression performance. In this paper, we modify the original scheme to improve the compression performance when photos containing human beings. Experiment results show that the proposed method outperforms the state-of-the-art method by at most 12.7% of bit-rate savings for compressing photo albums with humans. Comparing with traditional JPEG compression, the proposed method achieves 70% to 85% of bit-rate savings.
MI3: Multi-Intensity Infrared Illumination Video Database
(2015-01-01)
Chan, Chia-Hsin
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Chen, Hua-Tsung
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Teng, Wen-Chih
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Liu, Chin-Wei
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Chuang, Jen-Hui
Vision-based video surveillance systems have gained increasing popularity. However, their functionality is substantially limited under nighttime conditions due to the poor visibility caused by improper illumination. Equipped on night vision cameras, ordinary infrared (IR) illuminators of fixed-intensity usually lead to the imaging problem of overexposure (or underexposure) when the object is too close to (or too far from) the camera. To overcome this limitation, we use a novel multi-intensity IR illuminator to extend the effective range of distance of camera surveillance, and establish in this paper the MI3 (Multi-Intensity Infrared Illumination) database based on such an illuminator. The database contains intensity varying video sequences of several indoor and outdoor scenes. Ground truths including people counting and foreground labelling are provided for different research usages. Performances of related algorithms are tested for demonstration and evaluation.
MULTI-INTENSITY ILLUMINATED INFRARED VIDEO COMPRESSION USING MV-HEVC AND 3D-HEVC
(2017-01-01)
Chan, Chia-Hsin
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Teng, Chiang
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Chuang, Jen-Hui
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資訊工程學系
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Department of Computer Science
Multi-Intensity Illuminated Infrared (MIIR) video is a new type of infrared video which solves the problem of improper illumination conditions for ordinary infrared cameras for nighttime surveillance. However, its time-varying intensity makes it hard to be compressed with traditional video coding methods. In this paper we use MV-HEVC and 3D-HEVC video coding standards, which are originally designed for Multi-view and 3D video coding, to compress the MIIR videos. With the proposed encoding method, the coding structures of MY-and 3D-HEVC can be employed to compress the MIIR video in a more efficient way. Experimental results show that the coding structures of MY and 3D-HEVC can compress such video in a more efficient way, i.e., up to 43.8%/50.1% bitrate reductions with MV/3D-HEVC compared with standalone HEVC compression and 74.3%/80.5% bitrate reductions compared with simulcast HEVC coding in the enhancement layers.
New Application of MV-and 3D-HEVC for Multi-Intensity Illuminated Infrared Video Coding
(2016)
Chan, Chia-Hsin
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Teng, Chiang
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Chuang, Jen-Hui
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資訊工程學系
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Department of Computer Science
MV-HEVC and 3D-HEVC are the extensions of High Efficiency Video Coding (HEVC) originally designed for Multi-view and 3D video coding respectively. In this paper we reveal a new application of using these video coding standards, i.e., to compress the Multi-Intensity Illuminated Infrared (MIIR) video, a new type of infrared video developed to overcome the limitation of improper illumination conditions for nighttime surveillance. With the proposed encoding method for the MDR video, the coding structures of MV- and 3D-HEVC can compress such video in a more efficient way, i.e., up to 13.2%117.6% bitrate reductions with MV/3D-HEVC compared with standalone HEVC compression and 64.4%/68.7% bitrate reductions compared with simulcast HEVC coding. Experiment results also reveal that weighted prediction algorithm in HEVC can be improved to deal with large change of brightness in the MIIR video.