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http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/65860完整後設資料紀錄
| DC 欄位 | 值 | 語言 |
|---|---|---|
| dc.contributor.advisor | 傅楸善 | |
| dc.contributor.author | Cheng-Wei Hsu | en |
| dc.contributor.author | 許承偉 | zh_TW |
| dc.date.accessioned | 2021-06-17T00:13:50Z | - |
| dc.date.available | 2013-07-19 | |
| dc.date.copyright | 2012-07-19 | |
| dc.date.issued | 2012 | |
| dc.date.submitted | 2012-07-09 | |
| dc.identifier.citation | [1] J. M. Brayer, “Introduction to Fourier Transforms for Image Processing,” http://www.cs.unm.edu/~brayer/vision/fourier.html, 2012.
[2] C. H. Chang, “Auto Focus Using Adaptive Step Size Search and Zoom Tracking Algorithm,” Master Thesis, Department of Computer Science and Information Engineering, National Taiwan University, 2005. [3] M. Gamadia, V. Peddigari, N. Kehtarnavaz, S. Y. Lee, and G. Cook, “Real-Time Implementation of Autofocus on the TI DSC Processor,” Proceedings of SPIE, Vol. 5297, pp. 10-18, 2004. [4] J. He, R. Zhou, and Z. Hong, “Modified Fast Climbing Search Auto-focus Algorithm with Adaptive Step Size Searching Technique for Digital Camera,” IEEE Transactions on Consumer Electronics, Vol. 49, No. 2, pp. 257-262, 2003. [5] W. Hsu, “A New Sampling Method of Auto Focus for Camera Phones,” Master Thesis, Department of Computer Science and Information Engineering, National Taiwan University, 2007. [6] S. H. Jin, J. U. Cho, and J. W. Jeon, “FPGA-Based Passive Auto Focus System Using Adaptive Thresholding,” Proceedings of International Joint Conference of SICEICASE, Busan, Korea, pp. 2290–2295, 2006. [7] N. NakaHara, “Passive Autofocus System for a Camera,” United States Patent #7058294, 2006. [8] N. K. C. Nathaniel, P. A. Neow, and H. A. Marcelo Jr., “Practical Issues in Pixel-Based Autofocussing for Machine Vision,” Proceedings of IEEE International Conference on Robotics and Automation, Shanghai, China, Vol. 3, pp. 2791–2796, 2001. [9] N. L. Stauffer, “Active Auto Focus System Improvement,” United States Patent #4367027, 1983. [10] Texas Instrument, “TMS320DM36x Digital Media System-on-Chip (DMSoC) ARM Subsystem User's Guide,” http://www.ti.com/lit/ug/sprufg5a/sprufg5a.pdf, 2012. [11] Texas Instrument, “TMS320DM36x Digital Media System-on-Chip (DMSoC) Video Processing Front End (VPFE) User‘s Guide,” http://www.ti.com/lit/ug/sprufg8c/sprufg8c.pdf, 2012. [12] Wikipedia, “Autofocus,” http://en.wikipedia.org/wiki/Autofocus, 2012. | |
| dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/65860 | - |
| dc.description.abstract | 本論文提出一個應用在TI DM368系統上的監視攝影機對於當前影像是否在適當的焦距上的方法。現今許多攝影機都有自動對焦的功能，可以利用硬體的協助達成主動自動對焦，或者在軟體影像處理的部分計算焦點特徵值，配合搜尋演算法來達成被動自動對焦，這些方法通常需要馬達來調整鏡頭的焦距來達成自動對焦的目的。而本論文所提供的方法，是希望不使用搜尋演算法去比對前後焦點特徵值，而是藉由當前影像焦點特徵值間的相對關係，來達成判定當前影像是否在適當焦距上的功能。 | zh_TW |
| dc.description.abstract | Nowadays most of surveillance cameras have autofocus functionality. It can be classified into two types of methods: active autofocus with auxiliary hardware device and passive autofocus with image processing by calculating focus value and searching algorithm. Both of these methods need a motor on camera to control the focal length. In this thesis, we propose a new method applying to TI DM368 to detect out-of-focus situation without searching algorithm but only using some mathematical features on focus values. | en |
| dc.description.provenance | Made available in DSpace on 2021-06-17T00:13:50Z (GMT). No. of bitstreams: 1 ntu-101-R99922094-1.pdf: 3674035 bytes, checksum: 5013a44a8a67d64929143566c8ebed78 (MD5) Previous issue date: 2012 | en |
| dc.description.tableofcontents | 誌謝 i
口試委員會審定書 ii 中文摘要 iii ABSTRACT iv CONTENTS v LIST OF FIGURES vii LIST OF TABLES x Chapter 1 Introduction 1 1.1 Focus and Focal Length 2 1.2 Auto Focus 3 1.2.1 Active Auto Focus 4 1.2.2 Passive Auto Focus 5 1.3 Focus Value 5 Chapter 2 Related Works 7 2.1 Auto Focus 7 2.1.1 Active Auto Focus 7 2.1.2 Passive Auto Focus 9 2.1.2.1 Phase Detection 9 2.1.2.2 Contrast Detection 11 2.2 Focus Value 16 2.2.1 Gray Level Domain 17 2.2.1.1 Gray Level Energy 17 2.2.1.2 Gray Level Amplitude 18 2.2.1.3 Gray Level Variance 18 2.2.1.4 Sum Modulus Difference 19 2.2.1.5 Adaptive Threshold 19 2.2.1.6 Histogram Entropy 20 2.2.1.7 Tenengrad Filter 20 2.2.1.8 Laplacian Filter 21 2.2.2 Frequency Domain 22 2.2.2.1 Fast Fourier Transform 23 2.2.2.2 Huffman Code Length 24 Chapter 3 Experiment Environment 25 3.1 ARM Subsystem 26 3.2 Video Processing Subsystem 27 3.2.1 Image Sensor Interface 28 3.2.2 Image Pipe 28 3.2.3 Image Pipe Interface 29 3.2.4 Hardware 3A 29 3.2.4.1 Auto Focus Algorithm 30 Chapter 4 Proposed Method 33 4.1 TI DM368 Focus Value 33 4.2 Focus Ratio 34 4.3 Curve Extension 40 Chapter 5 Experimental Results 43 Chapter 6 Conclusion and Future Work 75 REFERENCE 76 | |
| dc.language.iso | en | |
| dc.subject | 焦點特徵值 | zh_TW |
| dc.subject | 監視攝影機 | zh_TW |
| dc.subject | DM368 | zh_TW |
| dc.subject | surveillance camera | en |
| dc.subject | focus value | en |
| dc.subject | DM368 | en |
| dc.title | 監視攝影機的失焦偵測 | zh_TW |
| dc.title | Out-of-focus Detection on Surveillance Camera | en |
| dc.type | Thesis | |
| dc.date.schoolyear | 100-2 | |
| dc.description.degree | 碩士 | |
| dc.contributor.oralexamcommittee | 李傑仁,林合泉 | |
| dc.subject.keyword | 監視攝影機,焦點特徵值,DM368, | zh_TW |
| dc.subject.keyword | surveillance camera,focus value,DM368, | en |
| dc.relation.page | 77 | |
| dc.rights.note | 有償授權 | |
| dc.date.accepted | 2012-07-09 | |
| dc.contributor.author-college | 電機資訊學院 | zh_TW |
| dc.contributor.author-dept | 資訊工程學研究所 | zh_TW |
| 顯示於系所單位： | 資訊工程學系 | |
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| ntu-101-1.pdf 未授權公開取用 | 3.59 MB | Adobe PDF |
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