本研究旨在利用CCD攝影機，擷取高解析度近岸影像，透過長時間的拍攝過程，可將影像中特定範圍內之像素陣列組合成時序列資料，並使用像素工具分析法進行分析獲得所需之資訊。本文觀測區域為高雄西子灣海水浴場，主要研究西子灣海域內波浪變化情形，內容可分為三個部分。第一部分為波浪溯升之分析，分析影像中陸地與海水的交界區域，所呈現之影像強度變化差異；第二部分為向離岸流及沿岸流分析，由Chickadel et al.(2003)所提方法，將所獲得時序列像素資訊轉換成速度譜，可計算出向離岸流及沿岸流之平均速度；第三部分則是波速與波向之計算，利用交錯頻譜(cross spectrum)解析在方向陣列上兩個不同位置的像素點，並藉由其相位頻譜計算出波浪由一像素點移動至另一像素點之間的移動時間，進而求出波速與波向資訊。

In this paper, a high resolution CCD camera is used to capture image of nearshore waters, and pixel time series from selected zone in the image is constructed to study the wave and current information. The field study area is located in Hsi-tzu-wan bay of Kaohsiung. The analysis of image data consists of three parts. The first parts focuses on wave run-up. Analysis of intensity difference between beach and sea water is used to capture the contour of swash zone. The second part focuses on onshore-offshore current and longshore current. The computational algorithm was based on Chickadel et al. (2003) which used short time series of image data collected from cross shore and longshore array of pixels. These time series was first Fourier transformed to a frequency-wave number spectrum and, finally, to a velocity spectrum. The third part of this study focuses on wave speed and wave direction. Analysis of travel time of individual breakers is estimated from pairs of separated pixels in the array, via the cross spectrum in the frequency domain, Wave speed and wave direction are computed using travel time and pixel separation.

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