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Evaluation of conventional digital camera scenes for Thematic Information Extraction
Data Analysis And Result The size of the airborne colour digital images used in this study of the Merbok River estuary, Kedah is 1200 pixels by 1792 lines namely Area A, Area B and Area C (Figure 2). Three supervised classification methods were performed to the digital images (Maximum Likelihood, Minimum Distance-to-Mean, and Parallelepiped). Training sites were needed for supervised classification and selected based on the colour in present study. The digital image was classified into 4 classes, such as water, forest, land and urban. Accuracy assessment was done in this study to compute the probability of error for the classified map. A total of 200 samples were chosen randomly for the accuracy assessment. Many methods of accuracy assessment have been discussed in remote sensing literatures. Three measures of accuracy were tested in this study, namely overall accuracy, error matrix and Kappa coefficient. In thematic mapping from remotely sensed data, the term accuracy is used typically to express the degree of ‘correctness’ of a map or classification (Foody, 2002). Figure 3 shows the flow chart for data processing of the images.  Figure 2: Digital images used in image classification  Figure 2: Digital images used in image classification  Figure 3: Flow chart for data processing of the images |