A New Pixels Flipping Method for Huge Watermarking Capacity of the Invoice Font Image

Figure 3

Classification of the five different locations: the green point is the pixel to be interpolated. Letters , , , and represented by red circles are four pixels around . (a) Four white pixels around; (b) three white pixels around; (c) and (d) two white pixels and two black ones around; (e) one white pixel and three black ones around; (f) four black pixels around.

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(b)

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