Embedding secret information into a dithered multi-level image

A coding scheme for secretly embedding character information into a dithered multilevel image is presented. This scheme inputs both a monotone image and secret information, which is converted to binary sequences, and it outputs a single dithered image. This image contains the character data of about 2 kByte in a dithered bilevel image 3 kByte in a dithered three-level image of 256*256 pixels, and it appears to be an ordinary dithered image. This scheme is available for storing a picture in a database or communication system with secret information.<
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