پنهان نگاری وفقی براساس پیچیدگی نسبی پیکسلها در تصاویر دوسطح

In recent years steganography has attracted the attention of many researchers. Steganography can be used in media such as still image, audio, and video. Image is one of the most frequently used media. One of the forms of presentation of an image is halftone. In this paper a method is presented which hides data in halftone images. The data hiding process is performed during the halftoning step. This causes an improvement in security and capacity of the method. Embedding of data in smooth regions of an image may reveal the presence of the hidden data. Therefore, we present a method which analyzes the status of a pixel with respect to its neighboring pixels and hence avoids embedding in smooth regions of the image. Experimental results indicate improvement in the quality of the stego image which increases the security of the embedding.