Description

The common methodology in data embedding is that in the sender side the data that is to be hided is placed with in the pixel values of the cover image producing the stego image. In the receiver side the embedded data in the stego image is retrieved by reversing the same process that is employed for embedding. The data that is to be hided is embedded in the images using pixel pair matching method. A method that embeds the data inside an image with the help of pixel pair matching is proposed. The pixels in the image were divided into blocks the secret image were placed in the blocks identified and the locations were identified as the key for the embedding process. The process reduces the distortions in the stego image and hence the identification of the data in the image is a complicated one. In the preprocessing basic steps like reading image, resizing image and filtering image using any filter is applied. The images were preprocessed using median filter. The median filter is a common filter for all the type of noises occurring in the images and hence median filter is chosen. The secret message were initially converted into matrix format which is known as the embedding sequence. The cover image is divided into blocks. In each blocks the pixels with minimum value is identified. The pixels in the position were replaced by the message sequence. The pixel location is saved as the key value. The process is employed for the whole image. The embedded bits were obtained by reversing the embedding process. The image is divided into small blocks. Using the key obtained the pixels where the message bits were located is identified. From the identified pixel location the embedding sequence is obtained. The embedding sequence is reconstructed into the message. The pixel pair matching process improves the performance of the embedding process. The neighboring pixel points in the images were identified based on the embedding data and they are replaced by the data. For the identification of the neighboring pixels pixel pair matching process is used. The pixel pair matching method identifies the next pixel to be chosen using extraction function and neighborhood selection. The minimum value is calculated such that all the message bits can be embedded. Then, message digits are sequentially concealed into pairs of pixels. The performance of the process is measured with the help of the calculation of the Compression Ratio, PSNR and MSE. The Compression Ratio identifies the capacity of the bits located in the images. The PSNR and the MSE values indicates the similarities between the input and the output image. The measured performance indicates that the proposed system is capable of the hiding the messages with better accuracy and the process is reversible also and hence has numerous applications.