Steganography on Digital Color Image Using Modulo Function and Pseudo-Random Number Generator

Abstract

In this era, many people exchange data digitally either through the internet or other communication channels. However, data sent digitally can be seen by unauthorized people. Therefore, data security is essential. One of the data security techniques is steganography. This study employs steganography based on Pixel Value Modification (PVM) method using the modulo function. This technique will be implemented to insert a text message in digital images in RGB color space. Besides, we use the Pseudo-Random Number Generator with a secret key to enhance the inserted messages’ security. To measure the performance of the proposed method, testing is carried out by comparing the stego image to cover image based on three criteria, namely imperceptibility, fidelity, and recovery. PVM method using modulo function successfully hides text that the length is less than 200 characters into 255×255-pixel color images. Imperceptibility testing is done by distributing a questionnaire to six people randomly. The results showed that all respondents answered that each test image's stego image and cover image had no difference. At the same time, the results of the fidelity test show that the MSE value is close to zero, and the PSNR value is above 40 dB. Furthermore, recovery testing will check whether the extracted message is the same as the secret message inserted in the cover image. The results showed that all messages inserted were extracted correctly for recovery criteria if given the correct secret key.