Evaluating the Suitability of Color Spaces for Image Steganography and Its Application in Wireless Capsule Endoscopy

Image steganography is the art of concealing sensitive information inside cover images. Most of the existing steganographic algorithms use correlated color space such as RGB, where changes to one channel degrade the quality of stego-images due to its strong correlation, thereby making them less suitable for steganography. In this paper, we investigate the suitability of both correlated and uncorrelated color spaces for steganography considering time complexity and image quality. Based on this evaluation criteria, we suggest HSV as the most suitable color space for steganography among the four color models including RGB, YCbCr, HSI, and Lab. Furthermore, we propose an imperceptible steganographic method using the chosen color space based on block-wise magic least significant bit substitution which achieves balance between the time complexity and image quality. Our preliminary experimental results not only validate the superiority of the proposed method in terms of computational complexity and image quality but also suggest its potential application for secure transmission of key frames generated during wireless capsule endoscopy.