Video Steganography Using Two-Level SWT and SVD

Introduction

Video steganography changes the digital data in the video in a manner that only the sending person and the corresponding receiving person can recognize the message. The below equation gives a description of steganographic processcover_video + text data + stego_key = stego_video(1) where cover_video is a video file which is used to embed the text data with stego_key values. The output is stego_video. The appearance of stego_video is same as the cover_video. The embedded text data doesn't make the distortion in cover video. (Shivani Khosla, & Paramjeet Kaur, 2014)

Any video file format can be used as a cover video in steganography. But that video file has high degree quality and redundancy. If the redundant bits of the video can be changed then there is no change detected in the video. Video files are suitable for to embed the confidential information. The categories of steganography are shown in Figure 1.

The text staganography method was to conceal a confidential message in every nth letter of every word of a text message (Shivani Khosla, & Paramjeet Kaur, 2014). Digital video contains a set of images(frames). These frames are passed sequentially based on the video standards that constitute a video. In video steganography, each letter in text message is embedded in every frame of the video. This process is very difficult to identify the hidden message in stego video.

Figure 1.

Categories of Steganography

Now a days secured data transmission plays an important role in data communication. Secured data main aim is to protect the data from the demolition forces and data hackers. In order to protect the data on public channels, secured data transmission is needed. There are so many secured techniques are available to transmit the data from source to destination like digital watermarking, audio steganography, video steganography, etc,.

Video stegnography is a promising technique to achieve the secured data transmission from source to destination. Steganography is a greek word, it means “covered writing” or “concealed writing”. Video steganography changes the digital data in the video in a manner that only the sending person and the corresponding receiving person can recognize the message. Steganalysis means that discern the concealed message. The main aim of steganalysis is to meet if an algorithm can determine whether a given video contains confidential information. The confidential information can be hidden into video in a manner that cannot be detectable.

Video steganography is nothing but to hide the text data into video. In video steganography, text data act as a secret message and video act as a cover to the secret message. In this paper, text data is encrypted in cover video file using SWT and SVD techniques. SWT is one of the wavelet transformation techniques. It converts the spatial domain into frequency domain. SWT also provides the edge enhancement to an image. SVD of an image can be factored into its three components.