Video steganography algorithm based on motion vector of moving object

摘要

Video steganography is a knowledge that provides a secure connection by hiding the secret message in the video sequins. In this paper, we propose a new video steganography algorithm based on object motion which the secret information is embedded in motion vectors of moving objects. Therefore by using the mean shift algorithm the existed objects in each frame are detected. Based on motion estimation algorithm in B and P frames, motion vectors of each object with quarter pixel accuracy are extracted. To ensure that the selected motion vectors are belong to the object and also have a desire balance between capacity and video quality, a threshold value is defined. So the motion vectors whose value are greater than the threshold value are selected. The secret message is embedded in one-quarter both horizontal and vertical component of each selected motion vector. The result shows that the proposed algorithm can embed a large amount data in motion object and achieved a good video quality.