As a result of the continuously increasing amount of important data, the demand for information security increases daily. Steganographic techniques can play a considerable role in solving this issue, since they can hide the necessary data. Generally, audio and image files have been utilized as hiding media in this area. However, because of their limited capacity, these media limit the amount of hidden information. On the other hand, the capacity limit can be exceeded by applying steganography on video files. There are few studies on video steganography in the literature. In this study, a steganographic library, which is independent of medium and method, was developed for hiding information in audio, image, and video files by using various methods. Furthermore, distinctly from other studies, the lattice approach was proposed for this issue. In this approach, security was increased by using the image and audio domain of video together in the hiding process. In addition, we were able to hide the real-time data in a video taken from a webcam. Thus, the size of the produced video file could be set, according to the size of the secret file, with this model. Meanwhile, the possibility of detecting the existence of steganography by comparing to the original video was limited. The success of the hiding process was also evaluated with various steganalyses and noise measurement methods, and the results are presented and discussed in the relevant sections.