VOB is a DVD-based multimedia container video file format developed by the DVD Forum. It is based on MPEG-2. A file with the .VOB extension can have video and audio streams, audio and video data, subtitles, disc menus, and navigation content. And all this is combined into a common stream. In this case, video playback is carried out in MPEG-2 format, and audio in various audio formats. Most often, the AC-3 format is used for this, since it provides the most favorable ratio of bitrate and sound quality. The VOB format has gained popularity as files in which you can store video and sound on DVD discs. As a rule, if they have such an extension, then the files have a place in the VIDEO_TS DVD folder in the DVD root directory. Typically, .VOB format videos are opened using any video player that supports MPEG-2 compression. There are many free players that support the .VOB format. In particular, Zoom Player, Media Player Classic VLC, Media Player, Light Alloy and others. Now popular is the paid player CyberLink PowerDVD, which has rich functionality. He specializes in playing DVD videos. VOB video files, originally called DVD Video Object File, can be accompanied by .IFO and .BUP information files.
MPEG is a special standard for compressing audio files and video files into a different format, which is most convenient for downloading or forwarding, say, over a global network. The specified standard was developed by the Moving Picture Experts Group. It was created by the international organization ISO just in order to develop a standard for the compression and transmission of digital video and audio data. The official designation for this group is ISO / IEC JTC1 / SC29 WG11. The first time she met in Ottawa in May 1988. By 2005, up to 350 people became participants in the meetings. MPEG, that is, Moving Picture Experts Group, consists of 3 components: Audio, Video, System (combining and synchronizing the other two). There are different MPEG standards, which are also called phases: MPEG-1, MPEG-2, MPEG-3, MPEG-4, MPEG-7. According to the MPEG-1 standard, for example, streams of video and audio data are sent at a speed of 150 kilobytes per second. The speed of a single-speed CD-ROM player is similar. Streams are managed by sampling key video frames and filling in areas that change between frames. This standard ensures the quality of the video image is significantly lower compared to the video that is transmitted on the television standard.