What is VOB?
Complete guide to the VOB file format
What is it?
VOB (Video Object) is the container format used on standard DVD-Video discs. VOB files are stored in the VIDEO_TS folder of a DVD and contain the actual video, audio, subtitles, and navigation data for the disc. Introduced with the DVD specification in 1996, VOB uses MPEG-2 video encoding and supports Dolby Digital (AC-3) and DTS audio tracks along with subtitle streams.
A typical DVD movie is split into multiple VOB files, each limited to approximately 1 GB to comply with the DVD filesystem (UDF/ISO 9660) specifications. The first file (VIDEO_TS.VOB) contains menu data, while numbered files like VTS_01_1.VOB, VTS_01_2.VOB contain the main feature film. VOB files are closely related to MPEG-2 Program Streams and can often be played directly by media players that support DVD video.
Technical Specifications
Pros & Cons
Advantages
Required format for all commercially produced and consumer-authored DVD-Video discs.
Supports multiple audio tracks (different languages) and subtitle streams in a single file.
Most media players including VLC can play VOB files directly without special configuration.
Contains navigation data for DVD chapter selection and interactive menus.
Disadvantages
VOB is specifically tied to the DVD standard and has no use outside of DVD authoring and playback.
The DVD specification supports up to 720x576 (PAL) or 720x480 (NTSC) resolution, not HD.
MPEG-2 video is far less efficient than modern codecs, producing much larger files than necessary.
Commercial DVD VOB files are encrypted with CSS (Content Scramble System), requiring authorized playback.
When to Use It
Here are the most common situations where VOB is the right choice:
DVD Playback
VOB files are what DVD players and computer drives read when you play a DVD movie.
DVD Backup
Creating a backup copy of a DVD disc involves copying the VOB files to your hard drive.
Format Conversion
Convert VOB files to MP4 or MKV to play DVD content on modern devices without a disc drive.
DVD Authoring
When creating a DVD-Video disc, your authoring software produces VOB files as the output.
Convert Your Files Online - Free
Our free online converter supports all major formats. No software to install, no registration required.
Start Converting NowFrequently Asked Questions
Can I play VOB files without a DVD?
Yes. VLC Media Player and most media players can open and play VOB files directly from your hard drive.
How do I convert VOB to MP4?
Use our free online converter to convert VOB files to MP4, MKV, or other modern formats. This also reduces the file size significantly through better compression.
Why are DVD VOB files split into multiple files?
The DVD filesystem requires individual files to be no larger than approximately 1 GB. A two-hour movie is spread across several numbered VOB files that play back sequentially.
Are VOB files encrypted?
VOB files on commercial DVDs are encrypted with CSS to prevent unauthorized copying. Personal DVD backups and home-made DVDs are not encrypted.
What is the difference between VOB and MPEG?
VOB is a superset of the MPEG-2 Program Stream format with additional DVD-specific data like subtitle streams, multi-channel audio, and navigation packets. A VOB file can often be renamed to .mpg and played as a standard MPEG file.