Can You Mux Dolby TrueHD or DTS-HD MA into a VOB?

High-resolution audio formats such as Dolby TrueHD and DTS-HD Master Audio cannot be muxed into a standard DVD Video Object (VOB) file. The VOB container is strictly governed by the legacy DVD-Video specification, which limits maximum data bitrates and lacks stream identifiers for modern lossless codecs. This guide explains why the VOB format cannot handle these high-definition audio streams, the specifications that restrict them, and the alternative formats you should use instead.

The DVD-Video Specification Limits

The VOB container is a specialized subset of the MPEG-2 Program Stream format designed specifically for standard-definition DVD-Video discs. Because the standard was finalized in the mid-1990s, the DVD Forum only defined specific, lower-bitrate audio formats to ensure hardware compatibility with standalone DVD players.

A standard DVD-Video VOB strictly supports only the following audio formats:

• Dolby Digital (AC-3): Up to 5.1 channels at a maximum bitrate of 448 kbps.
• DTS (Digital Theater Systems): Standard core DTS only, up to 5.1 channels at a maximum of 1509 kbps (half-rate 754 kbps or full-rate 1509 kbps).
• Linear PCM (LPCM): Uncompressed audio up to 24-bit/96 kHz (stereo) or 16-bit/48 kHz (up to 8 channels), with strict bitrate constraints.
• MPEG-1 Audio Layer II (MP2): Primarily used in PAL territories for stereo or multichannel audio.

High-resolution audio codecs like Dolby TrueHD (based on MLP) and DTS-HD MA were developed a decade later for high-definition optical media (Blu-ray and HD DVD). Consequently, there are no valid Stream IDs defined within the DVD-Video VOB specification to signal or decode these streams.

Bitrate and Buffer Constraints

Even if a custom multiplexer forcefully injected raw TrueHD or DTS-HD MA bitstreams into a .vob extension, the resulting file would violate the multiplexing rules of standard VOB:

1. Total Multiplex Rate: The maximum total combined bitrate (audio, video, subtitles, and system overhead) for a compliant DVD-Video title set is 10.08 Mbps. Dolby TrueHD and DTS-HD MA streams routinely peak anywhere between 6 Mbps and 24 Mbps on their own, quickly exceeding the total system bandwidth allowed for a standard VOB.
2. Buffer Underflows: VOB streams rely on specific buffer models (Video Buffer Verifier and System Target Decoder). Variable bitrates reaching lossless peaks would cause massive buffer underflows in any hardware or software player expecting standard VOB timing.

The Difference Between VOB and EVO

During the format war between Blu-ray and HD DVD, HD DVD introduced the EVO (Enhanced Video Object) container. EVO was a modified MPEG-2 Program Stream capable of containing modern codecs like VC-1, H.264, Dolby Digital Plus, and Dolby TrueHD. While EVO files share structural similarities with VOB files, standard DVD VOB files do not share this capability and cannot decode or parse these packets.

What Happens to DTS-HD MA in a VOB?

DTS-HD Master Audio is structured as a backward-compatible format consisting of a legacy "core" DTS stream alongside a lossless extension stream.

If you attempt to author a DVD or mux a DTS-HD MA track into a standard VOB using DVD-authoring software, the tool will automatically strip the lossless extension stream. It will extract only the lossy 1.5 Mbps DTS core and discard the high-resolution data to conform to the standard DVD VOB structure. Dolby TrueHD does not share this embedded core architecture and must be paired with an entirely separate AC-3 track for legacy playback.

Recommended Modern Containers

To preserve high-resolution audio alongside your video without transcode degradation, you must use modern media containers instead of VOB:

• Matroska (MKV): The most flexible container for home theater playback. MKV natively supports Dolby TrueHD (including Dolby Atmos metadata) and DTS-HD Master Audio (including DTS:X).
• M2TS (MPEG-2 Transport Stream): The container format used by Blu-ray discs. It is natively designed to handle high-bitrate video paired with TrueHD or DTS-HD MA.
• MP4: While primarily used for web distribution and widely compatible with streaming devices, MP4 has added support for Dolby TrueHD and Dolby Digital Plus, though software and hardware support varies more widely than with MKV.