VOB to VOX Converter

Extract VOB DVD audio as Dialogic VOX ADPCM format online

Drop files here. 1 GB maximum file size or Sign Up
to
Facebook Amazon Microsoft Tesla Nestle Walmart L'Oreal

DVD to Phone Audio

Extract voice from VOB DVD files and compress as VOX ADPCM — ready for Dialogic IVR platforms and telephony prompt systems.

Highly Compressed

VOX ADPCM at 4 bits per sample keeps files tiny. Transform DVD-quality audio into compact telephony prompts instantly.

Secure Processing

VOB uploads are removed after conversion. VOX output files are deleted within 24 hours — your audio content stays private.

How to convert VOB to VOX

1

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

2

Choose vox or any other format you need as a result (more than 200 formats supported)

3

Let the file convert and you can download your vox file right afterwards

About formats

VOB (Video Object) is the primary container format used on DVD-Video discs, defined as part of the DVD specification developed by the DVD Forum. The format first appeared with the DVD standard finalized in September 1996 and has since been used on billions of DVD discs produced worldwide. VOB files are based on the MPEG-2 program stream format, containing multiplexed MPEG-2 video alongside audio in AC-3 (Dolby Digital), DTS, MPEG-1 Layer II, or LPCM formats. Beyond audio and video, VOB files also carry DVD subtitle streams as bitmap overlays, navigation data for menu interaction, and chapter point information. The files reside in the VIDEO_TS directory on a DVD disc, with naming conventions (VTS_01_1.VOB, etc.) reflecting the title and part structure of the content. Individual VOB files are limited to approximately 1 GB to accommodate the UDF file system requirements, with longer content spanning multiple files seamlessly. The format supports both NTSC (720x480) and PAL (720x576) video resolutions at bit rates up to 9.8 Mbps for combined audio and video. Integration of video, multi-track audio, subtitles, and navigation into a single program stream made VOB a complete solution for consumer movie delivery. While streaming and newer disc formats have supplanted DVD for new content, VOB remains hugely relevant for accessing the vast library of existing DVD content.
Developer: DVD Forum
Initial release: September 1996
VOX is a headerless audio format built around Dialogic ADPCM encoding, widely adopted in telephony, interactive voice response (IVR) systems, and voice mail platforms since the 1980s. Each audio sample is compressed into 4 bits using an algorithm developed by Oki Electric and implemented in hardware on Dialogic Corporation's telephony interface cards. VOX files typically use a sampling rate of 6000 or 8000 Hz, producing extremely compact recordings optimized for speech intelligibility rather than musical fidelity. Because the format carries no header, playback software must know the sample rate and encoding parameters in advance — a trade-off that reduces overhead but demands careful file management. The primary advantage of VOX is storage efficiency: a one-minute voice recording at 8 kHz occupies roughly 240 KB, making it practical for systems storing thousands of prompts. Dialogic ADPCM conforms to the ITU-T G.726 standard, ensuring interoperability across telephony equipment from different vendors. Even as modern call centers migrate to IP-based systems with codecs like Opus), vast libraries of VOX recordings persist in legacy IVR deployments and compliance archives worldwide.
Initial release: 1983

Frequently Asked Questions

Why convert VOB to VOX?

VOX is the Dialogic ADPCM standard for IVR and telephony. DVD VOB dialogue can be compressed into space-efficient phone system prompts.

How compact is VOX audio?

VOX uses 4-bit ADPCM for roughly 4:1 compression. DVD audio shrinks to tiny telephony files — efficient for prompt storage.

Does VOX have file headers?

No — VOX is headerless raw ADPCM. The telephony system must know the sample rate (typically 8kHz) when loading VOX files.

Will DVD voice quality survive?

VOX handles speech well. Dialogue from DVD VOB sounds clear on phone systems, though music quality is significantly reduced.

Can I convert entire DVDs?

Upload multiple VOB chapters and batch-convert them to VOX. Create a complete telephony prompt library from DVD audio.