RMVB to VOX Converter

Extract Dialogic VOX audio from RealMedia RMVB video

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Specialized Format

VOX serves IVR phone systems — extract compatible audio directly from RealMedia RMVB video.

Cloud Processing

No specialized software needed. Extract VOX from RMVB entirely through your browser.

Secure Handling

RMVB uploads are deleted after extraction. VOX files are removed within 24 hours.

How to convert RMVB 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

RMVB (RealMedia Variable Bitrate) is an enhanced version of the RealMedia container format developed by RealNetworks, introduced around 2003. While the original RM format used constant bit rate encoding, RMVB employs variable bit rate compression that dynamically allocates more data to complex scenes with high motion and detail, and fewer bits to simpler passages like static shots or fade transitions. This approach yields significantly better visual quality at equivalent average file sizes compared to the constant bit rate predecessor. RMVB gained particular popularity in East and Southeast Asian markets during the mid-2000s, becoming a widely used format for distributing full-length movies and television content in regions where bandwidth was limited but viewers still demanded reasonable picture quality. The format typically uses RealVideo 9 or RealVideo 10 codecs, which drew on technologies comparable to H.264 in their compression approach. RMVB files support embedded subtitle streams and multiple audio tracks, making them practical for multilingual content distribution. The container retains the streaming-friendly architecture of RealMedia while delivering the quality improvements that variable bit rate encoding provides. Although RMVB has been superseded by MP4 with H.264 and other modern formats for most purposes, it retains a user base in Asian markets and can still be found in online media archives and personal video collections from the mid-2000s era.
Developer: RealNetworks
Initial release: 2003
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 extract VOX from RMVB?

VOX is used for IVR phone systems. Extracting from RMVB provides audio in this specialized format.

What software handles VOX?

SOX and specialized audio tools support VOX for processing, playback, and conversion.

Is VOX widely used?

VOX serves specific IVR phone systems needs — a niche but important format for its target applications.

Will audio quality transfer?

Audio from your RMVB video is accurately converted into VOX format during extraction.

Can I batch extract?

Upload multiple RMVB files and extract VOX audio from each simultaneously.