RMVB to VOB Converter

RMVB to VOB Converter

RMVB is RealNetworks' RealMedia Variable Bitrate container from 2003 — the format that carried an enormous amount of Asian film, drama and fansub material through the broadband years, precisely because it squeezed a watchable picture into a very small file. VOB is DVD-Video's container: a deliberately constrained subset of the MPEG program stream, defined around a disc specification from 1996 that fixes the codecs, the frame sizes, the audio formats and a hard bitrate ceiling.

Converting one to the other is therefore not a compression job. It is the opposite — you are taking a file built to be small and re-encoding it into a format that has a minimum bitrate, using a codec far less efficient than the one it came from. Expect the output to be several times the size of the input. That is inherent to the target, and the sections below explain exactly where the growth comes from.

RMVB and DVD-Video Compared

How to Convert RMVB to VOB

1. Upload Your RMVB File: Drag the .rmvb onto the page or click "+ Add Files" to browse. Several episodes can be queued together and each converts separately.
2. Confirm the Video Codec and Audio Codec: MPEG-2 is the value the Video Codec list opens on, which is what DVD-Video expects; MPEG-1 is the only alternative. Audio Codec opens on MP2, with AC3 (Dolby Digital), DTS (DCA) and MP3 also listed — read the audio question below before choosing MP3.
3. Set Video resolution, and Trim if Needed: Video resolution opens on "Keep original" and also takes Resolution Percentage, Preset Resolutions, Width, Height and Width x Height. On this codec, resolution is the control that genuinely moves the output, for the reason given two sections down. Trim takes a Start time and a Duration.
4. Convert and Download: Click Convert and download the .vob. Files upload over an encrypted connection, are converted on our servers and are deleted automatically after a few hours — no sign-up, no watermark, never shared or made public.

Why the VOB Comes Out So Much Larger

MPEG-2 has no constant-quality mode — the codec predates CRF entirely — so our encoder substitutes a bitrate calculated from the output frame size whenever a quality-style setting reaches it. That substituted figure is a floor, not a target, and it is applied regardless of how simple or how low-bitrate your source was. A 700 kbit/s RealVideo rip does not stay at 700 kbit/s.

The floor exists because MPEG-2 fails outright if asked to encode a large picture at a small bitrate. The practical consequence for an RMVB source is straightforward arithmetic: a 45-minute episode at 700 kbit/s is roughly 230 MB, and the same episode at the 2 Mbit/s floor is roughly 675 MB before the audio is counted. Keeping the frame size at or below DVD dimensions is the only lever that keeps that number sensible — upscaling a 512x384 rip to 1080p triples the floor for a picture that has no extra detail to show.

What Each File Compression Mode Actually Does

Change Video resolution if you want the output to move. That is the honest summary of this table.

A Single VOB Is Not a DVD

A .vob holds the multiplexed streams, but a set-top player also needs the navigation layer — the VIDEO_TS folder with its .IFO information files and .BUP backups — before it can find a title, let alone show a menu. Desktop media players will often open a lone unencrypted VOB directly; DVD navigation simply is not available when those files are missing.

To get from this file to a disc, load the VOB into DVD authoring software, which builds the folder structure and burns the result. And if what you actually want is a file that plays on phones, TVs and browsers rather than an optical disc, skip VOB entirely — RMVB to MP4 produces a far smaller file with vastly wider support, and it is the conversion most people arriving from an RMVB collection are really looking for.

Frequently Asked Questions

Why is my VOB so much bigger than the RMVB it came from?

Two effects compound. First, MPEG-2 is a 1990s codec and RealVideo RV40 is a considerably more efficient one, so holding the same picture costs MPEG-2 several times as many bits. Second, our encoder applies a resolution-derived bitrate floor, because MPEG-2 fails outright below it — 2 Mbit/s for anything up to standard definition, rising with frame size from there. An RMVB encoded at 700 kbit/s therefore comes out at 2 Mbit/s minimum no matter what you set. The only real lever is keeping the frame size down; the quality controls will not take you below the floor.

Which resolution should I choose for an NTSC or a PAL disc?

Enter it as Width x Height rather than using a preset: 720x480 for NTSC, 720x576 for PAL. The Preset Resolutions list sets the height alone and lets the width follow the source's aspect ratio, so "480p" on a 640x352 rip will not give you 720x480 and an authoring tool will reject the result. DVD-Video also permits 704x480, 352x480 and 352x240 on NTSC, and 704x576, 352x576 and 352x288 on PAL, which are worth considering when a long episode run has to fit on one disc.

Why is MP2 the default audio, and can I use MP3 instead?

MP2 — MPEG-1 Audio Layer II — is preselected because it is one of the four audio formats DVD-Video permits, alongside Dolby Digital (AC-3), DTS and linear PCM, and it plays on every DVD player ever built. MP3 does appear in the dropdown and will mux into the program stream without an error, but it is not a legal DVD-Video audio format: authoring software may reject the file and a set-top player may run it silently. Stay on MP2 for straightforward stereo, or choose AC3 if you want Dolby Digital to match what commercial discs ship with.

What happens to the RealAudio soundtrack?

It is decoded and re-encoded — a DVD program stream has no place for a RealAudio track, and nothing here copies streams through untouched. Most RMVB files carry the Cook codec (RealAudio G2, from 1998), which is already heavily lossy at the low bitrates the format was used at, so the MP2 or AC-3 encode is a second generation on top of that. Choose a generous setting rather than a tight one; there is no point trying to save space on the audio when the video floor dominates the file size anyway.

My RMVB is 512x384 — should I upscale it to 720x480 for the disc?

Set the frame size to a DVD-legal value, yes, but understand what you are buying. Upscaling stretches the pixels that are already there; it does not recover detail the original encode discarded, and the softness of a 2000s RealVideo rip will be more obvious on a television than it ever was on a laptop. What upscaling definitely does is raise the bitrate floor and the file size. Going to 720x480 keeps the floor at 2 Mbit/s, which is the sensible choice; going beyond standard definition for this kind of source is not.

Why does my widescreen rip look the wrong shape?

RMVB rips were frequently encoded at odd, non-standard frame sizes — 640x352, 704x396, 512x288 — that already represent a widescreen picture with square pixels. DVD-Video expects one of its own fixed rasters, and anamorphic widescreen on a disc means storing a 16:9 image inside a 720x480 or 720x576 grid with non-square pixels. Resizing here normalises pixels to square without applying that stretch, so set the display geometry you want explicitly under Width x Height, and set the display-aspect flag in your authoring software when you build the disc.

Why does one RMVB convert and another fail immediately?

The usual cause is DRM. Some commercially distributed RealMedia files carry RealNetworks Helix protection, which blocks decoding in any tool, converter or player alike. Unprotected files convert normally, so a file that still fails is more often corrupted or only partially downloaded — check that it plays end to end in VLC first, and if it does not, re-save a clean copy before uploading. Decoding here runs on the FFmpeg lineage, whose decoder table covers the RealVideo and RealAudio families, which is why files Windows Media Player rejects still convert without RealPlayer installed.

Does the converter deinterlace, or fix combing in an old TV rip?

No. There is no deinterlacing filter anywhere in this pipeline, under any setting, so if your RMVB was ripped from an interlaced broadcast without deinterlacing at the time, the woven fields are decoded and re-encoded exactly as they are. Combing is preserved into the VOB. That said, DVD-Video was designed around interlaced standard-definition television, so an interlaced source is not itself a problem for a disc — it is only a problem if you were hoping this step would clean it up.

Can I turn the VOB back into an ordinary video file afterwards?

Yes. VOB to MP4 re-encodes a DVD stream into H.264 for phones, browsers and smart TVs. Bear in mind that round-tripping RMVB to VOB and back adds two generations of lossy encoding to a source that was already lossy, and the MPEG-2 stage in the middle throws away detail that the H.264 pass cannot recover. If a modern file is the eventual destination, convert straight there instead: RMVB to MP4 is one generation rather than three.

How are my files handled during the conversion?

Files travel over an encrypted connection, are converted on our servers, and both the upload and the finished .vob are deleted automatically after a few hours. There is no sign-up, no watermark, and nothing is shared or made public. Because the encoding happens on our side, the practical constraint is upload size and connection speed rather than anything on your own machine — and RMVB files are small by nature, so uploads are usually quick even for feature-length material. If you only need one scene, the video cutter accepts .rmvb directly.