OGV to RMVB Converter

OGV to RMVB: Check Your Frame Size Before You Convert

RMVB is RealNetworks' RealMedia Variable Bitrate container — the locally-stored counterpart to the constant-bitrate RealMedia files RealPlayer streamed, and for years the distribution format of choice for Asian film and drama releases. Ogg Video is the Xiph project's open container, normally carrying Theora video and Vorbis audio. Converting one into the other is a legacy-to-legacy move, and there is exactly one thing that decides whether you are happy with the result: the frame size you start with.

The RealVideo encoders on this page are capped at 640 × 480, and how that cap is applied depends on which resolution mode you pick. Get it wrong and a widescreen clip comes back squeezed into a 4:3 frame. The table below is measured output, not theory, so read it first and choose accordingly.

What Your Frame Size Becomes

Every figure here is the actual encoded frame size we got out of a RealVideo stream, checked with a probe on the finished .rmvb:

Three rules produce those numbers. Keep original asks for the source's own dimensions and then clips each axis to 640 and 480 independently, with no aspect correction — which is exactly why a 16:9 source collapses into a 4:3 frame. Preset Resolutions sets the height only and lets the width follow the source's aspect ratio, so the shape survives. And every dimension is floored to a multiple of 16, because RealVideo codes in 16 × 16 macroblocks: that is why 360 lines become 352, and why the 360p preset lands at 624 × 352 rather than 640 × 360.

The practical rule: if your .ogv fits inside 640 × 480, leave Keep original alone. If it is larger, use a preset. Never use a preset to go up — upscaling a 640 × 360 clip to 848 × 480 adds bytes and no detail.

How to Convert OGV to RMVB

1. Upload Your OGV File: Drag the .ogv onto the page or click "Add Files". Several files can be queued and share one set of settings.
2. Set Video resolution first: Video resolution opens on Keep original, with Preset Resolutions, Resolution Percentage, Width, Height and Width x Height alongside. Use the table above to decide. If you enter your own Width x Height, choose multiples of 16 inside 640 × 480 — 640 × 352 rather than 640 × 360 — and you will get precisely what you asked for.
3. Choose a Video Codec and an Audio Codec: Video Codec offers RealVideo 1.0 (RV10), which the page opens on, and RealVideo 2.0 (RV20). Audio Codec lists AAC, AC3 and RealAudio 1.0; pick one explicitly, because two competing rules in the configuration both claim the right to preselect the audio codec on a RealMedia target and neither can be relied on.
4. Convert and Download: Click Convert and save the .rmvb. Files are uploaded over an encrypted connection, re-encoded on our servers, and deleted automatically after a few hours — no sign-up, no watermark.

The Controls That Are Real, and the One That Is Not

Quality Preset is the mode the File Compression panel opens on and the sensible default: on a video source it scales the encode against the source's own bitrate. Specific file size and Constant Bitrate both work if you need a size ceiling. Constant Quality works too, but read the label with suspicion — it says CRF and behaves as a RealVideo quantiser on a 1 to 31 scale where lower is better, the opposite direction from the H.264 sliders the control was named after. Set it deliberately or leave it alone.

Constraint Quality is the one that does nothing here. It works by setting a maximum bitrate together with a buffer size, and both of those arguments are removed from the encode when the output codec is RealVideo 1.0 or 2.0, because those encoders accept only a plain target bitrate or a quantiser. The field renders, it accepts your number, and the number never reaches the encoder. Use Constant Bitrate or Specific file size instead.

One more ceiling worth knowing: the RealMedia muxer limits each frame to roughly 64 KB, so the pipeline caps the video bitrate at a value derived from that limit and the source frame rate — on the order of 4 to 5 Mbit/s at ordinary frame rates. On a mobile- or SD-sized clip you will never approach it.

Ogg Video and RealMedia: Two Different Ways to Lose Browser Support

Neither format plays in a current browser, so if browser playback is your goal this conversion does not get you there. OGV to MP4 does.

Frequently Asked Questions

Why did my widescreen clip come out looking squashed?

Because you left Video resolution on Keep original and the source was wider than 640 pixels or taller than 480. In that mode the converter asks for the source's exact dimensions and each axis is then clipped to the ceiling separately, so 1280 × 720 becomes 640 × 480 and everything in frame gets narrower. Switch to Preset Resolutions and pick 480p: we measured 1920 × 1080 and 1280 × 720 sources both landing at 848 × 480 with the correct shape.

Why is my output 352 pixels tall when the source was 360?

Macroblock alignment. RealVideo codes in 16 × 16 blocks, so both dimensions are floored to a multiple of 16 before encoding, and 360 is not one — it drops to 352. We saw exactly this converting a 640 × 360 .ogv, which came back 640 × 352. It is a crop of eight lines, not a stretch, so nothing is distorted; if you need an exact number, enter Width x Height values that are already multiples of 16.

Should I pick RealVideo 1.0 or RealVideo 2.0?

RealVideo 2.0 for anything but a period-correct target. RealVideo 1.0 is what the page opens on and is fine for small frames, but its encoder refuses frames of 4,096 macroblocks or more — about one megapixel — and simply fails to open rather than downscaling for you. We confirmed that boundary directly: at 1024 × 1024 the RealVideo 1.0 encoder produced no file at all, while RealVideo 2.0 accepted the same frame size. Inside the 640 × 480 ceiling this cannot bite, but it is one more reason to prefer the later codec.

Which audio codec should I choose?

Choose one rather than accepting whatever appears. AAC is right for anything you will play on a computer and handles music and speech alike. AC3 is worth it only if the destination is a receiver expecting Dolby Digital. RealAudio 1.0 is a narrowband speech codec that lands at 8 kHz mono no matter what the source carried, which is correct for a period RealPlayer target and ruinous for music. We confirmed all three mux into the container successfully.

What is the difference between RMVB and RM?

The container is the same and the label describes the encoding strategy. RealMedia was built around constant-bitrate streaming, where a fixed rate matters because the file is being delivered over a connection of known bandwidth. RMVB was introduced for files stored locally, where a variable bitrate can spend more bits on complex scenes and fewer on simple ones for the same overall size. Reading the bytes confirms it: our .rmvb output begins with the same .RMF signature a .rm does. If you want the older extension, OGV to RM writes it.

Will the picture look better than the original Theora?

No. This is a lossy re-encode into a codec family that is older and weaker than Theora, so the realistic outcome is "the same picture or worse, in a container a RealPlayer-era target will accept". The encoder also spends part of its budget faithfully reproducing whatever artifacts Theora already introduced. If picture quality is what you care about, keep the .ogv and convert to OGV to MP4 instead.

Why won't my OGV play in my browser?

Because no current browser decodes Theora. Chrome disabled it by default in version 120 and Chromium removed it in 123; Firefox disabled it by default in version 126; Safari never shipped it. The file is fine — VLC and mpv still play .ogv without trouble, and this converter decodes it server-side. It does mean you cannot scrub the clip in a browser tab to decide where to trim, so check it in a desktop player first.

Does the Vorbis audio get re-encoded even though it was already compressed?

Yes. There is no pass-through path on this conversion: RealMedia cannot hold a Vorbis stream, so the audio is decoded and compressed again into whichever codec you chose, and the video is re-encoded regardless. That is a second lossy generation on both streams. It is unavoidable given the target container, which is one more reason to treat the .rmvb as a delivery copy and keep the .ogv as your master.

How are my files handled while they are on your servers?

Your .ogv is uploaded over an encrypted connection, decoded and re-encoded on our servers, and both the upload and the resulting .rmvb are deleted automatically after a few hours. Files are never shared or made public, there is no watermark, and no account is needed. Because the processing runs server-side, the practical constraint on a long clip is upload size and time rather than anything about your own machine.