WMV to MP4

Convert a Windows Media Video (WMV, usually WMV3/VC-1) to MP4. No browser decodes that codec through WebCodecs, so this runs through a 32MB ffmpeg engine you download once, after you consent, from this site.

WMV to MP4 turns a Windows Media Video file, most often carrying WMV3 or VC-1, into a real MP4. WebCodecs offers no decoder anywhere for that codec, so the file instead goes through a 32MB ffmpeg engine, downloaded once after you tick the consent box on this page. Skip that tick and the file gets refused.

Questions

Why does this need the ffmpeg fallback specifically?

Because WMV usually carries WMV3 or VC-1, a codec no browser decodes through WebCodecs. mediabunny always refuses it, so this page goes straight to the 32MB ffmpeg.wasm engine instead of attempting a browser-native path first.

Is the download automatic?

No. The fallback option defaults to off, and the same consent dialog Convert video uses on its own page appears here, so the 32MB engine downloads only after a person clicks to agree.

Which engine handles this, and where can it run?

ffmpeg.wasm, fetched once from this site after consent, handles both decode and encode for this codec, which mediabunny cannot touch. This is browser only; the command line and MCP refuse it, since neither surface has a way to grant consent.

What size should I expect?

A real re-encoded MP4. The fixture test converts a one-second, 64 by 64 WMV clip to an MP4 of similar duration and resolution, with the status text naming which engine produced it.

What is the reverse page?

There is none. Nothing on this site writes WMV.

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