Convert mono to stereo or back

Change an audio file's (or a video's audio track's) channel count: average every channel down to mono, duplicate a mono track into identical left and right channels, or swap left and right, decoded and re-encoded as WAV through the same PCM path as audio-reverse. WAV decodes everywhere; other codecs need a browser.

Convert mono to stereo or back changes a file's channel count: downmix averages every channel into one, duplicate copies a mono channel onto left and right, and swap exchanges them. Duplicate refuses stereo input and swap refuses anything but stereo, so the wrong mode for the file stops with a named error. WAV decodes anywhere; other codecs need a browser.

Questions

What does downmix do?

It averages every channel together into a single mono channel, sample by sample. Mono input passes through unchanged, since there is nothing left to combine.

Why did duplicate mode refuse my file?

Because duplicate only accepts mono input and copies that single channel onto both left and right. A stereo or multichannel file is refused with its channel count named; downmix it first.

What does swap do?

It exchanges the left and right channels of a stereo file. It only accepts exactly two channels and refuses anything else, naming how many channels the file has.

Does this work on a video file?

Yes, on the audio track. The picture is untouched; only the decoded audio samples are remixed and written out as a new WAV file.

Why is the output always WAV?

Because the audio is decoded to raw PCM, remixed sample by sample, and re-encoded through the same path Reverse audio uses, which always writes WAV.

Related Video tools

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