DivX to AU Converter

DivX to AU Converter

DivX is an MPEG-4 Part 2 (ASP) video format — usually an AVI container carrying compressed video plus an MP3 or AC3 audio track. AU is the Sun/NeXT audio format (.au, sometimes .snd), a legacy Unix and Java sound container that typically holds uncompressed big-endian PCM or µ-law samples. This converter discards the video and writes the DivX audio track out as a standalone AU file — useful when an old Unix toolchain, a Java sun.audio player, or a legacy embedded system expects .au specifically.

DivX Format at a Glance

AU Format at a Glance

How to Convert DivX to AU

1. Upload Your DivX File: Drag and drop your .divx (or DivX-encoded AVI) onto the page, or click "Add Files" to pick it from your computer. Add several files to extract them in one batch.
2. Set Audio Sample Rate: Leave it on "Original" to keep the source rate, or pick a value (for example 8000 Hz to mimic classic µ-law AU, or 44100 Hz for CD-rate audio).
3. Set Audio Channel and Trim (Optional): Choose "Original", mono, or stereo under Audio Channel, and use the Trim controls if you only need a clip of the audio.
4. Convert and Download: Click Convert and download your .au file. Files upload over an encrypted connection, are processed on our servers, and are deleted automatically after a few hours. No sign-up, no watermark.

Frequently Asked Questions

What is an AU file and what opens it?

AU (.au or .snd) is the Sun/NeXT audio format. It plays in cross-platform tools like VLC and Audacity, in older Unix audio utilities, and in Java programs through the sun.audio/javax.sound APIs. Most consumer media players and phones do not handle .au natively, which is why it is a legacy/niche choice rather than an everyday audio format.

Will converting DivX to AU improve the audio quality?

No. The audio inside a DivX file is almost always MP3 or AC3, which are lossy. Decoding that to uncompressed PCM AU produces a larger file but cannot restore detail the lossy codec already discarded. AU is the right pick only when something specifically requires the .au container — not as a quality upgrade.

Why is my AU file so much larger than the DivX?

Because the default AU encoding here is uncompressed PCM (16-bit big-endian). A 128 kbps MP3 track expands to roughly 1.4 Mbps as 16-bit/44.1 kHz stereo PCM — about ten times the bitrate — so the AU output is expected to be several times bigger than the original compressed audio. Choosing µ-law or A-law, or a lower sample rate, keeps the file smaller.

Which encoding does the output AU use?

By default the converter writes PCM 16-bit big-endian, the linear-PCM variant of AU. The classic 8-bit µ-law and A-law encodings (the historical 8000 Hz "Sparc-audio" sound) are also available if you need maximum compatibility with very old Unix players. In our testing, a 60-second stereo DivX audio track at 44100 Hz produced an AU file of roughly 10 MB as 16-bit PCM.

My converted AU file is silent — what happened?

That usually means the source DivX had no audio track, or its audio stream was empty or corrupted. DivX-to-AU only extracts existing audio; it cannot create sound that was never there. Confirm the DivX actually plays with sound first, then re-run the conversion.

Should I use AU or a modern format like MP3?

For anything other than a legacy Unix/Java requirement, MP3 or M4A is the better choice — far smaller files and universal device support. Use DivX to MP3 to pull the audio into a compact, widely playable format instead. If you already have .au files to modernize, AU to MP3 goes the other way.

Is the conversion private?

Yes. Your file is uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours. There is no sign-up, no watermark, and your files are never shared or made public.