CAVS to AIFF Converter

Convert CAVS to AIFF: Read This First

A .cavs file is a raw Chinese AVS (AVS1) video elementary stream — by the format's own definition it carries picture only, with no audio track inside it. So if your goal is to pull a soundtrack out of a .cavs and save it as AIFF, there is usually nothing to pull: the resulting AIFF comes out silent or empty. This page is honest about why that happens, shows how the converter behaves, and points you to the file that actually holds your audio.

How to Convert CAVS to AIFF

1. Upload Your CAVS File: Drag and drop your .cavs onto the page, or click "+ Add Files" to choose it from your computer. You can queue several files and process them in one batch with the same settings.
2. Set Audio Channel and Audio Sample Rate: Open "Show All Options" to set Audio Channel (Original, Mono, or Stereo) and Audio Sample Rate (Original, or a fixed rate such as 44100 Hz or 48000 Hz). AIFF is written as uncompressed PCM 16-bit Big Endian by default, so these settings define the output directly — leave both on "Original" to mirror the source.
3. Trim (Optional): Use the Trim control to set a start time and duration if you only want part of the timeline rather than the whole stream.
4. Convert and Download: Click "Convert" and download your AIFF. No sign-up, no watermark.

Walk-through: Why a CAVS File Has No Audio to Extract

The .cavs extension is reserved for a bare AVS1 video bitstream — China's national video-coding standard, defined in GB/T 20090.2-2006 and promulgated in February 2006 by the AVS Working Group (founded June 2002). It is the AVS1-P2 JiZhun (base) profile, a block-based, motion-compensated design broadly comparable to MPEG-2 and H.264, and it is most common in Chinese digital-TV, IPTV, and set-top-box environments. The key word is elementary: an elementary stream holds a single media type on its own — here, just the compressed video frames and sequence headers, nothing else. In AVS broadcast and IPTV pipelines the sound is encoded as a separate stream and joined ("muxed") with the video only when the final container is built. Whether your conversion produces anything depends entirely on what is genuinely inside the file you uploaded:

• A genuine, spec-correct CAVS holds no audio stream at all. The decoder finds nothing to extract, so the AIFF comes out silent or the job returns no usable output. This is expected behaviour, not a fault in the tool — nothing in the settings can create a soundtrack that was never stored in the file.
• A file named .cavs that actually plays with sound is unusual, but if yours does, it is almost certainly a misnamed transport-stream or program-stream capture with the audio muxed in. Quick test: open the file in VLC. If you hear sound, it has audio to extract; if it plays as silent video, it does not.

Common Errors and How to Fix Them

• "My AIFF is silent or zero-length" — The CAVS is a true video-only AVS1 elementary stream, so there is no audio to decode. You need the matching audio that shipped with it — usually a separate stream inside the original broadcast container — and you convert that file to AIFF.
• "The conversion failed or returned no output" — Same root cause: an audio-only target needs an audio stream in the input. Confirm the file plays with sound in a media player before converting.
• "It worked, but I actually wanted the video" — AIFF is an audio-only container, so the picture is discarded by design. To keep the footage, convert to a video format with CAVS to MP4 instead.
• "My player won't open the .cavs to check it first" — Most mainstream players can't decode AVS1-P2; FFmpeg ships an open-source cavs decoder, which is why a server-side converter is the practical route. If it opens but plays silent, that confirms there is no audio to pull.
• "A long source uploads slowly" — A long AVS broadcast capture can be sizeable, and the real wait is upload time over your connection, not anything on your device. Trim to the segment you need before uploading.

When This Doesn't Work

If your file is a real video-only CAVS, no online tool can conjure audio that was never written into it — the data simply isn't there. Your genuine options are to find the separate audio stream that travelled with the AVS video (often AC3 or an MPEG audio file) and convert that with AC3 to AIFF, or to convert the complete muxed broadcast container that carries both streams — a transport stream or program stream — with TS to AIFF or MPG to AIFF. In those files the audio is genuinely present, so it comes through. Note that many "CAVS to AIFF" tools online accept the upload and run the job without warning you that a bare CAVS has no soundtrack — the empty result is the format talking, not the converter.

Frequently Asked Questions

Why is my CAVS to AIFF output silent or empty?

Because .cavs is an AVS1 video elementary stream and holds no audio. A spec-correct CAVS contains only compressed video frames and sequence headers — there is no audio track inside it to decode, so any AIFF produced from a bare .cavs will be silent or empty. In AVS workflows the sound was encoded as a separate stream and muxed in only when the final container was built. Convert that separate audio file — or the muxed transport/program stream — to AIFF instead.

What exactly is a .cavs file?

It is a raw video elementary stream encoded with AVS1 (Audio Video Coding Standard), China's national video-coding standard, defined by GB/T 20090.2-2006 and promulgated in February 2006 by the AVS Working Group (founded June 2002). The picture uses the AVS1-P2 JiZhun (base) profile, broadly comparable to MPEG-2 and H.264. It appears mainly in Chinese digital-TV, IPTV, and set-top-box environments, which is why general-purpose players usually can't open it. Despite the word "Audio" in the standard's name, a bare .cavs carries only video.

Where is the audio that goes with my CAVS file?

In AVS broadcast and IPTV pipelines the audio is kept as its own elementary stream and muxed with the video only at the final packaging step. If you have the original broadcast capture — typically a transport stream (.ts) or program stream (.mpg) — the audio lives there, and you can extract it with TS to AIFF or MPG to AIFF. A standalone AVS audio file is often AC3, which converts with AC3 to AIFF. The bare .cavs on its own has none of that.

How can I tell whether my .cavs actually contains audio?

Play it in a media player such as VLC. If you hear sound, the file is almost certainly a misnamed transport or program stream with muxed audio, and it will convert to AIFF normally. If it plays as silent video, it is a true video-only CAVS and there is nothing to extract. In our testing, files that played silently in VLC produced empty AIFF output every time, while muxed containers that played with sound converted cleanly.

What does AIFF store, and what bit depth does this converter use?

AIFF (Audio Interchange File Format) is Apple's uncompressed, lossless audio container from 1988, built on the EA IFF 85 chunk structure. This converter writes PCM 16-bit Big Endian by default — the same big-endian byte order AIFF has used since its Motorola 68000 origins, and the standard CD-quality 16-bit depth. Because it is uncompressed, the output preserves whatever audio it decodes with zero generational loss, at the cost of larger files — roughly 10 MB per minute for 16-bit/44.1 kHz stereo.

I want the CAVS video, not its (missing) audio — what should I use?

That is a different tool. CAVS to MP4 wraps the AVS1 video into a widely playable MP4 container so it opens in normal players, and the general Video Converter handles other targets. Use this AIFF page only when you have a real audio source — the muxed container or the separate audio stream — rather than a bare video-only .cavs.

How are my files handled, and how long are they kept?

Your file is uploaded over an encrypted connection, processed on our servers, and deleted automatically a few hours after conversion — no sign-up, no watermark, and never shared or made public. The realistic limit on very large broadcast captures is upload time, not anything on your device.