Free online DAV to M4A converter

What the DAV format is

DAV is a proprietary surveillance recording format used primarily by Dahua DVRs, NVRs, IP cameras, and their desktop playback software. Recordings copied directly from a Dahua device often use the .dav extension and may contain video, audio, timestamps, encryption, or device-specific metadata.

Standard media players and FFmpeg may not decode every DAV variant. Dahua Smart Player is usually the most reliable first step because it can authenticate, play, and export recordings from compatible devices.

What the M4A format is

M4A is an MPEG-4 audio container normally used for AAC audio and, less commonly, Apple Lossless Audio Codec (ALAC). It is supported by phones, browsers, music applications, podcast tools, and most audio editors.

M4A is suitable when you need the audio from a surveillance recording without retaining the camera video. AAC provides smaller files than uncompressed PCM at comparable listening quality, but converting to AAC cannot improve audio that was already compressed in the DAV source.

How to convert DAV to M4A

Method 1: Export with Dahua Smart Player, then use FFmpeg

1. Open the recording in Dahua Smart Player and confirm that audible sound is present.
2. Use the program's export or conversion function, commonly found under File → Convert or a similar recording menu, and save an intermediate .mp4 or .avi file. Menu names vary by Smart Player version.
3. Install FFmpeg and run this command on the exported file:
   ffmpeg -i exported.mp4 -vn -c:a aac -b:a 128k output.m4a

-vn removes the video. The AAC bitrate can be changed to 96k for speech, 128k for typical surveillance audio, or 192k for higher-quality source audio.

If the intermediate file already contains AAC audio, you can avoid another lossy encode with:

ffmpeg -i exported.mp4 -vn -c:a copy output.m4a

Use stream copying only when the audio codec is compatible with the M4A container. If FFmpeg reports an incompatible codec, use the AAC re-encoding command instead.

Method 2: Convert without installing software

You can use the free converter on 101convert.com if the service accepts your particular DAV file. Upload the recording, select M4A as the output, start the conversion, and download the result. DAV files containing proprietary encryption or unsupported audio codecs may fail; export the recording through Dahua Smart Player first, then convert the exported file.

Quality and compatibility limits

• Check that the original DAV has an audio track. Many cameras record video without audio, and an M4A cannot be created from absent audio.
• Surveillance audio may use G.711, G.726, AAC, or another device-specific codec. Re-encoding to AAC is often required because those codecs are not all valid inside an M4A container.
• Exporting through Smart Player can preserve the recording's playable audio more reliably than renaming .dav to .m4a; changing the extension does not convert the data.
• M4A normally carries audio but not surveillance overlays, camera timestamps, motion events, or evidentiary metadata. Keep the original DAV and exported video when those details are required.