Free online DAV to OPUS converter

Security-camera recordings in DAV format often need conversion when only their audio is required for playback, transcription, messaging, or compact archiving. Because OPUS stores audio rather than video, the DAV recording must contain an audio track and may first need export from the camera manufacturer's software.

What the DAV format is

DAV is a proprietary surveillance-video format used by DVRs, NVRs, and IP cameras from manufacturers such as Dahua and some compatible systems. Recordings commonly contain H.264 or H.265 video, timestamp overlays, motion metadata, and sometimes one or more audio tracks.

DAV files are usually created by the recorder or downloaded through its desktop client. Their codec and container details vary by firmware, so a generic media player or converter may not open every DAV file. Manufacturer software such as Smart Player or the recorder's export function is often needed to verify the recording and convert it to a standard format.

What the OPUS format is

Opus is a lossy audio codec normally stored in an Ogg container with the .opus extension. It supports speech and general audio at bitrates from low-bandwidth voice settings to high-quality stereo, making it suitable for web playback, voice recordings, calls, transcription workflows, and smaller archives.

OPUS cannot preserve the original video, camera overlays, timestamps, or surveillance metadata. It is appropriate only when the audio track is the required output.

How to convert DAV to OPUS

Option 1: export the DAV recording first

1. Open the recording in the camera or DVR manufacturer's playback software.
2. Use Export, Convert, or Save as and choose a standard video format such as MP4 or AVI. Enable audio if the software provides a separate audio-track setting.
3. Check the exported file in a player that can show stream information. If it has no audio stream, an OPUS file cannot be produced from that recording.
4. Convert the exported file with FFmpeg. For a speech-oriented result, use:
   ffmpeg -i recording.mp4 -map 0:a:0 -c:a libopus -b:a 64k recording.opus

The -map 0:a:0 option selects the first audio stream and prevents video from being included. Use -b:a 96k or -b:a 128k for music or higher-quality audio. If the source is already compressed, transcoding cannot restore information that was discarded during the original recording.

Option 2: try direct extraction

If FFmpeg recognizes the DAV container and its audio codec, test it with:

ffmpeg -i recording.dav

If FFmpeg lists an audio stream, convert it directly:

ffmpeg -i recording.dav -map 0:a:0 -c:a libopus -b:a 64k recording.opus

If FFmpeg reports an unknown format, invalid data, or no audio stream, use the recorder's export software first. Do not rename .dav to .opus; changing the extension does not change the encoded data.

For a no-installation option, upload the file to the free converter on 101convert.com, select OPUS, and download the result if the service accepts that particular DAV variant. Large surveillance files, proprietary encryption, and privacy requirements can make local export preferable.

Quality and compatibility limitations

The conversion is normally a two-stage process: DAV video export, followed by audio encoding. The first stage may alter timestamps, remove proprietary metadata, or re-encode the audio before OPUS encoding. Keep the original DAV file when it may be needed as evidence.

Choose a sample rate supported by the source, commonly 8, 16, or 48 kHz. For speech, 32–64 kbps mono is often sufficient; 96–128 kbps is more suitable for general stereo audio. Some older players and editing applications do not support OPUS, so WAV or AAC may be a better compatibility target when OPUS is not specifically required.