Free online DAV to MTS converter

Security DVRs and NVRs often save camera footage as DAV, while video editors and AVCHD-compatible devices commonly expect MTS. Converting the recording lets you use standard MPEG transport-stream workflows, but proprietary DAV files may require the manufacturer’s playback software before conversion.

What the DAV format is

DAV is a proprietary surveillance-video format used by many digital video recorders and network video recorders, especially systems from manufacturers such as Dahua and some Hikvision product lines. It commonly stores H.264 or H.265 camera video with recorder-specific timestamps, audio, metadata, and sometimes encryption or digital-watermark information.

You usually encounter DAV files after exporting footage from a CCTV recorder, surveillance camera, or vendor management application. A general-purpose media player may not decode them even when the underlying video codec is standard; the recorder’s desktop player, such as Dahua Smart Player or a vendor-specific DAV player, may be required.

What the MTS format is

MTS is an MPEG transport stream file, commonly associated with AVCHD camcorders and Blu-ray-compatible video workflows. It typically contains H.264 video and AC-3 or LPCM audio in a transport stream designed for high-definition recording and playback.

MTS is useful when an editor, authoring program, television, or AVCHD-compatible device specifically accepts transport-stream input. It preserves high-definition video efficiently, but changing the container to MTS does not improve the source resolution, bitrate, or image detail.

How to convert DAV to MTS

Use the recorder’s player when FFmpeg cannot open the file

1. Copy the original DAV file from the recorder and keep it unchanged as a backup.
2. Open it in the manufacturer’s desktop player. If the file came from a Dahua system, try Smart Player; for other systems, use the player supplied with the recorder or its export utility.
3. Use Export, Convert, or Save as and select a standard intermediate format such as MP4 or AVI. Select the required camera channel and time range, and enable audio if the recording contains it.
4. Convert the exported file to an MPEG transport stream with FFmpeg:

ffmpeg -i exported.mp4 -c:v libx264 -preset medium -crf 18 -c:a ac3 -b:a 192k -f mpegts output.mts

The -crf 18 setting produces high-quality H.264 while re-encoding; raise the value for a smaller file or lower it for less compression. If the source is already suitable and FFmpeg can copy its streams, try:

ffmpeg -i exported.mp4 -c copy -f mpegts output.mts

Stream copying is faster and avoids another generation of quality loss, but some MTS players require AVCHD-compatible H.264 and AC-3 parameters, so re-encoding is more compatible.

Try direct conversion with FFmpeg

First test whether FFmpeg recognizes the DAV container and codecs:

ffprobe input.dav

If it reports readable video and audio streams, convert directly:

ffmpeg -i input.dav -c:v libx264 -preset medium -crf 18 -c:a ac3 -b:a 192k -f mpegts output.mts

If FFmpeg reports an unknown format, invalid data, missing timestamps, or an unsupported codec, use the recorder’s player to export an intermediate file instead. Renaming .dav to .mts only changes the filename and does not perform conversion.

For a no-installation option, you can use the free converter on 101convert.com. Upload only footage that does not contain sensitive surveillance information, because online processing requires transferring the file to the service.

Quality, compatibility, and limitations

DAV exports may contain proprietary timestamps, multiple camera channels, motion metadata, or watermark data that will not survive conversion to MTS. Preserve the original DAV file when evidentiary authenticity, timestamps, or forensic verification matters.

MTS output is normally a valid MPEG transport stream, but not every file is a complete AVCHD structure. A device expecting an AVCHD folder, playlist, or specific profile may reject a standalone .mts file even when media players can open it.

Check the result with ffprobe output.mts or a media player and verify the beginning, middle, end, audio, frame rate, and synchronization. If the source uses H.265, an unusual surveillance frame rate, variable frame rate, or damaged timestamps, re-encoding with explicit H.264 settings is usually more compatible than stream copying.