Free online TREC to MTS converter

What the TREC format is

TREC is Camtasia’s proprietary recording format, used by Camtasia 9 and later for screen captures with video, microphone audio, system audio, cursor data, and editing metadata. You encounter it in Camtasia’s recording folders or when another user sends you an unfinished Camtasia screen recording. TREC is intended for editing inside Camtasia, not for general-purpose playback or device compatibility.

What the MTS format is

MTS is an MPEG transport-stream container commonly associated with AVCHD camcorders, Blu-ray-compatible workflows, and video editors that expect transport-stream input. It can contain H.264 video and compressed audio such as AC-3. MTS is useful when a playback device, editing application, or archival workflow specifically requires an AVCHD-style transport stream; it does not preserve Camtasia’s cursor, callout, timeline, or project-editing data.

How to convert TREC to MTS

Using Camtasia and FFmpeg

1. Open the .trec recording in Camtasia. If Camtasia cannot open it, use the Camtasia version that created the recording or ask the sender to export it.
2. Export an intermediate video through Export → Local File. Select MP4, keep the original recording dimensions and frame rate, and enable audio. Save the result as recording.mp4.
3. Install FFmpeg and run this command to create an MTS file with H.264 video and AC-3 audio:

ffmpeg -i recording.mp4 -c:v libx264 -preset medium -crf 18 -pix_fmt yuv420p -c:a ac3 -b:a 256k -f mpegts recording.mts

The -crf 18 setting produces high visual quality but re-encodes the video. Use a higher CRF value such as 20 or 23 for a smaller file. If the intermediate MP4 already uses compatible H.264 video and audio, you can try remuxing without video re-encoding:

ffmpeg -i recording.mp4 -c:v copy -c:a ac3 -b:a 256k -f mpegts recording.mts

Remuxing is faster and avoids another generation loss, but some AVCHD devices reject streams with unsupported resolution, frame rate, profile, bitrate, or audio parameters. Re-encode when hardware compatibility matters.

Using the online converter

You can convert the file for free on 101convert.com without installing software: upload the TREC file, select MTS as the output format, start the conversion, and download the result. Uploading transfers the recording to a remote service, so use Camtasia and FFmpeg instead for confidential screen captures.

Quality and compatibility limitations

The TREC-to-MP4 export determines the available image quality; converting that MP4 to MTS cannot restore detail already lost during export. Check the output with the intended device or editor because the .mts extension alone does not guarantee AVCHD compliance. For broad compatibility, use H.264 video, yuv420p pixel format, a supported frame rate, and AC-3 audio; exact AVCHD limits vary by hardware. Keep the original TREC and Camtasia project if later edits, cursor changes, or annotations may be required.