A VidSyncDocument (.vsd) stores the project setup and references to the video files on disk. The videos remain separate files.
First-session checklist
- Place the original videos in a stable project folder and keep an unchanged copy of each source file.
- Use filenames that identify the camera, location, date, or take. Give the clips equally clear names inside VidSync, such as “Left Camera” and “Right Camera.”
- Load every clip and confirm that each file has been assigned to the intended camera.
- Choose the master clip and keep that choice for the life of the project. Measurement timecodes are expressed relative to the master clip, so changing it after measurements have begun can make later interpretation difficult.
- Save the VidSyncDocument immediately, then save it regularly during setup and analysis.
- Play all clips together long enough to confirm that the storage system can supply them smoothly.
Moving or renaming video files
If a project cannot find a video because the file was moved or renamed, select the corresponding Clip under the Project tab and use “Relocate Selected Clip.” Match each saved Clip to the correct file. Check camera identity carefully when the files look similar, because assigning a left-camera file to the right-camera Clip will invalidate the project setup until it is corrected.
Descriptive names reduce this risk. A filename such as Site3_2026-07-12_Left.mp4 contains more useful information than a camera-generated sequence number. If a project is moved to new storage, keep the folder structure intact when practical and open the project once to confirm that every clip resolves correctly.
Video file compatibility
VidSync uses the macOS video framework for playback. A useful preliminary check is whether the file plays correctly in QuickTime Player on the same computer. Confirm that the image, duration, and frame stepping behave as expected before beginning a long analysis. Keep the source files unchanged after measurements begin; replacing a file with a re-encoded version may change timing or frame correspondence.
Storage and playback performance
The tutorial recommended placing high-resolution camera files on separate hard drives. That recommendation reflected the sustained read speed of the drives commonly used when the tutorial was recorded. A current internal SSD or a sufficiently fast external SSD may play several clips smoothly from one volume. Test the intended storage with all clips playing together at the resolution required for analysis. If playback stutters, copy the videos to faster local storage or divide the camera files among independent drives.
A network or cloud-synchronized folder may be convenient for transfer, but video playback should use files that are fully available on the local computer. Files that are still downloading or are represented only by online placeholders can interrupt playback.
Using multiple computers
You can keep VidSyncDocument files in a folder synchronized by a service such as Dropbox. Allow synchronization to finish before opening the project on another computer, and avoid editing the same project on two computers at once. Keep an independent backup of the .vsd file and the videos.
If the video files have identical paths on both computers, the clips will not need to be relocated each time you switch. One approach is to use the same external drive on both systems. Another is to store the videos in disk images with the same volume and folder names on each computer. For example, both systems could present a file at /Volumes/MyVideoDiskImage/MyVideo-Left.mp4. If matching paths are inconvenient, use “Relocate Selected Clip” on each computer and verify every camera assignment before continuing.