Uploads & video files FAQ

Accepting the file type is not the same as being able to play it. The final check is whether your browser can decode the video — an iPhone clip saved in the high-efficiency format opens in Safari on iPhone and Mac, but not in every desktop browser. See when an iPhone video will not load.

Photos, audio files, GIFs and links to videos online cannot be analysed; Motion Lab needs the video file itself.

Choosing a file in Motion Lab opens it inside your browser — the video is not sent to a SwingVantage server. More in is my swing video private?

A file over 500 MB is turned away before it is opened, with a message giving its size. Between 200 MB and 500 MB it is accepted, but a very large file takes longer for your browser to read and is more likely to time out on a slower phone.

To make a file smaller, trim it to the rep before you upload, or export it at a lower resolution — 720p keeps it small without dropping below what the quality check asks for.

The length check happens once your browser has opened the file, so a long video can take a few seconds before it is refused.

Some recorded clips do not state their length inside the file. Motion Lab works it out by jumping to the end; if it still cannot tell, it carries on rather than rejecting the clip.

Have a long recording? Trim it to the rep on your phone first, or see uploading a whole practice session.

What probably happened: iPhones often save video in the high-efficiency format inside a .mov file. Safari on iPhone and Mac opens these; some desktop browsers cannot, and they neither play the file nor report an error — so Motion Lab waits, then tells you.

1. Upload from the iPhone itself, in Safari, where the format opens.
2. Or re-save or export the video as an MP4 (H.264) and upload that copy.
3. If you see "That file is empty (0 bytes)", pick the video again — the copy may not have finished.
4. If you see "The file may be corrupted", export or copy a fresh version of the video.

Only re-film if a fresh export still will not open. If it keeps failing in one browser, try another before anything else, and tell us if none of them work.

Stay on the progress screen until the results appear. How long it takes depends on your device and the clip; shorter clips and newer devices finish sooner.

As soon as analysis starts, the clip is saved on your device. If the run is interrupted — a reload, a crash, a closed tab — the next time you open Motion Lab it shows "We kept your last clip" with Continue and Discard, for up to 48 hours.

Cancel analysis stops the work but keeps your clip, so you can change a setting and run it again without choosing the file again. If it stops with an error instead, see when an analysis does not finish.

On a computer, drag the file onto the upload area or click to browse.

Once the clip opens you get a trimmer to cut it down to the rep, plus handedness and skill level to set. Camera angle and tracking accuracy sit under Advanced capture settings, and are optional.

If a message says the file is empty, pick it again — the copy from your library may not have finished.

It usually means the clip was filmed at a low setting, cropped heavily, or passed through an app that shrinks video when it shares it.

Next time, record at 720p or higher. If you are re-using an older clip, the original file on the phone that filmed it is usually sharper than a copy that has been shared around.

• "That file is empty (0 bytes)" — pick the video again; the copy may not have finished.
• "Unsupported file type" or "Unrecognized video format" — use one of the accepted formats (MP4, MOV and WebM).
• "File is too large" — trim it or export it smaller; the limit is 500 MB.
• "Video is too long" — trim it under 5 minutes; 5 to 10 seconds around the rep is ideal.
• "Couldn't read this video in your browser" — export it as an MP4 (H.264); see iPhone videos.
• "The file may be corrupted" — export or copy a fresh version of the video.

A clip that opens but in which no person can be found is not rejected: it is analysed, and the results say it could not support a read. See when Motion Lab cannot find you.

What works: several reps close together. Motion Lab finds each swing, analyses it on its own, and summarises the set — best swing, most repeated miss and the average. The summary covers the first 8 swings, and a swing with too few tracked frames is listed without a score rather than guessed.

What does not: a long recording with minutes of setup, ball-collecting and chat between swings. Cut it into short clips — on your phone before uploading, or with the trimmer in Motion Lab — and analyse them one at a time.

Analysing an entire practice session from one long recording is not something Motion Lab does today.

These clips never leave the device. When you are signed in, your analyses sync to your account without the video — just the reads, a compact motion track and, for some swings, one still frame for the swing trace — so on another phone or computer you will see your results but not the clip.

A clip from an interrupted analysis is kept there too, for up to 48 hours, until the analysis succeeds or you discard it. Removing a session also removes its clip, and clearing your browser's site data removes all of them.

Some browsers keep fewer clips, and a private window may keep none once it is closed. If a clip is gone, re-analysing just means choosing the file again. More in where your data is stored.