I have not tried pulling the card out of the camera and transferring directly from the card to the laptop.
Instead, I tap View Time Lapse in the Wyze app, which takes me to the album. Then tap the time-lapse thumbnail to download it, which copies it from the camera to the phone. There may be some conversion going on when this happens.
From there, open the time-lapse and tap the share button. From there, you can email it, message it, save to dropbox, save video, etc to get it to your laptop.
When it gets to the laptop, it’s an .mp4 file, which plays fine in QuickTime Player (10.4), QuickTime Player 7 (7.6.6) and VLC (2.2.8).
The .mp4 video comes in at 30fps. Knowing that, you can calculate finished duration based on the time-lapse interval and length. For example, I just recorded a short 4.5 minute time lapse with an interval of 3 seconds.
4.5 minutes * 60 sec/minute = 270 seconds total length
270 seconds divided by 3 second interval = 90 total frames
90 frames divided by 30 fps = 3 seconds = duration of finished video