So far I have learned that times and dates recorded by the camera do need some filtering…
These are the variables I can “play” with:
- file date (usable for the moment of the last frame)
- number of frames & frame rate => total time recorded
- via “ffmpeg” the moment of the first frame
I have done some testing by taking images and interval movies of a synced clock. Images are just fine, there does appear to be some delay, but it’s something like half a second at most. For MP4 however: to my surprise there appears to be some sort of error in the time found by ‘ffmpeg’ for the start time, it is exactly a whopping 10 seconds earlier than the time I see on the clock!
Then the rest just became much easier… with more then 75 images the file time is about a second later, another for about 150 images and one more with more then 300 images.
And more importantly: try to reduce the variables:
It may sound so obvious, but when using external GPS recording for later matching it’ll make you’re life so much easier when you know how to synchronize the time of your camera with the GPS time.
The internal clock of your camera most likely isn’t perfect… I just found out that after the last time I synced the time with my phone about three months have passed and the time of the camera was a whopping 6 seconds out of sync!
So remember: before you go: sync the time of your camera with GPS!
The time recorded of your GPS device most likely is in (exact) sync with the time broadcasted by the GPS satellites (it doesn’t get much better than that!)
For the YI360:
- connect your app to the camera
- tap the gear symbol (top right)
- scroll to the bottom and tap ‘others’
- tap: ‘correct camera time’
PS: I honestly don’t understand why this isn’t done by default upon connecting the camera to app