on 06-07-2021 05:38 PM
I've just started using a Hero 9 Black and Telemetry Extractor Premium to review the data. I had assumed that "cts" stood for "camera time code", but if so, it doesn't agree with the number of seconds from the GPS data. For instance in a partial data set I get the folllowing when extracting GPS data at the "auto" sampling rate. I'm expecting 18 Hz.
Looking at the first two rows, I see .405 to .350 seconds between data points. So that's 0.055 seconds which is equal to 1/18 of a seconds and thus 18Hz. The "cts" values for those two rows differ by 1419.090778 - 1363.716222 = 55.374556. So it looks like cts is time in thousandths of a second. Is that correct?
|cts||date||GPS (Lat.) [deg]||GPS (Long.) [deg]|
06-08-2021 12:03 AM - edited 06-08-2021 12:04 AM
Yes. It's time in milliseconds.
By default (with Base Time: Auto), the Extractor will use the MP4 data to assign the CTS to GPS samples. If you want them based in the GPS timestamps alone (like the Date field), change Base Time to GPS.
I hope this helps.