I keep second-guessing myself on the math, so I wanted to put what I have out here and see if anyone can poke holes in it for me.

**Conversion: Time --> Percent or Timecode = you must multiply the percent or timecode value by the absolute value of the speed**

T-->P/TC Examples: (Assuming a 10 second video that's 30 fps)

- Speed 1, Input: 1 sec --> Output: 10% / 00:00:01:00/30
- T--> P: 1 sec = 10% of 10 seconds --> 10% x |1| = 10%
- T--> TC: 1 sec = 00:00:01:00/30 --> 00:00:01:00/30 x |1| = 00:00:01:00/30

- Speed -1, Input: 1 sec --> Output: 10% / 00:00:01:00/30
- T--> P: 1 sec = 10% of 10 seconds --> 10% x |-1| = 10%
- T--> TC: 1 sec = 00:00:01:00/30 --> 00:00:01:00/30 x |-1| = 00:00:01:00/30

- Speed 2, Input: 0.5 sec --> Output: 10% / 00:00:01:00/30
- T--> P: 0.5 sec = 5% of 10 seconds --> 5% x |2| = 10%
- T--> TC: 0.5 sec = 00:00:00:15/30 --> 00:00:00:15/30 x |2| = 00:00:01:00/30

- Speed 2, Input: 1 sec --> Output: 20% / 00:00:02:00/30
- T--> P: 1 sec = 10% of 10 seconds --> 10% x |2| = 20%
- T--> TC: 1 sec = 00:00:01:00/30 --> 00:00:01:00/30 x |2| = 00:00:02:00/30

- Speed -2, Input: 1 sec --> Output: 20% / 00:00:02:00/30
- T--> P: 1 sec = 10% of 10 seconds --> 10% x |-2| = 20%
- T--> TC: 1 sec = 00:00:01:00/30 --> 00:00:01:00/30 x |-2| = 00:00:02:00/30

- Speed 0.5, Input: 1 sec --> Output: 5% / 00:00:00:15/30
- T--> P: 1 sec = 10% of 10 seconds --> 10% x |0.5| = 5%
- T--> TC: 1 sec = 00:00:01:00/30 --> 00:00:01:00/30 x |0.5| = 00:00:00:15/30

- Speed -0.5, Input: 1 sec --> Output: 5% / 00:00:00:15/30
- T--> P: 1 sec = 10% of 10 seconds --> 10% x |-0.5| = 5%
- T--> TC: 1 sec = 00:00:01:00/30 --> 00:00:01:00/30 x |-0.5| = 00:00:00:15/30

- Speed 1, Input: 0.5 sec --> Output: 5% / 00:00:00:15/30
- T--> P: 0.5 sec = 5% of 10 seconds --> 5% x |1| = 5%
- T--> TC: 0.5 sec = 00:00:00:15/30 --> 00:00:00:15/30 x |1| = 00:00:00:15/30

- Speed 0.5, Input: 0.5 sec --> Output: 2.5% / 00:00:00:08/30
- T--> P: 0.5 sec = 5% of 10 seconds --> 5% x |0.5| = 2.5%
- T--> TC: 0.5 sec = 00:00:00:15/30 --> 00:00:00:15/30 x |0.5| = 00:00:00:08/30

**Conversion: **

P-->T/TC Examples: (Assuming a 10 second video that's 30 fps)

- Speed 1, Input: 10% --> Output: 1 sec/ 00:00:01:00/30
- P-->T: 10% of 10 seconds = 1 sec --> 1 sec x |1| = 1 sec
- P-->TC: 00:00:10:00/30 x 0.1 = 00:00:01:00/30

- Speed -1, Input: 10% --> Output: 1 sec/ 00:00:01:00/30
- P-->T: 10% of 10 seconds = 1 sec --> 1 sec x |-1| = 1 sec
- P-->TC: 00:00:10:00/30 x 0.1 = 00:00:01:00/30

- Speed 2, Input: 5% --> Output: 0.25 seconds / 00:00:00:15/30
- P-->T: 5% of 10 seconds = 0.5 sec --> (0.5 sec)/(|2|) = 0.25 secs
- P-->TC: 00:00:10:00/30 x 0.05 = 00:00:00:15/30

- Speed 2, Input: 20% --> Output: 1 sec / 00:00:02:00/30
- P-->T: 20% of 10 seconds = 2 seconds --> (2 seconds)/(|2|) = 1 sec
- P-->TC: 00:00:10:00/30 x 0.2 = 00:00:02:00/30

- Speed -2, Input: 20% --> Output: 1 sec / 00:00:02:00/30
- P-->T: 20% of 10 seconds = 2 seconds --> (2 seconds)/(|-2|) = 1 sec
- P-->TC: 00:00:10:00/30 x 0.2 = 00:00:02:00/30

- Speed 0.5, Input: 5% --> Output: 1 sec / 00:00:00:15/30
- P-->T: 5% of 10 seconds = 0.5 sec --> (0.5 sec)/(|0.5|) = 1 sec
- P-->TC: 00:00:10:00/30 x 0.05 = 00:00:00:15/30

- Speed -0.5, Input: 5% --> Output: 1 secs / 00:00:00:15/30
- P-->T: 5% of 10 seconds = 0.5 sec --> (0.5 sec)/(|-0.5|) = 1 sec
- P-->TC: 00:00:10:00/30 x 0.05 = 00:00:00:15/30

- Speed 1, Input: 5% --> Output: 0.5 secs / 00:00:00:15/30
- P-->T: 5% of 10 seconds = 0.5 sec --> (0.5 sec)/(|1|) = 0.5 sec
- P-->TC: 00:00:10:00/30 x 0.05 = 00:00:00:15/30

- Speed 0.5, Input: 2.5% --> Output: 0.5 sec / 00:00:00:15/30
- P-->T: 2.5% of 10 seconds = 0.25 sec --> (0.25 sec)/(|0.5|) = 0.5 sec
- P-->TC: 00:00:10:00/30 x 0.025 = 00:00:00:8/30

If I'm not mistaken, then the math and examples for converting Timecode to Time should be the same, but to convert Timecode to Percentage you'd just divide to total timecode duration by the given timecode value in order to get the percentage value (no speed involved).

Did I do the math correctly?

]]>It gives me a headache

Me too. After I finish the User Actor, I never want to have to do this math again.

]]>I think I've got it figured out at this point though (unless someone tells me I'm wrong).

It gives me a headache...

Cheers,

Hugh

]]>I think some of what you are looking for is covered there.

Some, yes, but the tricky thing is accounting for speed. I think I've got it figured out at this point though (unless someone tells me I'm wrong).

]]>Take a look at these User Actors: https://troikatronix.com/add-o...

I think some of what you are looking for is covered there.