[ardour-dev] Timecode computation error

[Chris Goddard]

On Thursday 16 November 2006 14:33, you wrote:
> On Thu, Nov 16, 2006 at 01:40:13PM +0000, Chris Goddard wrote:
> > When selecting 25fps I would expect the timecode to count 25 frames per
> > second, i.e. 0 -> 24.
> >
> > If I select 24.976 I would expect the frame count to be 25 frames per
> > second again (0 -> 24) but just running slightly slower.
>
> Running 1/1000 slower and skipping the first two frames of every minute
> except when minutes is a multiple of 10, to keep average speed of time
> correct.
>
> The non-integer rates are always 'drop frame' variants of the nearest
> integer rate, they don't make sense otherwise. 

That's not really true. From a purely maths point of view you may be right, 
but that's not always the case from a work flow point of view. Take 23.976 
for example. This is run non-drop when when filming in 24p.

> They should indeed count 
> up to corresponding integer rate minus one, 

As I reported some rates don't seem to. 23.976 for example counts 00 -> 22 
every second.

> but occasionally wrap to 
> 2 instead of 0.

Only if you really should be set to drop frame.

> So for 30 fps DF, the frame following 00:00:59:29 is 00:01:00:02.
> The real frame rate is then 29.97 fps.

agreed

-- 
Cheers

Chris