[MPlayer-dev-eng] container format

[Fabian Franz]

Am Donnerstag, 6. Februar 2003 18:37 schrieb Arpi:
> Hi,
>
> another issue:
>
> time_base
>         the number of timer ticks per second, this MUST be equal to the fps
>         if the fixed_fps is 1
>         MUST be < 2^15
>
> fixed_fps
>         1 indicates that the fps is fixed
>
> fixed fps is usually fractional like 23.976 ro 29.97 or so...
> so the fixed_fps can't be used here.
>
> imho we should 'steal' teh method from avi files: use multiplier and scale
> pair, ie store 2 numbers a and b, and get the fps=a/b

What about Andriy Gritsenko's way ?

">And one question...how do we plan on handling non-integral framerates?
>(29.97 and 23.976 come to mind... :) Is the time base a fixed point
>number, and if so, do we need to specify the precision on a per-file
>basis?

I think it may be done with one additional bit - integer framerate and
optional divider (if flag is 0 then 1.0 and otherwise 1.001 - see MPEG
standard) so you can have these 29.97 as 30/1.001 and the same 23.976
as 24/1.001. :)

    With best wishes.
    Andriy."

cu

Fabian

>
>
> A'rpi / Astral & ESP-team