[MPlayer-dev-eng] [PATCH] -identify DVD titles

[kiriuja]

On 9/19/05, Rich Felker wrote:
> On Mon, Sep 19, 2005 at 10:29:00PM +0200, Guillaume POIRIER wrote:
> > I'm also not too sure that 
> > +  static int framerates[4] = {0, 2500, 0, 2997};
> > +  int framerate = framerates[(dt->frame_u & 0xc0) >> 6];
> > +  int msec = (((dt->hour & 0xf0) >> 3) * 5 + (dt->hour & 0x0f)) * 3600000;
> > 
> > is well supported by ol' compilers such as GCC-2.95. Could you check that?
> 
> The code is perfectly fine syntactically, even in traditional C, but
> plain wrong in what it does. The numbers are 25 and 30000/1001, not 25
> and 29.97!!

So, 30000/1001 = 29.97002997, which is more than enough precision for this case,
since it is only dt->frame_u, which is the sub-second part, that gets converted
using this rate, and so even though the code prints 3 digits, the actual
precision is less that 2 digits here.

Should there be parentheses around the numerator here? so that the whole thing
is divided by the framerate? like:

msec += (((dt->frame_u & 0x30) >> 3) * 500 + (dt->frame_u & 0x0f) * 100000) / framerate;

If there is anything else I am missing, please explain.

--
kiriuja