# [mythtv-users] 5200 or 6200

Nick Morrott knowledgejunkie at gmail.com
Thu Jan 25 05:29:54 UTC 2007

```On 25/01/07, Jarod Wilson <lists at wilsonet.com> wrote:
> On Jan 24, 2007, at 16:44, Nick Morrott wrote:
>
> >> On 1/24/07, Rich West <Rich.West at wesmo.com> wrote:
> >>>> Okay, read it, and I read it to say that 1080p60 is indeed 2x the
> >>>> resolution of 1080i60, but that 1080p24 and 1080p30 are more
> >>>> commonly
> >>>> found in the wild today.
> >>>>
> >>
> >> fields vs frames my friend. two fields = 1 frame.
> >> (1080 / 2) * 2 = 1080.
> >
> > I'm not sure what the fields vs frames 'proof' adds to the argument
> > without taking into account the relative refresh rates of fields vs
> > frames also. Fields are irrelevant with progressive video as whole
> > frames are displayed.
> >
> > 1080p60 has twice as many pixels/s as 1080i60, as Jarod stated
> > earlier:
> >
> > 1080i60 = (1920x540 pixels per field) x (60 interlaced fields per
> > second) = 62,208,000 pixels/second.
> >
> > 1080p60 = (1920x1080 pixels per frame) x (60 progressive frames per
> > second) = 124,416,000 pixels/second.
>
> Yep, that's more or less the same math I came up with... Also, note
> the mention on the page I linked to stating how 1080p60 raises
> bandwidth requirements versus 1080i60 "from 1.493 Gb/s to nominally 3
> Gb/s."

That agrees with my maths (and the necessity of dual-link):

1080i60 = 62,208,000 pixels/second x 24bits/pixel = 1,492,992,000
bits/second = ~1.5Gbps

1080p60 = 124,416,000 pixels/second x 24bits/pixel = 2,985,984,000
bits/second = ~3.0Gbps

Either way you look at it, that's a lot of data :)

Nick
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