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-   -   1080p (https://www.dvinfo.net/forum/general-hd-720-1080-acquisition/28760-1080p.html)

Anja Schuetz July 11th, 2004 01:12 PM

1080p
 
Hallo!
Imagine one day it will be possible to broadcast 1080p, if so would it be easer to change from 1080i to 1080p or from 720p to 1080p?
In short :Is it easier to switch to 1080p from HDV1 or HDV2?
Thanks already! Bye

Heath McKnight July 11th, 2004 07:58 PM

I believe interlaced is easier than progressive.

1080p is for HD DVDs. 720p is perfect for going to HD DVDs!

heath

Frederic Lumiere July 12th, 2004 07:20 AM

Anja,

It is easier to go from 720p to 1080p than 1080i to 1080p.

The reason is that 720 > 1080 is a simple resolution upconversion but interlaced to progressive is more problematic because interlaced offers only half the data at any point in time (1 field at a time).

HDV doesn't include 1080p in its specs, just 720p and 1080i.

Anja Schuetz July 12th, 2004 08:46 AM

Thank you very much.
I know it is not in the specs, but I am trying to figure out why one or the other standard is chosen, because one day 1080p may be of concern and than it is easier to integrate 720p.
Thanks!

Maury McEvoy July 12th, 2004 08:57 AM

HDV(720p) > DiVA > 1080p
 
Hi Anja,

I use DiVA to convert the video portion of all of my MPEG-2 HDV data to QuickTime movies. I then drop those QT movies into my FCPHD browser.

DiVA provides a scaling option that can be used to upconvert to 1080p.

DiVA also has a cropping option that can be used to clean up the edges of HDV images.

Try it! DiVA is free and it works very well.

The only downsides are the resulting large data files and high data rates.

Note: You will not 'need' the 3ivx codec.

Maury

Anja Schuetz July 12th, 2004 09:24 AM

Great! Thanks for the info!

Graham Hickling July 12th, 2004 11:10 AM

Doesn't the best solution depend on whether we are talking 1080p30 or 1080p60?

I'd agree that the best route to 1080p30 would be simple upscaling from 720p60.

But wouldn't the best results, at least in terms of motion, for 1080p60 be by linedoubling and upscaling of 1080i?

Graham Hickling July 12th, 2004 11:11 AM

Oops....typo in that previous post! I meant:

" ..best route to 1080p30 would be simple upscaling from 720p30"

Frederic Lumiere July 12th, 2004 11:19 AM

Graham,

The problem with interlaced is that with high motion, field 1 and 2 don't necessarily match.

It is always better to go from progressive (720p) to progressive (1080p) than interlaced (1080i) to progressive (1080p).

In the first case, you upconvert where in the second you often are missing data. Field 1 is only half the image and with too much motion, field 2 isn't the completion to field 1 anymore. A whole object could be missing in field 2 that exists in field 1.

Graham Hickling July 12th, 2004 02:31 PM

Hi Frederic,

I was basing my suggestion on the assumption that Anja wants to end up with 1080p60 footage in the future, and that he is trying to decide between shooting in 720p30 (30 frames/sec) or 1080i (60 fields/sec) until technology and cost make that feasible.

If all he wants is 1080p30 then I completely agree that upscaling his 720p30 will be fine.

But wouldn't the best way to get to 1080p60 be to line-double each 1080i field into a full frame? He would only achieve 540 lines of horizontal resolution, but it would provide him with a genuine frame rate of 60 unique frames per second (which isnt available from 720p30).

Anja Schuetz July 12th, 2004 11:48 PM

So- if I am right,let me get this straight, then I need to double my lines from 1080i to get 1080p for each field, if I don`t want to deinterlace-logical.
And I would have to upconvert resolution of 720 to 1080, and to get 60p I would have to also double the frames to get 1080 60p!?
Either way, sounds like motion will look strange.
I could not find any objective tests concerning that theme, but they would sure be interesting!

Graham Hickling July 13th, 2004 12:47 AM

I doubt there'd be any value in doubling the frames of 720p30 to get p60 - you'd end up with footage that was just successive pairs of identical frames.

(In contrast, with interlaced footage each field is unique, though only half the vertical resolution of a full frame)

Frederic Lumiere July 13th, 2004 10:28 AM

I lost track of what we're trying to do.

Anja Schuetz July 13th, 2004 10:52 AM

Actually I was just trying to figure out why Sony chose the 1080i and JVC the 720p standard. I thought it may have something to do with the ability to integrate it-one day- in a 1080p environment, but left out the question of 30p or 60p.

Frederic Lumiere July 13th, 2004 10:56 AM

Anja,

There are two standards for HDV:

720p (1280 X 720 30fps progressive)
1080i (1440 X 1080 60fps Interlaced)

These two standards also match HD broadcaster's requirements. Fox HD is 720p, CBS is 1080i.

There is no 1080p planned out for HDTV.

1080p however is often used for film conversion (24p).


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