480i or 1080i setting for non-HD programming

If you have the HR20 in Native mode, it passes SD channels as 480i, you don't need to change the resolution manually. Regardless, it comes down to what scales better, your HR20 or your set, try both settings and use what looks best to you.

Are there any 16:9 480i channels around in the US on this platform. In the UK Sky HD carries both 576i and 1080i services, with the 576i stuff a mix of 4:3 and 16:9. The aspect ratio switching is MUCH better if you chose Automatic (sadly it won't do Native as the 576i is de-interlaced to 576p via HDMI - unless you do a complex EDID spoof), as the display correctly switches between 4:3 (in your chosen viewing mode) and 16:9 on SD stuff - which it doesn't do as well with a permanent 1080i or 720p output.

This may be irrelevant to the US experience - but I've found aspect ratio switching to be quite a key factor in the set-up of my system.

What I have found works best for me and those I have set up for folks is to have it set to "Native", then enable 480p,720p and 1080i but not 480i, This allows the first thing in to be 480p and whatever comes in is passed through in it's native resolution. Look at the blue lights on the lower right hand side of the receiver and when you have a SD program coming in the blue light will be on 480p. When you have ESPN coming in which is 720p you will see the blue light go to 720p and if the broadcast is in 1080i you will see the blue light go to 1080i. Again this simply allows incoming signals to be passed through in their native resolution.

The Public Broadcasting Service (PBS) puts out a fair number of shows at 480i 16X9, described in program openings or schedules as 'letterboxed'. With a 1080i CRT RPTV that displays only 1080i or 480p (with 480i input), I've set my cable HD STB to output only 1080i. 1080i's finer resolution helps mask any 480i deficiencies. With STB 1080i output, SD shows appear with gray sidebars, minimizing worries about CRT 'burn-in---still unobserved after 7+ years with the same display. Several years back I only watched 480i (from S-video) as 480p, with Panoramic mode stretching to 16X9, then switched the RPTV mode to HD for 1080i viewing. Improved STB upconversion to 1080i made it possible to view everything at 1080i; early HD STBs made upconverted 1080i images too contrasted and fuzzy. -- John

So, if I leave it at native, and it is connected via HDMI to my Onkyo 605 which upconverts, and my TV is 720P, will the signal upconvert to 720P through the receiver to the TV? And if so, will a 1080i signal get downconverted by the receiver to 720p, or does it pass through at 1080i but only can be viewed as 720p? Am I confused?

Yep - my question is whether any US broadcasters broadcast 480i 16:9 full-height (sometimes called anamorphic) - similar to 16:9 DVDs "enhanced for widescreen TVs" - which are not letterboxed unless they are a wider aspect ratio than 16:9. (Most mainstream UK broadcasters use 16:9 576/50i as their main broadcast and production format - with no letterboxing )

It is still 480 and in my opinion you get a little picture improvement. With the HR20 480p downloads just fine.

A lot of consumer electronics devices that have HDMI and handle 480i video end up having to run it through a deinterlacer or line doubler anyway, since 480i's bitrate over HDMI is actually too low for the HDMI spec.

Hasn't that been solved by the "pixel doubling" solution - where each pixel/sample is sent twice to get the "pixel clock" rate up to a high enough level?

Instead of a 720 active sample/pixel line a 1440 active sample/pixel line containing each pixel repeated (and not filtered) is sent - with the display knowing this and discarding one of the two pairs of repeated samples/pixels.

This avoids any requirement for line-doubling or de-interlacing to progressive?

AIUI this was added to the spec - so some displays may not support it - which is why some sources err cautiously and de-interlace to 480/576p when showing a 480/576i source...

Can anyone help on this one?

If your TV has a 720p native resolution, that is all it can display. If you send it some other signal, the TV has to convert it to 720p. If you convert the signal to 720p before it gets to the TV, then it displays that signal untouched. As to which component - STB or your TV - handles the conversion best, only you can tell.

Dana

I've set my SA8300HD cable box to output only 1080i from its YPbPr output. 480i from my digital-only cable service (QAM) definitely looks better upconverted to 1080i. Also have a rarely used S-video cable hookup that permits viewing 480i at 480/60p, with a Genesis deinterlacer chip in my 64" 1080i CRT RPTV. -- John

I have my HR20 set to "pure" native (i.e. native "on", and 480i, 480p, 720p, and 1080i all checked), since I have to believe that my $4K TV does a better job scaling and deinterlacing than my $100K DVR.

--Mav

I have native on as well and everything checked. My TV supports 480i through 1080p, but displays 720p at the highest. The 480i stuff looks like jusnk, is there any way to fix that or do I suffer?

The 720 and 1080 sources look great.

There is no way to improve 480i. It always looks terrible on HD sets due to being able to see all of the flaws. For me, having lots of HD channels is just a way for me to avoid 480i programmin.

Yeah, that is the way I look at it. So, the box nor the TV can upscale and make it look better even though my TV is 720p?

I run my 42 inch LCD 1080P through my Comcast DCT 6416 HDDVR cable box. I have it set to 1080I and 16:9, since 1080I is the highest for now you can run a cable box. In 4:3 override I have it set to 480I. I tried 480P, 720P and 1080I, and the 480I setting gave me the best picture you can for SD. Of course watching HD channels and PS3 are clearer pictures, but all you have to do to watch on the cable box is change the settings on the box.

For Comcast models DCT6412 and DCT6416, to change the settings turn Cable and the TV on. Hit cable button, power off, then hit the Menu button. You will see a menu pop up where you can change the settings. Set it to 1080I, 16:9 and if 4:3 override set it to 480I. You will see a big difference. Most cable boxes allow you to change settings.

Whoops, strike that, remove the "K", $100.00 DVR...

--Mav

Let's put it this way. 720p, 1080i, and 1080p have more data to begin with, so how well the TV scales/deinterlaces vis a vis the HR20 in not particularly relevant on those sources. They look great [almost] no matter what -- hence, "HD". 480i sources, on the other hand, need a lot of help to look good or even passable on a 1080p or 720p set (and this problem is magnified the bigger the set gets). 480i is where the scaler/deinterlacer used to process the 480i source really makes its money. If you pass 480i natively, then you're letting the TV handle the scaling/deinterlacing chores. Look at that and see what you think. Then, turn native off and disable 480i and 480p on the HR20 (if you do that, you're letting the HR20 handle those tasks). Look at that and see what you think. Then decide which one you like better (or, rather, which one you hate the least).

So, in the end, you can't really hope for 480i content to look as god as 720p/1080i/1080p content, all you can hope for is that it looks less bad with either the TV or the HR20 doing the processing.

Hope that makes sense.

I had a question recently in another thread that never got answered. I think it applies here, so I'll ask again.

I have a Samsung 5884 Plasma (1080p). In general, is a better picture typically produced by outputting to 1080i or 720p on the STB for a 1080p display?

In other words, being that I will be viewing both 1080i and 720p HD channels, one of them will be converted by the STB before going to the display (depending on the STB output I choose). Conversely, is there no hard-fast rule, and only the eye of the beholder to judge?

Thanks.

All other things being equal, and assuming the STB won't allow you to output "native" (which would probably be preferred given that your TV can probably process the material better than your STB), and assuming you don't want to go change the output format when you change between networks broadcasting in different resolutions (i.e. ABC in 720p and CBS in 1080i, etc.), 1080i should be better because there are fewer steps in the process. Here's the not so quick and dirty reason why.

Depending on what channel you're watching, one of 3 different resolutions will be coming into your STB -- 480i, 720p, or 1080i. Since your 1080p TV will only display at 1080p, all three of these will need to be "converted" in some way by some thing to 1080p before the image is displayed on the screen.

Remember, generally speaking, (i) the fewer the processes the better, (ii) you want your more "competent" component (probably your TV as opposed to your STB) to handle as many of the processes as it can, and (iii) you usually don't want it processed twice (i.e. once by the STB and again by the TV). With that in mind, here we go (processes are in brackets following the component performing the process):

If you set your output resolution to 720p:

Incoming 480i material-->STB--[scaled up to 720]--[deinterlaced to p]-->TV--[scaled up to 1080]-->Picture [STB: 2 steps; TV: 1 step]

Incoming 720p material-->STB-->TV--[scaled up to 1080]-->Picture [STB: 0 steps; TV: 1 step]

Incoming 1080i material-->STB--[scaled down to 720]--[deinterlaced to p]-->TV--[scaled back up to 1080]-->Picture [STB: 2 steps; TV: 1 step]

If you set your output resolution to 1080i:

Incoming 480i material-->STB--[scaled up to 1080]-->TV--[deinterlaced to p]-->Picture [STB: 1 step; TV: 1 step]

Incoming 720p material-->STB--[scaled up to 1080]--[interlaced to i]-->TV--[deinterlaced to p]-->Picture [STB: 2 steps; TV: 1 step]

Incoming 1080i material-->STB-->TV--[deinterlaced to p]-->Picture [STB: 0 steps; TV: 1 step]

So, in the end, here's what you have:

For 480i material, there's one fewer step if output resolution is set to 1080i.

For 720p material, there's two more steps is output resolution is set to 1080i.

For 1080i material, there's two fewer steps if output resolution is set to 1080i.

So, 1080i is the "better" output setting for 480i SD, a "worse" output setting for 720p HD, and a "better" output setting for 1080i HD. Although there are notable exceptions (ABC, Fox, ESPNs, etc.), *most* HD channels broadcast in 1080i. Since setting your output resolution to 1080i will handle 480i SD content and 1080i HD content "better", I've concluded that 1080i is the better output resolution to set it at if you must chose one (again, all other things being equal, if you can output "native", that's generally going to be better).

All that said, what matters is what looks best to you.


--Mav

Maverickster2,

Thank you for the explanation - very thorough. I will add that my STB allows SD output settings separately (4:3 override). My options are 480i, 480p, off, and stretch. 'Off' basically converts in the STB to whatever I've chosen for HD (1080i or 720p). 480i keeps it in it's native format (i.e. STB doesn't convert). I'm assuming that the ideal method would be to set it to 480i, and allow my display to do all of the conversion? [TV: 2 steps]

Again, thanks alot!