# Deinterlace problem with 1080i and non-HD channels on Samsung



## podder320 (Mar 4, 2007)

I have a Samsung 1080p DLP TV (model HL-S6187W) and the 622 receiver. Using either HDMI or component, I see something bad on non-HD channels.

The problem is this: non-HD satellite channels are deinterlaced wrong. The even/odd lines are inverted, displayed as odd/even. It happens everywhere, on every non-HD channel, and it is obvious with non-moving high-contrast curved shapes, like the Comedy Central logo in the corner of the screen. 

When displaying HD channels with the 622 putting out 1080i, everything is fine. When I set the receiver to 720p mode, or 480p or 480i and show a non-HD channel, there is no problem. The problem only happens on non-HD channels when the receiver is set to 1080i - and it happens on all of them, all the time. I'm not zooming or stretching anything with the 622 or the TV.

I don't want to consign myself to 720p when some channels are in 1080. Toggling the receiver between 720p and 1080i is too much trouble and not spouse-acceptable.

It's very hard to describe this to support in a way that's helpful. If somebody can tell me how to reach the right people at E* that would be great.

Does anybody else see this same problem? Or, more important, does anybody NOT see it on a 1080p TV? That would give me hope that a receiver swap or software update could cure it.


----------



## Jnel (Jan 17, 2006)

I have the same TV with the 622 (HDMI), and no problems with SD or HD displaying 1080i or 720p.


----------



## Andy Smith (Mar 1, 2006)

podder320 said:


> I have a Samsung 1080p DLP TV (model HL-S6187W) and the 622 receiver. Using either HDMI or component, I see something bad on non-HD channels.
> 
> The problem is this: non-HD satellite channels are deinterlaced wrong. The even/odd lines are inverted, displayed as odd/even. It happens everywhere, on every non-HD channel, and it is obvious with non-moving high-contrast curved shapes, like the Comedy Central logo in the corner of the screen.
> 
> ...


HLS6188W here and no problems in 720p or 1080i.


----------



## podder320 (Mar 4, 2007)

As a followup on the original problem, I tried the same 622 at Circuit City on a Sony HDTV using some recorded content I had, and the sales guy and I saw exactly the same behavior on that TV and he agreed it's wrong. Either there is something wrong with my particular receiver, or wrong with many 622's near my software level, or (unlikely) a TV problem that's common to both Samsung and Sony.

I'm attaching the "bad" Comedy Central image to this message - we'll see if the forum lets me post it. If a close look at your Comedy Central logo shows smooth curves without noticeable horizontal banding, you don't have this problem. To review: the TV is native 1080p; the same thing happens on HDMI or component; those bands appear only for non-HD channels; and they disappear when I set the 622 to 720p or 480p or 480i.


----------



## renpar61 (Aug 5, 2006)

I have a JVC HD-P61R1U 1080p TV and I see the same exact problem. I always thought it was the TV and posted on AVS forum in the specific TV model thread. No answers, I was contemplating calling JVC service. If this happens on other sets, it may very well be the 622, not the TV.


----------



## DP1 (Sep 16, 2002)

Thats weird.

I know it's not the same thing but it reminds of the old 6000 HD receiver.

When you had it set to 1080i output but were viewing a 720p channel, many people initially complained that there was weird "jaggies" in the image where the picture wasnt "lined up" correctly. But that reciever had a picture centering option and all it took to was a one time couple adjustment clicks one way or the other which lined everything back up and cured the problem.


----------



## podder320 (Mar 4, 2007)

renpar61 said:


> I have a JVC HD-P61R1U 1080p TV and I see the same exact problem. ... If this happens on other sets, it may very well be the 622, not the TV.


Thanks for the confirmation. It definitely happens on other sets: both my Samsung and a Sony at Circuit City, and only on 1080i output of a non-HD channel.

My next move is to take my 622 down to the place where the local service people come from and have them look at the image (hope they have an HDTV) and try other 622s to see if they look the same.

Whether it is in all 622s or just a fraction, it's a major software bug and could account for a lot of the "SD channels look bad" complaints from users. You need a big TV and sharp eyes to distinguish this problem from general "bad picture quality" complaints, and you need persistence to get past the usual explanations like "All SD looks bad on HD" and "1080i is interlaced so that's what you get." E* needs to see that this is real, distinct from other SD/HD problems, and fixable.


----------



## Ron Barry (Dec 10, 2002)

Very interesting Podder... Are you seeing this an all SD channels or just some in particular. I am sure some people will take a closer look and see if they see the same thing.


----------



## podder320 (Mar 4, 2007)

Ron Barry said:


> Very interesting Podder... Are you seeing this an all SD channels or just some in particular.


All SD channels. It's more obvious with certain types of content, but once you know what to look for you can see it's the same on all SD channels.

It is possible that this accounts for a proportion of "Poor SD quality" complaints coming from they'people with 1080-size displays. If setting the 622 to 720p instead of 1080i actually *improves* the sharpness of text on CNN or smooths out the curves in the Comedy Central logo, you're seeing this problem.

And again, I would love to hear from 1080-size TV owners who do *not* see a difference between 1080i and 720p in the smoothness of the Comedy Central logo's curves: that would give me hope that a replacement 622 could improve things. Thanks.


----------



## Ron Barry (Dec 10, 2002)

I don't have a 1080p TV. But I do have a 60" 1080i set that I will take a look at tonight if I can remember.


----------



## DP1 (Sep 16, 2002)

Well I have a FP throwing on to a 100" 16x9 screen that can sync to 1080i and 720p and when I look at SD channels via Component I dont notice such a thing. I just tried it by swapping between the 2 on various SD channels including CC and one of the ESPN Alt feeds that has the large stationary, circular, Dish logo. They all look basically the same in either 720p or 1080i.

So maybe it's only a factor when dealing with some 1080p circuitry.. de-interlacing/upconverting. That would explain why it's not talked about much. Comparatively, most people dont have sets capable of 1080p. Upconverting to it or accepting it natively from whatever sources.


----------



## rgriffith (Jan 21, 2007)

I have a 50" Samsung 1080P DLP (Model HL-S5087) and I do not see any significant difference between the Comedy Central logo or anything else on the screen whether I switch to 1080i, 720p, or 480p. It looks pretty jagged no matter what. 

I haven't seen different HD/SD comparisons (using D* or cable) to know if this is an E* problem or just the "SD channels look bad" problem you mention above. I'm an HD newbie, so I had always just assumed changing a 480 line resolution to 1080 would necessarily lead to poor resolution. Like zooming a jpg image on the computer to 200% size.

If I could get a better picture by using the 720p resolution mode, and my 622 was working fine otherwise, I'd be reluctant to swap in a new one hoping for better. Switching to 1080i for the occasional (?) HD event that looks better in that mode is a hassle, but a rather minor one IMHO. Just a few clicks of the remote.


----------



## Mark Lamutt (Mar 24, 2002)

Podder - please post a picture of the Comedy Central icon with your 622 set to 720p so that I can directly see the difference you're seeing.


----------



## Ron Barry (Dec 10, 2002)

Try here Mark http://www.bestbits.org/dish. Podder provided the link and I removed it since a poster indicated it my be suspect. I went there after podder replied and it seems fine.


----------



## Mark Lamutt (Mar 24, 2002)

Hmmm...


----------



## Mr.72 (Feb 2, 2007)

that might not be a deinterlace problem at all. It might be a field-rate conversion problem. Like you set the box to 1080i and it sends the frames like 1a 1b 2a 2b etc. at 60 Hz and your TV is doing a conversion to 24fps "1080p" and ends up de-interlacing it wrong.

It looks a lot like the example of the 3:2 pull-down issue on this page:

http://www.gnss.com/tch_dcdi_overview.phtml


----------



## harsh (Jun 15, 2003)

While it is ugly, I don't think this is symptomatic of a problem. That's just what happens when a 1080p trys to display a 320x240 TV image.

You might check to see what happens if you turn all of the noise correction and picture enhancement functions the other way.


----------



## podder320 (Mar 4, 2007)

Mr.72 said:


> that might not be a deinterlace problem at all. It might be a field-rate conversion problem. Like you set the box to 1080i and it sends the frames like 1a 1b 2a 2b etc. at 60 Hz and your TV is doing a conversion to 24fps "1080p" and ends up de-interlacing it wrong.
> 
> It looks a lot like the example of the 3:2 pull-down issue on this page:
> 
> http://www.gnss.com/tch_dcdi_overview.phtml


Thanks for the analysis, but I can't agree. Field conversion and frame-rate/pulldown problems like that show up in moving images, because the interlaced lines are offset both in space and in time. For an unmoving part of the image like the Comedy Central logo overlay, those effects don't cause any horizontal banding artifacts.

At 1080i, the 622 is putting out 1a 2a 3a 4a followed by 1b 2b 3b 4b, and the TV needs to reassemble these into 1a 1b 2a 2b 3a 3b 4a 4b. (You can also think of this as putting out lines 1-3-5-7 followed by 2-4-6-8.) My TV does the reassembly perfectly well when viewing an HD channel from the 622, so I don't think it's a problem with the TV processing the 1080i signal into its native 1080p display resolution.

Also: an interlacing artifact at 1080i would show up at about 36 lines per inch on my display, which is 30" high. But the horizontal artifacts in the Comedy Cental logo are much closer to the 480 resolution of 16 lines per inch (total 32 lines for the 2" captured in my picture). This indicates that the problem lies in the 622's upconversion from the SD MPEG data to the 1080-size image buffer, not in the transmission of that image buffer (at 1080i) to my TV, or my TV's decoding of the 1080i fields to 1080p frames. (Overscan makes these numbers approximate, but within 5% or so.)

I'm attaching two new pictures to this message, showing part of a bicycle tire from an American Express ad. This crop is about 2" high on the screen, as before. The "bad" one is with the 622 set at 1080i; the "good" one is at 720p. As with the Comedy Central logo, I believe the one at 1080i has all the same data, but the original 480 scan lines were put into the image buffer in the wrong order. If you swapped each pair of lines I think the image would reassemble perfectly.


----------



## caseystone (Feb 21, 2006)

Sorry to report that I have this also.

I have a Samsung HLS 1080p set and it exhibits this issue just like you posted (I did not actually check to see if it looks better on 720p though). I'm not sure if it has always been this way or if perhaps a SW update caused it.

I do recall noticing a 'line-y' appearance one day on Comedy Central (one of the few non-HD channels I watch)... I'm glad you pointed it out and have documented it.

I have the signal multed on component to another display.. I'll check that one and get back to you.

-Casey


----------



## lujan (Feb 10, 2004)

podder320 said:


> ... The "bad" one is with the 622 set at 1080i; the "good" one is at 720p. ...


There's a good one?


----------



## Mr.72 (Feb 2, 2007)

alright, podder320 you make an excellent case  But I still don't think with a still image you are seeing an interlace problem. Mostly because with a still image, a reversed-field our field-out-of-order problem would not appear like this. In fact you would not see it at all. Like you said, you would only see this on moving images. Since it's a still image, getting them out of order wouldn't matter. You would only notice they are out of order when the image moved.

It actually looks to me like a horizontal alignment problem with the fields, where if the fields are 1a 1b 2a 2b etc you are seeing all of the "b's" offset to the right, and all of the "a's" offset to the left, or something like that. 

I am sure there are many opportunities for up-conversion errors in the 622. If it is an up-conversion error, then it is true that native pass-thru would just fix it (or at least, make it a problem for the TV to deal with).


----------



## Mark Lamutt (Mar 24, 2002)

podder, I've reported this through the beta channels for you.


----------



## koralis (Aug 10, 2005)

I kinda-sorta see that on my 921 set to 1080i for my samsung 1080p tv as well. It's not as pronounced (probably because of the TV tweaking I've done for calibration), but believe that it's there.

Probably a better example would be the rare advertisement shot in clearly 480i NTSC which crawls horribly on my tv. The horizontal lines visibly shift and sway.


----------



## renpar61 (Aug 5, 2006)

I am glad we started this thread. All the technical explanations are very valuable, I didn't expect to see so much detailed information on this topic. Although there seem to be difference of opinions on the cause, it's fair to assume that the problem lies with the 622. And it sounds like it should be a correctable one (software?). Can we take this to Dish so they can look into it?


----------



## Ron Barry (Dec 10, 2002)

Look up two posts renpar61. Mark has brought it to Dish's attention through the Beta channels so I am pretty sure it has been brought to Dish's Engineering team.


----------



## caseystone (Feb 21, 2006)

caseystone said:


> I have the signal multed on component to another display.. I'll check that one and get back to you.


Following up... It is harder to discern on the other set due to analog connection and long cable run, but I think I see it on that display also (1080i component out ---> scaler outputting progressive scan computer resolution on VGA ---> computer LCD display).

This has probably been noted, but when you pause the DVR the jagged-ness is much worse, so we are getting more lines when it's rolling but I think it is a de-interlacing problem.

I did check the PQ with 622 set to 720p and it does look much better.

-Casey


----------



## Ron Barry (Dec 10, 2002)

Ok.. I have looked a few times over the last week to see if I see this issue with my 1080i set Sony LCD Grand Wega II and I don't see it. Be curious if anyone with a 1080i or 720p set sees it?


----------



## podder320 (Mar 4, 2007)

A month ago I started a thread about a quality problem when watching SD channels with the 622 set to 1080i. The short version is that the 480 lines of SD data seem to be put into the 1080-size image buffer in the wrong order. You can read more about it here:http://www.dbstalk.com/showthread.php?t=81461​Well, last night I had a breakthrough! It explains why not everybody is seeing this and how anybody who does see it can make it go away.

* The answer: *this only happens in "single mode," and only when using the TV2 decoder to feed your HDTV. To switch to the (good) TV1 decoder, *press SWAP.*

That's it. See, there are two MPEG decoders in the 622. In dual mode these feed the two TVs you can attach, TV1 and TV2. In single mode the two decoders let you use picture-in-picture. Surprisingly, the two decoders aren't running the same software or firmware. One of them has the line-order problem, and the other doesn't. (As far as I can tell the two decoders are otherwise identical, and except for this problem you wouldn't know or care which one you were using in single mode.)

Try it yourself: I find I can demnstrate this most easily on channels with unmoving text surrounding the moving pictures, like you get on HNN on 202 or QVC on 226. Or go to Comedy Central and look at the curves in the logo in the lower right corner.

Set your 622 to "single mode" and go to an SD channel. Now press "SWAP" and tune the *other* decoder to the same channel. (Don't use PIP, just SWAP.) Once they're both on the same channel, you can use SWAP to switch quickly between decoders. On one, the text and curves in the graphics will have fuzzy edges and have visible gaps and horizontal line artifacts. On the other, the text will look fine - as good as 480-pixel text should look on a 1080-resoluiton HDTV.

The internal decoder that has this problem appears to be the one that feeds "TV2" when in Dual Mode, so you'll never see this problem if you don't use Single Mode, or if you have never used SWAP. If you do use SWAP, you have about a 50-50 chance depending on which tuner you ended up on the last time you were swapping between them. But now you know how to recover your SD quality if you see this problem: SWAP back to the TV1 decoder.

I sent this report to [email protected] last night and got a reply this morning. I hope that these details will help them address the problem in a future release. (Right now they say they're working on higher-priority bugs, which I understand completely. Now that I know how to make this problem go away, it has very low priority for me personally.)


----------



## Ron Barry (Dec 10, 2002)

Cool. Podder320... I actually have not seen this on my installation but perhaps I just did not notice it. Others that are seeing this please try what podder320 suggested and provide feedback. If this workarounds works for others, this is truly an excellent find and is what this forum is all about. Kudos Podder. Excellent Post. :biggthump :icon_hroc


----------



## BobaBird (Mar 31, 2002)

Can this solution be merged with the problem thread referred to in post #1?


----------



## podder320 (Mar 4, 2007)

I found out more information about this and a partial solution. It also explains why some people see this and some do not. See the new thread http://www.dbstalk.com/showthread.php?t=85251 for details.

The short answer is to use the SWAP button. The SD line-order problem only happens in Single Mode, and only on one of the two software tuners/decoders in the 622. In single mode, tune to an SD channel, then hit the SWAP button and tune that same channel on the other tuner/decoder. If you swap back and forth you'll see that one shows this line-order problem and the other does not.


----------



## podder320 (Mar 4, 2007)

Good idea. I just posted a quick summary in that thread with a link to this one. (If that's bad then some admin can close this thread or whatever.) I wanted to announce the solution with a new thread name (including SOLVED!), that's why I started a new thread.


----------



## wje (Mar 8, 2006)

I haven't seen this before. I tried the test, both images appear identical. I've always used single mode and 1080i output, and I use swap all the time. My TV is native 720P; perhaps its deinterlacer is cleaning up the problem?

Postnote: I just went and read some of the other thread, and I see you have a 1080P set. Has it been determined that anyone using a 1080P display has the problem, or is it some kind of interaction between the 622 and some 1080P sets? I'm concerned because I'm thinking about getting a 1080P TV soon.


----------



## Will Munshower (Mar 4, 2007)

wje said:


> Postnote: I just went and read some of the other thread, and I see you have a 1080P set. Has it been determined that anyone using a 1080P display has the problem, or is it some kind of interaction between the 622 and some 1080P sets? I'm concerned because I'm thinking about getting a 1080P TV soon.


I have a 1080p set and I cannot see a bit of difference. As soon as I read the first post I ran to check it out. I even called in the Mrs., who has a very discerning eye. (She's a good egg, who totally supports my HT addiction  ). I checked this with several different channels. I also paused on frames with a lot of text. For the life of me, they look identical.

There has to be some other parameter that I am missing. I just can't see the difference. Or it must be set related...Will


----------



## Mike D-CO5 (Mar 12, 2003)

Set related I am thinking. I see no difference in dual mode or single mode at all.


----------



## Rob Glasser (Feb 22, 2005)

I just tried this myself on my 43" Pioneer plasma and saw no difference between the 2.


----------



## Ron Barry (Dec 10, 2002)

I tried this last night on my Sony GWII 60" at about 3' and I could not see any difference.. Must be more to this mystery. I also combined the threads as suggested by BobaBird.


----------



## DarkSol (Feb 11, 2007)

I have the JVC 70FH96. I noticed the same thing last year and still see it on the current firmware (4.03). I've had two different 622s and both show it.


----------



## podder320 (Mar 4, 2007)

Very interesting. I'm surprised to hear that some people with 1080-resolution displays are seeing this and others are not. (I'm not surprised it doesn't show up on a 720-resolution display even when it's driven at 1080i -- the downscaling/pixel averaging being done by the display will mask problems like this.)

Well, for everybody who *does* see it, I'm pleased to offer the SWAP solution. For everybody else, I guess you live a charmed life and got a "lucky" 622.


----------



## koralis (Aug 10, 2005)

Those saying you have a 1080p display... do you have a 1080i input with the DLP 1080p chip? (it doesn't have 1080 lines of unique resolution... it reuses 540 to show to two different areas of the screen.)

If this supposition is corrent, then for LCD 1080p (either direct or rear projection) it won't matter because each pixel is uniquely addressable.

I have a 1080p samsung dlp but haven't had a chance to try it yet to verify.


----------



## harsh (Jun 15, 2003)

koralis said:


> Those saying you have a 1080p display... do you have a 1080i input with the DLP 1080p chip? (it doesn't have 1080 lines of unique resolution... it reuses 540 to show to two different areas of the screen.)


1080p DLP is actually 960x1080. Do a web search for "wobulation".

DLP is probably not a good example of a technology for identifying artifacting given its color wheel and wobulation complications.


----------



## podder320 (Mar 4, 2007)

harsh said:


> 1080p DLP is actually 960x1080.


Right. The poster who said a 1080p display with a 1080i input only has 540 lines of resolution is mistaken. The DLP chip delivers 960 dots horizontally, and the display system uses "wobulation" (rapid horizontal image shifting) to double the horizontal resolution. It is intended to happen so fast you can't see it, but even if you could, it wouldn't cause a problem with *vertical *line ordering like I'm describing in this thread.

Also remember, I took the same 622 to a Circuit City store and tried it on a Sony XSRD display, a three-LCD fixed-pixel rear projector with no color wheel or wobulation. The store clerk and I saw exactly the same defect in the image on that display.

The fact that some people see this and some don't means there must be more to this than has come to light so far. The single/dual mode "swap" trick was a big step in understanding that, but even then some people apparently aren't seeing it on *either* decoder. I don't consider the bands in the Comedy Central logo to be a subtle defect; on a big-enough display I think it would be hard to miss, especially when using "swap" to see the difference between "good" and "bad."

So: if you have a 1080-resolution display at 60" or larger, and your 622 is set to 1080i, and you do the "swap" trick, and you still do not see bands in your Comedy Central logo, that makes you the "wildcard" that is not explained by the current theory. It also makes you lucky because you don't have to fiddle your 622 to get good SD picture quality like I do - and like the others on this forum who also see this.


----------



## Mr.72 (Feb 2, 2007)

Sure is a lot of unfounded speculation in this thread. Like, the two channels using different firmware. They are the same hardware device (same chipset) AFAIK. It's not two separate pieces of silicon, but one chipset that supports dual-channel.

It seems the only thing that's _clear_ is that whatever the problem is, it's only related to specific tv sets. That points to a compatibility problem more than anything. What would be interesting to me is whether these same sets have reports of a similar problem from other sources like cable boxes, blu-ray players, upconverting dvd players, etc. Maybe searching avsforum would be a good idea.


----------



## rickz (Mar 18, 2003)

Mr.72 said:


> It seems the only thing that's _clear_ is that whatever the problem is, it's only related to specific tv sets. That points to a compatibility problem more than anything.


I'll add my fuel to the fire. After following this thread and searching elsewhere, I'm doubtful on your point. The theory presented by *podder320* appears solid.

I upgraded to a Samsung HL-S5087W and ViP622 this month, with the 622 in single-mode operation and 1080i output. I decided to compare the two tuners with Swap, both showing Food Network with its round logo, and one tuner noticeably exhibits the decoder issue while the other does not.

Practically speaking, however, my family members probably don't see this particular problem most of the time. Compression artifacts and posterization are noticeable above all else, and we long ago resigned ourselves to accepting these issues in DBS, especially from distant locals.

Perhaps we'll see a fix someday, but I'm not holding my breath.


----------

