Re: HD picture not even close to HD - too much compression

pulseman · ‎07-14-2009

Hi erazoner,

If you are happy with the HD quality please keep it! For me, HD on uverse is not good enough since I have seen much better. What else can I say...

texasguy37 · ‎05-18-2009

pulseman wrote:
Hi erazoner,

If you are happy with the HD quality please keep it! For me, HD on uverse is not good enough since I have seen much better. What else can I say...

Well, you have to go with the TV service that makes you happy. If that service is not U-verse, so be it.

squareeyes · ‎11-07-2008

most likely not a regional issue then, as i'm also on cox cable in downtown san diego. i did have a chance to compare while i had both services on my older (relatively speaking) jvc 46" lcd 1080p set. while both showed artifacts, the cox cable pq blew uverse out of the water. uverse was softer, less detailed, and displayed severe pixel jumping on still, textured images, and it showed more and frequent motion artifacts then cable. standard dvd was much better then uv and cable w/o any artifacts at all, and blu-ray pq, of course, was best of all-- crystal clear.

i wonder if it's how each brand tv's image processor is handling the uv-compressed video signal? or if different tvs' proprietary "video smoothing" or "image stabilization" accounts for skewed pq results among users? either way, i have to deduce that it's the uv video signal in my home, as all other signals into my tv displayed much better results.

erazoner wrote:
fl_cyclist wrote:
It is interesting that there is a wide range of views on UV PQ. I watch a lot of HD, I have had OTA, Cable and I watch Blu-Ray. My PQ with UV is on par with what I was getting from cable and slightly less crisp than OTA. But certainly I get no motion artifacts and no pixelation. Living in S. Fl weather issues (lot of wind and strong rain) constantly affected both my OTA and Cable picture. I have had no weather related issues with UV. I am very happy with the PQ, so I guess my advice would be that you need to try it and not just read individual complaints or cudos. Also don't understand how if this was due to compression that everyone would not be saying the same thing.
I also live in San Diego (the city, not northern burbs), and my experience is the same as fl_cyclist, except I have had Cox and DISH for comparison. Granted, I haven't watched them side-by-side, but I don't see any of the problems mentioned on my Toshiba Regza.

texasguy37 · ‎05-18-2009

squareeyes wrote:
most likely not a regional issue then, as i'm also on cox cable in downtown san diego. i did have a chance to compare while i had both services on my older (relatively speaking) jvc 46" lcd 1080p set. while both showed artifacts, the cox cable pq blew uverse out of the water. uverse was softer, less detailed, and displayed severe pixel jumping on still, textured images, and it showed more and frequent motion artifacts then cable. standard dvd was much better then uv and cable w/o any artifacts at all, and blu-ray pq, of course, was best of all-- crystal clear.
i wonder if it's how each brand tv's image processor is handling the uv-compressed video signal? or if different tvs' proprietary "video smoothing" or "image stabilization" accounts for skewed pq results among users? either way, i have to deduce that it's the uv video signal in my home, as all other signals into my tv displayed much better results.

It could be related to the type of television. I have three Sony HDTV's connected with HDMI cables. I get good HD pictures quality, which compares favorably with the HD quality that I got with Dish Network. There could be some other environmental factors, but who knows.

CGI_1 · ‎07-29-2008

squareeyes wrote:
most likely not a regional issue then, as i'm also on cox cable in downtown san diego. i did have a chance to compare while i had both services on my older (relatively speaking) jvc 46" lcd 1080p set. while both showed artifacts, the cox cable pq blew uverse out of the water. uverse was softer, less detailed, and displayed severe pixel jumping on still, textured images, and it showed more and frequent motion artifacts then cable. standard dvd was much better then uv and cable w/o any artifacts at all, and blu-ray pq, of course, was best of all-- crystal clear.
i wonder if it's how each brand tv's image processor is handling the uv-compressed video signal? or if different tvs' proprietary "video smoothing" or "image stabilization" accounts for skewed pq results among users? either way, i have to deduce that it's the uv video signal in my home, as all other signals into my tv displayed much better results.

I have my doubts its the tv, although some could probably hide the compression artifacts better than others . At any rate there is aggressive compression - thats a fact.

I have a Toshiba, a Sony, a WestingHouse, and a SHARP and all looked better with Charter cable . I had the SHARP and SONY lcd's also with Direct which was also better. According to the tech's my signal is great, theres practically no interference, stats are pristine and I am about 1700 ft from the vrad. For me its hard to put the blame on the tv's when I have 4 different models that all showed better HD PQ from other subscribers.

Message Edited by CGI on 07-16-2009 09:49 AM

pulseman · ‎07-14-2009

I did all that. I removed all image enhancement features(DNI, 120Hz, itc) on my Samsung and I still see the same compression artifacts. I doubt the problem is the TV since it outputs outstanding pictures from my PS3 to begin with

All those artifacts are known to occur when aggressive compression is in place usually because of low bandwidth, which is exactly what ATT does. I wish Verizon FIOS was in my neigborhood

texasguy37 · ‎05-18-2009

Hopefully in the not to distance future, AT&T will find a away to provide everyone with a bigger pipe and will compress the picture less to improve the quality for everyone.

joglys · ‎09-03-2008

I agree with pulseman. I just ordered service on 7/12 and the HD PQ is aweful. I get compression artifacts on my 52 inch Samsung LCD. Comcast was much sharper on the same TV with the same settings. I'm 2700 feet from the VRAD and I am under the 2HD/2SD profile. Called ATT for technical support and they sent a premise tech. Premise tech arrived today 7/15 and he said that the line was fine and should be getting a crisp image. As soon as he saw the HDNET channel he noticed the artifacts, and mentioned to me that this was a known issue with alot of costumers and ATT was working in sending an upgraded software to all receivers within the next 10 days. I'm not sure if told me this because he was in a hurry, or if he was telling the truth. But, what would an upgraded software on the receiver do to the image? I thought that compression was done somewhere else. I have changed cables HDMI to Component and still the same. I have switch the second receiver on the other room with the DVR and it's the same. I have searched everywhere online, but I am always getting different stories. The TV, the line, the RG, the distance, etc.. Can some one here tell me, what is the reason for having pixelation issues, compression artifacts and mediocre HD quality?

SomeJoe7777 · ‎01-30-2008

mibrnsurg wrote:

If you have an LCD built more than a year ago, you might not have a fast enough motion engine to keep up w/the motion.

Chris,

I'm not sure if you were serious or just joking with that comment, but I just wanted to clarify to anyone else who might be reading that the TV's motion engine has absolutely nothing to do with compression artifacts, it cannot and could not correct any artifacts if present, and is in nearly all cases completely unnecessary.

A light amount of motion interpolation can make 24 fps movies from DVD or Blu-Ray look smoother, but 240 Hz and 480 Hz motion interpolation features are virtually completely useless. None of that motion interpolation is even visible to the eye, and makes the picture look artificial anyway. Plus many TVs introduce their own set of artifacts when the motion interpolation is turned on, on top of the compression artifacts already present.

Anyone out there who has a TV that does not do motion interpolation is not missing anything. You don't need it, so don't worry about it. And it certainly won't magically correct any compression artifact issues.

texasguy37 · ‎05-18-2009

Why do some users have better HD picture quality than others? If we eliminate the TV being the issue, what other factors are involved?

pulseman · ‎07-14-2009

texasguy37,

How far do you seat to watch TV? If you are 13-15 feet away then you will probably not notice any of the artifacts allthough you can clearly see that the background objects like trees or dark scenes getting blurried and their color softened. However, go closer to the screen, between 5-7 feet(based on how big your TV is of course) and sit there, watch a minute and you are going to start noticing that the HD picture is a glorified artifact city. One example is to look at human faces. You will see that their skin is getting blurred at some spots, like they intentionally smothered themselves with way too much makeup to hide every single wrinkle they have. Another example is the grass in football games, which becomes one big messy green color and you cannot see any details on the grass. Another example is to look at the edges of objects and you will see that they look less defined, blocky.

In fact, I was so bothered by the compression artifacts that I had to move my screen far away from my couch in order to stop noticing them. Of course, the reason people buy big HDTVs is so that they can enjoy the HD picture to its fullest but if you have to move the TV back in order to make it look decent, then you lost the main point of HD; clarity and sharpness.

As we have already discussed, the main reason all those artifacts are there is because the bandwidth is too low to produce a nice crisp HD picture all the time. Sometimes the picture looks good, but usually it is because the camera is not moving and the bitrate has the time to put some of the details into the picture. But most of the time, the camera is moving, and when that happens, the bitrate is too low to catch up with all that data that needs to be transmitted per frame in order to produce all the details on the picture. To see how much data is rendered per frame, press the "pause" button and you will see that the still picture misses a lot of details.

Message Edited by pulseman on 07-15-2009 10:20 PM

spd2demun · ‎07-28-2007

Distance           Minimum size               Maximum size
6 feet               24-inch screen             36-inch screen
8 feet               32-inch screen             48-inch screen
10 feet             40-inch screen             60-inch screen
12 feet             48-inch screen             72-inch screen

or per Amazon:

Distance           Minimum size             Maximum size
6 feet               24-inch screen             48-inch screen
8 feet               32-inch screen             64-inch screen
10 feet             40-inch screen             80-inch screen
12 feet             48-inch screen             96-inch screen

Could different types/brands of cables cause different PQs?

texasguy37 · ‎05-18-2009

pulseman,

Thanks for the info.

I have a 46 inch Sony HDTV and I sit 7 feet from the screen. My HD picture quality compares favorably with what I had with Dish Network. It is not as good as what I can get with an OTA signal, but the quality is good.

randyl · ‎10-25-2007

texasguy37 wrote:
pulseman,

Thanks for the info.

I have a 46 inch Sony HDTV and I sit 7 feet from the screen. My HD picture quality compares favorably with what I had with Dish Network. It is not as good as what I can get with an OTA signal, but the quality is good.

fwiw a lot has to do with the stations being watched etc

its a variable bit rate and can vary a lot..........

fwiw check out the diff sations and the amount of band ...

my slant

randy

oz_1 · ‎10-25-2008

So reading this it would seem that different areas are getting different quality PQ and not everyone is on the same page but that does not surprise me since my PQ quality with Comcast was sub-par but one of my co-workers across town had a great picture there are so many varibles that can

happen I just got tired of paying Cadillac prices for a Nova ride.

CGI_1 · ‎07-29-2008

SomeJoe7777 wrote:
mibrnsurg wrote:
If you have an LCD built more than a year ago, you might not have a fast enough motion engine to keep up w/the motion.

Chris,

I'm not sure if you were serious or just joking with that comment, but I just wanted to clarify to anyone else who might be reading that the TV's motion engine has absolutely nothing to do with compression artifacts, it cannot and could not correct any artifacts if present, and is in nearly all cases completely unnecessary.

A light amount of motion interpolation can make 24 fps movies from DVD or Blu-Ray look smoother, but 240 Hz and 480 Hz motion interpolation features are virtually completely useless. None of that motion interpolation is even visible to the eye, and makes the picture look artificial anyway. Plus many TVs introduce their own set of artifacts when the motion interpolation is turned on, on top of the compression artifacts already present.

Anyone out there who has a TV that does not do motion interpolation is not missing anything. You don't need it, so don't worry about it. And it certainly won't magically correct any compression artifact issues.

Thanks for the explanation!

Sounds to me like a marketing ploy since every tv maker out there now aggresively markets this feature.

mibrnsurg · ‎07-15-2008

SomeJoe7777 wrote:

mibrnsurg wrote:
If you have an LCD built more than a year ago, you might not have a fast enough motion engine to keep up w/the motion.

Chris,

I'm not sure if you were serious or just joking with that comment, but I just wanted to clarify to anyone else who might be reading that the TV's motion engine has absolutely nothing to do with compression artifacts, it cannot and could not correct any artifacts if present, and is in nearly all cases completely unnecessary.

A light amount of motion interpolation can make 24 fps movies from DVD or Blu-Ray look smoother, but 240 Hz and 480 Hz motion interpolation features are virtually completely useless. None of that motion interpolation is even visible to the eye, and makes the picture look artificial anyway. Plus many TVs introduce their own set of artifacts when the motion interpolation is turned on, on top of the compression artifacts already present.

Anyone out there who has a TV that does not do motion interpolation is not missing anything. You don't need it, so don't worry about it. And it certainly won't magically correct any compression artifact issues.

No, he was specifically complaining about motion problems during auto racing SomeJoe and that will be affected

by the motion engine in any TV, did not say it would affect compression artifacts.

Chris

Please NO SD stretch-o-vision or 480 SD HD Channels
1-800-983-2811 to avoid Mr. Voice Recognition
YRMV IMHO Simply a U-verse user, nothing more

SomeJoe7777 · ‎01-30-2008

mibrnsurg wrote:

No, he was specifically complaining about motion problems during auto racing SomeJoe and that will be affected by the motion engine in any TV, did not say it would affect compression artifacts.

The motion artifacts he was complaining about are compression-algorithm induced, not the result of insufficient frame rate. Motion interpolation can only help insufficient frame rate, such as when fast action is filmed at 24 fps.

If he was watching live auto racing in HD, it was either 1080i/59.94 or 720p/59.94, both of which are updated 60 times per second (temporal resolution of 60 Hz). Motion interpolation is useless here.

The fast motion, however, overwhelms the compression algorithm, starving it for bitrate, and results in smeared/blocky details. This is the problem he was talking about, and no "motion engine" will help him.

awhited74 · ‎08-25-2007

I think that a spec that was got a lot of talk in the beginning of LCD's, but now is often overlooked is pixel response time(unrelated to refresh rate) which translates to the amount of time it takes a pixel to go from black-white-black. It is measured in milliseconds and the lower the number the better fast moving motion will look, the higher the number the more blurred fast motion will appear. But one caveat is that there is no industry standard for measuring response time so manufacturers can embellish there numbers to make them appear good. Also, on cheaper made panels the pixel response time can vary. So 8ms may not actually be 8ms.

IMHO

RCSMG · ‎12-10-2007

fwiw

SomeJoe7777 · ‎01-30-2008

awhited74 wrote:
I think that a spec that was got a lot of talk in the beginning of LCD's, but now is often overlooked is pixel response time(unrelated to refresh rate) which translates to the amount of time it takes a pixel to go from black-white-black. It is measured in milliseconds and the lower the number the better fast moving motion will look, the higher the number the more blurred fast motion will appear. But one caveat is that there is no industry standard for measuring response time so manufacturers can embellish there numbers to make them appear good. Also, on cheaper made panels the pixel response time can vary. So 8ms may not actually be 8ms.

On the subject of LCD pixel response time, this is the reason that to me, LCDs just don't look quite as good as other display technologies. To improve the pixel response time, what LCD manufacturers have done is place some logic into the LCD drive circuitry that "overdrives" the LCD element with a higher voltage than required.

Let's say a pixel needs to change luminance value (0=pure black, 255=pure white) from 50 in frame 1 to 90 in frame 2.

The circuitry will apply the equivalent voltage that corresponds to a luminance value of 255 to the LCD element. This causes the pixel to rapidly increase it's brightness. As the pixel element's brightness is passing through 90, the circuitry then immediately lowers the voltage to the corresponding value for a luminance of 90. Thus, the circuitry's "overdrive" logic has caused the pixel to change luminance from 50 to 90 much faster than it ordinarily would have.

The problem is that the overdrive, while it lowers the response times, also results in overshoot. The pixel's luminance value will actually overshoot the proper luminance of 90 up to a value of 100 or so, then begin to come down to the 90 value. In fact, the luminance will oscillate a few times around 90 as the voltage settles.

The net effect of all these pixels overshooting their intended luminance values from frame to frame is that the circuitry increases the noise in the picture. This overemphasizes film grain, and overemphasizes compression artifacts (mosquito noise). On other display technologies, a large area of similar color should have a very smooth gradient, but on an LCD display, a fair amount of pixel noise dances around inside the large area that should be smooth.

This is why I prefer CRT, plasma and LCoS display devices - they do not suffer from this problem.

fl_cyclist · ‎12-24-2008

Some additional info: I am watching on a 61" Samsung 1080p DLP and I sit about 6' from the screen. My connection is direct HDMI from the Cisco STB to the Tv, not running it through my AVR.

joglys · ‎09-03-2008

What does this have to do with the main subject here? Again, My 52 inch TV HD image was perfectly fine with Comcast (no dancing pixels), however with Uverse, it is a different story. Therefore, this rules out the TV!

pulseman · ‎07-14-2009

I agree with mrjr101.

A high quality picture can be generated on any HDTV type as long as the bitrate stream is high enough to fill the gaps on the 720p grid or 1080i for that matter. My PS3 produces amazing quality video playback and I have an LCD screen.

Some people say that the bitrate on UVERSE is between 5-7MBps. But I am not sure if that is true because when I go to the system information page on my UVERSE menu, I see that the Network Bps(Bits per second) is 314xxxx(dont remember the rest of the numbers), which is 3MBps. It really makes me wonder if the bitrate is always a constant(or maximum) 3MBps no matter how busy the scene is and thats why we see all those artifacts.

randyl · ‎10-25-2007

pulseman wrote:
I agree with mrjr101.

A high quality picture can be generated on any HDTV type as long as the bitrate stream is high enough to fill the gaps on the 720p grid or 1080i for that matter. My PS3 produces amazing quality video playback and I have an LCD screen.

Some people say that the bitrate on UVERSE is between 5-7MBps. But I am not sure if that is true because when I go to the system information page on my UVERSE menu, I see that the Network Bps(Bits per second) is 314xxxx(dont remember the rest of the numbers), which is 3MBps. It really makes me wonder if the bitrate is always a constant(or maximum) 3MBps no matter how busy the scene is and thats why we see all those artifacts.

did u just ignore this one >>>>> link

its variable fwiw

randy

joglys · ‎09-03-2008

Additional Info - Because I was too focused on HD channels to check on the artifacts issue, I did not notice that they exists on the SD channels as well, and they are worst than the HD ones. If it was a compression issue, shouldn't I get alot less artifacts on the SD channels? It's totally the opposite. This is driving me nuts.

pulseman · ‎07-14-2009

I saw them too on my HDTV but its been a while since I watched SD feed so I didn't really bother. However, I have an SDTV in my bedroom and the artifacts, although there, are less noticeable because of the low resolution and the interlacing that occurs on SDTVs. Because of those factors, they can increase the compression and think it will go unnoticed on people's eyes who have SDTVs. But clearly this is not the case when you watch SD feed on HDTVs .

It doesn't matter what feed ATT Uverse is showing, there is always compression involved in the picture in order to save bandwidth at the end of the day.

Message Edited by pulseman on 07-16-2009 05:45 PM

Message Edited by pulseman on 07-16-2009 05:48 PM

SomeJoe7777 · ‎01-30-2008

pulseman wrote:

Some people say that the bitrate on UVERSE is between 5-7MBps. But I am not sure if that is true because when I go to the system information page on my UVERSE menu, I see that the Network Bps(Bits per second) is 314xxxx(dont remember the rest of the numbers), which is 3MBps. It really makes me wonder if the bitrate is always a constant(or maximum) 3MBps no matter how busy the scene is and thats why we see all those artifacts.

The HD channel bitrate is indeed VBR (Variable Bit Rate) between 5 and 7 Mbps per channel. This is megabits, (small b), by the way.

The number in the U-Verse System Information menu is 3145728 MBps. This is megabytes, (capital B). If you multiply it out, 3145728 * 8 = 25,165,824 Mbps, which is your profile rate. This is just telling you the maximum possible data rate over your VDSL connection, and has nothing to do with the actual channel bitrate.

I continually measure and graph my bitrates on my system. Check out my channel bitrate graphs to see the numbers.

Message Edited by SomeJoe7777 on 07-16-2009 10:02 PM

pulseman · ‎07-14-2009

SomeJoe7777,

Thanks for the clarification. That actually makes sense.

Randyl,

I couldn't test the link you provided earlier because I was at work. But you are right. I went to the link and it is a variable rate.

Message Edited by pulseman on 07-16-2009 08:20 PM

callmeox · ‎08-30-2007

SD channels will always look worse on an HD LCD than on a SD CRT or LCD.

LCD's are designed to run at a specific resolution and any time you go outside of the native resolution, the picture quality suffers and sharpness declines.

If you have an LCD monitor on your computer, try changing the screen resolution to a number of the different options and observe the difference in quality. You should see the fuzziness appear especially if you pick a resolution below the native resolution of the monitor.

480i standard def on a 720 or 1080 screen is the same type of mismatch.

Uverse SD on our old 32" CRT was stellar...it kicked DirecTV's butt 8 ways from Sunday,