One of my locals picture size has shrunk, Why?
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I think your picture is small because you paid your bill late. Pay your bill on time and Dish will send you the whole picture.
I think hendrix04 may be on to the issue"Now, as far as what you're seeing... somewhere a downconverter is set to letterbox. The problem with this is when you letterbox a 4x3 program (many commercials, all soap operas, some other shows), you end up putting black bars on all four sides. If you watch a 4x3 program on a 16x9 set, you should have black bars on the left and right. But keep in mind, the "letterbox" setting on the downconverter shows EVERYTHING from the original 16x9 image... in this case, including the black bars on the left & right. So now you see black bars on all four sides... also known as "postage stamp". The problem is with either dish or the local. Just to clarify , I get a postage stamp picture on both my 4x3's and my 16x9's when I watch a show such as seinfeld on any receiver.
I was also able to scan ch 55 in from cox cable and compare to the dish feed on the same TV, and the picture is normal not postage size like dish. I'm leaning towards the local channel being the problem, after all it's the CW network maybe they don't have enough money for the proper equipment. All my other locals are normal.
Just because your other locals are normal doesn't mean the problem is at the station. Dish has a receiver for every station in the market. Assuming you're watching an SD version of the station, Dish downconverts the signal. THAT'S where it sounds like the problem is. Comparing the same channel on cable vs. satellite shows the problem on Dish only, right? THAT points to Dish right there.
Here's what (I think) is happening... let's use Seinfeld as an example. The show is 4:3. If you use OTA to watch the show (using an ATSC tuner), the show would fill a 4:3 set and you'd have black bars left & right on a 16:9 set (barring 'zooming' or otherwise messing with the picture).
The TV station is ALWAYS sending a 16:9 image (even if the left & right parts of the screen are black). The cable company is "center cutting" the image so you don't see the black on the sides and everything would show up like I described in the previous paragraph. Dish however is "letterboxing" the image. The letterbox puts black bars top & bottom (so you can see the full 16:9 image in a 4:3 screen). But since, during Seinfeld and other 4:3 programming, there's already black bars L&R, you now have black bars on all four sides. It would actually look SMALLER on a 16:9 set, because the image from dish is just filling the 4:3 "window" in the center.
Sounds like you may be right, but why would it be only one local that dish is not broadcasting like the rest? also is it a problem they can or will fix? It's not really that big a deal for me since seinfeld and the king of queens are the only shows I watch now. I watch them on 55 because they don't edit out as much of the show as TBS does for more commercial space, also none of those annoying bottom banner ads. Plus win football season gets here they have some games not available on other channels I get.
The problem is spatial scaling that occurred at the point of Dish receiving the local broadcast. They aren't receiving enough signal from the broadcaster and their decoder scaled the picture. That is how it was received and decoded, and that is what they send.
1 term
BS. Definitions of the terms you are using.
* Temporal (frame rate) scalability: the motion compensation dependencies are structured so that complete pictures (i.e. their associated packets) can be dropped from the bitstream. (Temporal scalability is already enabled by H.264/MPEG-4 AVC. SVC has only provided supplemental enhancement information to improve its usage.)
* Spatial (picture size) scalability: video is coded at multiple spatial resolutions. The data and decoded samples of lower resolutions can be used to predict data or samples of higher resolutions in order to reduce the bit rate to code the higher resolutions.
* SNR/Quality/Fidelity scalability: video is coded at a single spatial resolution but at different qualities. The data and decoded samples of lower qualities can be used to predict data or samples of higher qualities in order to reduce the bit rate to code the higher qualities.
* Combined scalability: a combination of the 3 scalability modalities described above.
These are not related to retransmission by satellite. They are related to the original source and what is done from:
* Streaming
* Conferencing
* Surveillance
* Broadcast
* Storage
E* takes these sources as given to them and just rebroadcast them after the satellite encoding process. If signal level is too low they loose the source and call the provider. The do not change these qualities. Signal level has little to do with any of these. It is either working, pixelating, or gone nothing else. How do I know these things I work for one of E*'s providers and if they loose the signal they call us almost instantly.
BS. Definitions of the terms you are using.
* Temporal (frame rate) scalability: the motion compensation dependencies are structured so that complete pictures (i.e. their associated packets) can be dropped from the bitstream. (Temporal scalability is already enabled by H.264/MPEG-4 AVC. SVC has only provided supplemental enhancement information to improve its usage.)
* Spatial (picture size) scalability: video is coded at multiple spatial resolutions. The data and decoded samples of lower resolutions can be used to predict data or samples of higher resolutions in order to reduce the bit rate to code the higher resolutions.
* SNR/Quality/Fidelity scalability: video is coded at a single spatial resolution but at different qualities. The data and decoded samples of lower qualities can be used to predict data or samples of higher qualities in order to reduce the bit rate to code the higher qualities.
* Combined scalability: a combination of the 3 scalability modalities described above.
These are not related to retransmission by satellite. They are related to the original source and what is done from:
* Streaming
* Conferencing
* Surveillance
* Broadcast
* Storage
E* takes these sources as given to them and just rebroadcast them after the satellite encoding process. If signal level is too low they loose the source and call the provider. The do not change these qualities. Signal level has little to do with any of these. It is either working, pixelating, or gone nothing else. How do I know these things I work for one of E*'s providers and if they loose the signal they call us almost instantly.
By inspiration...
How do I know these things? I have no degrees. I have no formal training. I have searched to know the truth of picture quality and the signal relationship since 2005. I am one of whom it is written:
1 Corinthians 1:27-29 KJVR But God hath chosen the foolish things of the world to confound the wise; and God hath chosen the weak things of the world to confound the things which are mighty; (28) And base things of the world, and things which are despised, hath God chosen, yea, and things which are not, to bring to nought things that are: (29) That no flesh should glory in his presence.
Jeremiah 33:3 KJVR Call unto me, and I will answer thee, and shew thee great and mighty things, which thou knowest not.
How do I know these things? I have no degrees. I have no formal training. I have searched to know the truth of picture quality and the signal relationship since 2005. I am one of whom it is written:
1 Corinthians 1:27-29 KJVR But God hath chosen the foolish things of the world to confound the wise; and God hath chosen the weak things of the world to confound the things which are mighty; (28) And base things of the world, and things which are despised, hath God chosen, yea, and things which are not, to bring to nought things that are: (29) That no flesh should glory in his presence.
Jeremiah 33:3 KJVR Call unto me, and I will answer thee, and shew thee great and mighty things, which thou knowest not.
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All right Jeff. I've been defending your position in at least two other threads. But I think you diagnosis is wrong on this particular problem, and the broadcast engineer (Sam Gordon?) is right. Some boob is incorrectly downconverting a 4:3 picture, either at the station or at Dish. When the culpable party notices his goof, he'll simply flip a switch somewhere and fix it. That is my prediction.
As for spatial scaling, I agree with you that it exists and it's visible, but it's not that visible! ("That" being to frame the entire picture in black.) What I believe this refers to is one type of error compensation where the video is reproduced at a lower resolution than it started out, because not enough data made it through intact to reconstruct the original picture in all it's pristine digital high-res perfection. It should still display at the same total size on your screen (not picture-framed!), resulting in a transient blurriness as the scalers inside the receiver do their interpolative magic.
jeff-
Want to actually TEST your theory instead of just trying to read white papers? Setup an OTA antenna, tuner, and TV. Tune in a local signal. Now, move the antenna AWAY from the transmit tower. Watch your signal level drop. Does the picture "SHRINK"?
I'm willing to bet as the signal level drops, first you'll see no change, then you'll see increased macroblocking/pixelization/freezes, then the "no signal".
Go ahead, try it. We'll wait.
Want to actually TEST your theory instead of just trying to read white papers? Setup an OTA antenna, tuner, and TV. Tune in a local signal. Now, move the antenna AWAY from the transmit tower. Watch your signal level drop. Does the picture "SHRINK"?
I'm willing to bet as the signal level drops, first you'll see no change, then you'll see increased macroblocking/pixelization/freezes, then the "no signal".
Go ahead, try it. We'll wait.
Ignore hideafjeff, he's constantly spitting out his propaganda that you don't have a good HD picture unless you have maxed out your dish. But this by far my favorite! It just so happened to drop signal on the side bars of the screen causing them to go black. LOL!!! AMAZING!! Maybe it's because the guy has a square LNB and not a rectangular 16:9 LNB right?
It would seem so.You guys are still entertaining deafjeff eh?
He appears to be on a crusade. And while I think some ire is warranted, error compensation in poor signal conditions is a good thing not a bad thing.Parable of the day: when all you have is a hammer, everything looks like a nail.
I already have witnessed it, and can recreate it.
A couple months ago, after a visit to my parents home, my Dad called me and asked why his picture was changing sizes since I left. I asked if it was when a commercial came on or went off. He said it was "anytime, during a commercial or during a program". I told him I'd have to come see. So I went and, lo and behold, the TV was doing it when I got there.
I was stumped on this one. When it shrank to postage size, using the format button would not change it. I did realize that I had left the auto format on, and so I turned auto format back off, and switched to a single format choice. The size of the picture then remained as it was set. I told my Dad that this was a new one on me, but I'd roll that one around for awhile and something would come to light.
What you don't know is that I live 30 miles from the transmitters and daily watch marginal OTA signal on a converter box. My parents also have low signal from their existing antenna, which I have left that way for research. (I get to see alot more aberrations that way, and they usually watch recorded stuff from the DVR.)
I had been searching since 2005 for the science behind digital picture quality variation in low signal environments when I found that the answer for both picture quality and size change was contained in MPEG SVC extension. Scalable video coding. (Previously known as Signal-to-noise Ratio (SNR) Scaling.
The name of the article is:
"Overview of the Scalable Video Coding Extension of the H.264/AVC Standard"
(Let me just add here that the previous name of SVC scalability was SNR scalability. That's Signal-to-Noise Ratio Scalability.)
The abstract states it very simply:
Abstract—With the introduction of the H.264/AVC video coding standard, significant improvements have recently been demonstrated in video compression capability. The Joint Video Team of the ITU-T VCEG and the ISO/IEC MPEG has now also standardized a Scalable Video Coding (SVC) extension of the H.264/AVC standard. SVC enables the transmission and decoding of partial bit streams to provide video services with lower temporal or spatial resolutions or reduced fidelity while retaining a reconstruction quality that is high relative to the rate of the partial bit streams. Hence, SVC provides functionalities such as graceful degradation in lossy transmission environments as well as bit rate, format, and power adaptation.
And,
Moreover, the basic tools for providing temporal, spatial, and quality scalability are described in detail and experimentally analyzed regarding their efficiency and complexity.
Index Terms—H.264/AVC, MPEG-4, Scalable Video Coding (SVC), standards, video.
Read it for yourself! Very interesting! http://ip.hhi.de/imagecom_G1/assets/pdfs/Overview_SVC_IEEE07.pdf
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When you describe full screen with blurriness, that is an example of fidelity/quality scaling. When I describe the "postage stamp' screen (Full quality/fidelity, smaller size) that is an example of spatial scaling (less space but proper resolution). There is also temporal scaling but I'm not going to get into it here.
When all is said and done, either of us could be right. Whether it was a flip of a switch or the effects of scaling at the provider, I don't expect anyone to get an answer to this one.
Thank you again for speaking up. A person either has to have seen it (PQ variances) on their television or they have to be searching for the quality they've seen elsewhere to know that digital picture quality varies. Experience in correcting these issues, and digital science, both attest to the signal/PQ relationship.
I still think the guy's LNB that he got installed was a 4:3 LNB and not a 16:9 LNB.
Just like back in the day you had to make sure you bought a color TV antenna and not a black&white one...also like you have to buy a HDTV antenna to pick up digital signals.
Just like back in the day you had to make sure you bought a color TV antenna and not a black&white one...also like you have to buy a HDTV antenna to pick up digital signals.
