AVS Forum banner

Status
Not open for further replies.
1 - 20 of 36 Posts

·
Registered
Joined
·
541 Posts
Discussion Starter · #1 ·
I have recently removed WETA-DT from my channel list. I can't believe how much their picture quality has deteriorated since they began multicasting. I am of course speaking of channel 27.1 that's on the air from 8 pm to midnight, their so-called HD Showcase channel. I contacted their Web site to express my disappointment. Not only that, but their audio is terribly out of synch. To boot, they do not pass along any of PBS current HD offerings, some of which go out in DD 5.1.

I would be interested in hearing from other viewers and what their thoughts are.
 

·
Registered
Joined
·
302 Posts
I agree that the quality of WETA-HD's recent broadcasts has declined. I was watching Chiluly over Venice the other night and was quite disappointed. At times the clarity of Chiluly's facial outline was reduced to the point where I was distracted from what he was saying. I have seen the Chiluly over Venice program several times earlier this year and thought that the HD quality at the time was excellent. WETA-HD used to have the very best quality of any HD programming. If multicasting is the problem, I do wish that they would re-evaluate the wisdom of pursuing this form of broadcasting.
 

·
Registered
Joined
·
1,270 Posts
WETA is an interesting example of multi-casting. When they were just sending out two channels (WETA HD and WETA 26 SD) the picture quality of WETA HD suffered from macro blocks due to bit starvation of the HD feed. While some of the specials do look fantastic, I never considered them the best example of HD. The multi-casting of WETA SD caused too many compression artifacts, but they have certainly been a strong supported of HD and DTV.


Now with four channels being multi-cast the situation MAY BE worse. It's strange that this is the case. Here's why.


During prime time the 3rd and 4th sub-channels are being broadcast but the data rate of the those channels should be in the kilobits ranges since they are just static images. This should have little to no effect on the HD and SD channels. Essentially, we should be seeing pretty much the same quality HD that we've always seen from WETA. However, if they have something mis-configured there may be too many bits being sent out for the 3rd and 4th sub-channels during prime time. That would certainly degrade the HD picture.


If anyone has measured the WETA average bit rates it would be interesting to know if there is a difference since the change to 4 channels. My guess is that they have something set wrong in the MPEG encoder and the 3rd and 4th sub channels are using bits that they don't need.
 

·
Registered
Joined
·
302 Posts
I hope that the problem is something as simple as an MPEG encoder setting. I did notice that the infomercial just before Chiluly looked excellent. That was the segment where WETA's spokesman is talking about the benefits of multicasting in the classroom and elsewhere. The spokesman's facial outline and all the objects around him were crystal clear. If the problem is with an MPEG encoder setting, it must occur only during the main programming and not during the segments in between.
 

·
Registered
Joined
·
284 Posts
I actually like the multicasting during the non-prime hours. On several occasions I've found some alternative programming there that I really enjoyed.


However, I wish they'd just do away with their HD Showcase and broadcast the regular PBS HD programming, instead of showing it only in SD. We've yet to see "Rudy Maxa's Travels in Europe" that everyone raves about; and I think that all of the new NOVA episodes are in HD. Of course, they also need to quit multicasting one SD channel with the HD channel. Those MPEG motion artifacts have become intolerable.


It seems to do no good to write to them, by the way. They never respond to comments or questions (at least, not in my experience -- and I've tried several times).
 

·
Registered
Joined
·
37 Posts
I agree as well - the picture quality of the true-HD material broadcast nightly (8pm-11pm) on 27-1 is horrid!


As much as they were monotonous, the endless showings of Japan Garden, Lincoln, Virginia Reel etc were far superior in image quality compared to what we currently see in the new 'showcase' format. At least they were good demo material for visitors who have never seen HD. WETA is currently not worthy of demo-ing to HD newcomers.


It's somewhat amazing that other PBS stations throughout the country have far better HD broadcasts (even actual first-run simulcasts!) than WETA.


The whole concept of 'multicasting' is corrupting the true value of HD - increased image quality.
 

·
Registered
Joined
·
33 Posts
I'm upset that they turn off the simulcast of their regular programming at 8:00 pm. I used to enjoy the better reception of their prime time programming on the digital channel. My e-mails and letters to the station went unanswered. Guess who's not getting any more donations from me!
 

·
Registered
Joined
·
40 Posts
I have to echo Steve's comments - it seems like they made a serious error in showing HD Showcase and WETA Prime during primetime - this means that they have no digital channel showing their "real" broadcast! They should be showing 1 HD channel and 1 SD channel simulcasting their analog station.

I've also e-mailed fairly regularly about this and the awful bit rate problem, but got no response - this is disappointing. I'm a former WETA employee, and always found that the programming and tech staff were very responsive to viewers. And in the past when WETA was beginning their digital experimental phase, VP Terry Bryant and Marilyn Pierce were always available to talk about DTV. (I live down the street from WETA, and my living room was sometimes a test site, which was fun!) Now, they're both gone.

I'm afraid that there has been a changing of the guard in several departments at WETA and they seem to be focusing less on being accessible to viewers and more on revenues. Not without reason, I'm sure, but still disappointing.
 

·
Registered
Joined
·
1,132 Posts
If a local PBS station does not make itself accessible to the public, then, of course their revenues will go down. We are lucky in this area of Michigan of having a fine PBS station..located at MSU, East Lansing, Mi.
 

·
Registered
Joined
·
37 Posts
My impressions of WETA:


WETA used to be almost a flagship PBS station, probably one of the better PBS stations in the country due to it's location (in the DC area) and it's sponsorship of many productions that are/were syndicated nationally on other PBS stations.


With this in mind, the manner in which WETA has conducted it's operation of the HD channel is somewhat quizzical. You would think that WETA's HD transmissions would be world-class, again, amongst the best PBS digital stations.


Gene's insight as a former WETA employee is interesting. I suppose it does all go back to funding and management. If the funding is not there, and even if it was, if the management is not pro-HD what is to be expected?


It's just a shame that in the FCC's back yard, what should be (and has been?) a flagship PBS station has such a dismal showing in it's HDTV transmission.


tj
 

·
Registered
Joined
·
2,765 Posts
Quote:
Gene's insight as a former WETA employee is interesting. I suppose it does all go back to funding and management. If the funding is not there, and even if it was, if the management is not pro-HD what is to be expected?
I think this is on point. In the past I remember seeing some info on digital in the back of the monthly flyer. Lately there hasn't been anything at all on HD or digital. Seems like bad timing on WETA's part - be a pioneer then drop the ball when all the HDTVs start flying out of the stores. Personally I will tune to Annapolis (much further) for the better signal strength if there was a program I wanted and it was on both.
 

·
Registered
Joined
·
1,288 Posts
Quote:
Originally posted by JoeFloyd
During prime time the 3rd and 4th sub-channels are being broadcast but the data rate of the those channels should be in the kilobits ranges since they are just static images. This should have little to no effect on the HD and SD channels.
Well, here are the actual numbers:


27-1: 12.80 Mbps

27-2: 3.60 Mbps

27-3: 1.00 Mbps

27-4: 1.00 Mbps


Although -3 and -4 seem high, with forced I-frames every so often, it's tough to get MPEG-2 at 640x480 down much lower, even on static material.


I think one real issue is that they have another 1Mbps or so they could dedicate to the HD channel.
 

·
Registered
Joined
·
1,270 Posts
nabsltd,


Thanks for the bit rate info. That pretty much indicates that 26.3 and 26.4 are using 2 Mbits that were available to the 26.1 HD before the transition.


There is a tool from Moonlight (same company that makes the Elecard MPEG decoder) called MPEG Stream Explorer which can show the sequence of IPB frames. Using 1 Mbit/s seems a little too high to me. Just based on my visual observation, I think the forced I frame is about once a second. I tend to think that 1 Mbit/s may be the minimum allowable bit rate for their encoder, but it's certainly possible to encode a low res static image with fewer bits.

http://moonlight.co.il/products/StreamExplorer.shtml


In order to use this tool you may need to convert a transport stream capture into a standard MPEG stream using the HDTVToMEPG2 utility.
 

·
Registered
Joined
·
979 Posts
Another observation: My Dish 6000 will not even display 27.3, 27.4 when 27.1 is in HD mode. The receiver indicates signal present (meter), but only black screen. I realize the 6000 isn't to be considered a reference receiver, but it may indicate that even at 1 Mbps, they are operating on the fringe of spec. Why not just shut-off 27.3 & .4 in the evening?


Gerald C
 

·
Registered
Joined
·
1,288 Posts
Quote:
Originally posted by JoeFloyd
There is a tool from Moonlight (same company that makes the Elecard MPEG decoder) called MPEG Stream Explorer which can show the sequence of IPB frames. Using 1 Mbit/s seems a little too high to me. Just based on my visual observation, I think the forced I frame is about once a second.
Although I think 1Mbps is too high as well, I seem to recall that the ATSC spec requires more frequent I-frames to help keep down the length of glitches due to reception problems.
 

·
Registered
Joined
·
302 Posts
Quote:
Originally posted by nabsltd
Well, here are the actual numbers:


27-1: 12.80 Mbps

27-2: 3.60 Mbps

27-3: 1.00 Mbps

27-4: 1.00 Mbps


...I think one real issue is that they have another 1Mbps or so they could dedicate to the HD channel.


So, multicasting appears to be a problem for high quality reception on 27-1.

How disappointing for Washington area viewers. Does Baltimore's WMPT do multicasting? I seem to remember reading that WMPT simply passes the national PBS HD signal. If so our friends to the north are very fortunate indeed.
 

·
Registered
Joined
·
302 Posts
Quote:
Originally posted by nabsltd
Well, here are the actual numbers:


27-1: 12.80 Mbps

27-2: 3.60 Mbps

27-3: 1.00 Mbps

27-4: 1.00 Mbps


...I think one real issue is that they have another 1Mbps or so they could dedicate to the HD channel.


Seeing those numbers makes me far less enthusiastic on the idea of multicasting. Does Baltimore's WMPT on Comcast do multicasting? I seem to remember reading that WMPT simply passes the national PBS HD signal. If so our friends to the north are very fortunate indeed.
 

·
Premium Member
Joined
·
1,572 Posts
> "If so our friends to the north are very fortunate indeed."


WMPT is currently broadcasting only from Annapolis. So for folks in the DC area, it is "our friends to the east." From reports here, the signal is so strong that reception is good even at points far west of DC.


WMPT's Owings Mills location (north east of Baltimore) is supposed to be on-line in the spring.
 

·
Registered
Joined
·
342 Posts
Some info which I recently (12/16) received from WMPT -


They are at full power now. Explains why reception is so good well outside of Annapolis. AT 40 miles from me, WMPT is my cleanest signal, not quite strongest, but certainly cleanest.


As for multicasting , it is there plan to begin in February.
 
1 - 20 of 36 Posts
Status
Not open for further replies.
Top