About JEB11

@Rustyben wrote: that's not how it works. The signal from the satellite eventually will be a master version at 4k or later 8k progressive format that is received by a 'recoder' that provides 8k/4k/HDR/etc and HD 720p60 and SD versions all from the single copy sent via the satellite that uses the next generation HEVC security. The recoder puts out the signals in the Mpeg4 or Mpeg2 format for each streamed output.  As an example, you get TV land normally in SD. but go to TVland TVgo and it is in HD. All the same satellite feed just recoded. That is why the conversion to all progressive format is being made for satellite delivered signals. I don't have quite the technical sophistication to follow all of this.  Is the punchline that the conversion of all channels to 720p is more of an interim step to delivery of higher resolutions via satellite feed and it's nothing to be concerned about at this point?  If so, you have answered my question. ... View more

@jkozlow3 wrote: @JEB11 wrote: Ok.  I think I'm beginning to understand where you are coming from.  Let me ask one more follow-up question.  Would you be satisfied with a 720p signal if it were possible to persuade Comcast to cut out (or at least cut back) the post-conversion shenanigans, like overcompressing and bit-starving the transmission signal?  I ask not because I'm trying to paint you into a corner, but because I'm trying to isolate what's really causing irreparable damage to the image.  That is where we should be focusing our efforts to get Comcast to do something.  Is it the conversion to 720p itself or the post-conversion processing creating the mischief?   I read somewhere about a petition demanding that Comcast return to the status quo and restore the 1080i signal.  But before I pick up a pitchfork and join the villagers in the town square for the corporate officer weenie roast, I'd really like to know if that alone would make much of a positive difference, on balance.  I personally believe that professional deinterlacing is very beneficial because many (maybe most) of us can't perform that function very well with our consumer-grade equipment.  And, there are only two ways that Comcast can do the deinterlacing for us starting from a 1080i base signal: go up to 1080p or down to 720p.  1080p isn't going to happen.  Comcast won't do it because it requires too much bandwidth.  It strikes me that 720p would actually be a very good alternative if upscaling isn't nearly as problematic for us as deinterlacing.  With a conversion to 720p, you'd get professional equipment applied to the deinterlacing function, leaving consumers with only the relatively easy task of upscaling to 1080p (or higher) using consumer-grade equipment generally adequate to the task.  If this is correct, then the fight really ought to be targeting the post-conversion processing (compression and bit rate reductions), not demanding that Comcast restore the 1080i signal.  Unless I'm misreading the tea leaves, it sounds like we could work effectively with a 720p signal, so long as Comcast otherwise leaves it alone.  I think you agree with me on that, unless I've misunderstood.  See Message 113 ("The critical issue... is less the 720p part.  720p can look good, and upscale well - IF the source encoding is very good.  Comcast is overcompressing the signal during the MPEG4 conversion, and reducing the bitrates on the program to just barely good enough.)"    At this point, we're simply speculating, are we not?  We don't know 100% WHY the picture quality is worse, we just know it is.   Yes, perhaps 720p would look fine if they didn't overcompress it.  But I don't know that we're benefiting as much from "professional deinterlacing" as you think.  Maybe we are, maybe we're not.  I'd personally like to see side-by-side comparisons.  I've always output 1080p from my X1 box, allowing the X1 box to do the deinterlacing.  When I set the X1 to output 1080i (allowing my TV to do the deinterlacing instead), I couldn't really tell a difference.  I personally think both devices handled the deinterlacing well enough.   Yes, deinterlacing has been an issue in the past (it was a BIG issue many years ago with consumer grade equipment such as when HDTVs were first becoming mainstream), but I'm not sure that it's still a big issue for most material.  I suspect that most consumer grade equipment deinterlaces good enough these days.  I remember testing 2 blu-ray players side-by-side many years ago (8+) with SD DVDs (480i).  I found a movie (American Beauty) that had some serious issues when allowing the blu-ray player to deinterlace the signal (it didn't matter if I output 480p or 1080p - the conversion from interlaced to progressive was the issue).  There were several scenes that had a lot of artifacts.  I borrowed another copy of this movie from a friend and hooked up 2 different brands of blu-ray players side-by-side into 2 different inputs on my AVR so that I could quickly switch back and forth.  The difference was astounding and 1 player handled the deinterlacing without any visible issues.   So, back to Comcast.  I don't know exactly what the issue is.  All I know is that the picture quality is noticeably worse now than it used to be.  Could 720p suffice if they didn't overcompress it?  Perhaps.  I'm not demanding 1080i, but I *would* like a better picture - however they achieve it.  I wish Comcast would have tested on larger TVs (65" and larger) and taken picture quality into account before choosing to do whatever they've done.  It looks bad. I couldn't agree with you more.  We are indeed speculating, and that is precisely what I take issue with.  I was hoping that someone with far more expertise in the AV sciences than I could chime in and identify the culprit.  Is it the conversion to 720p that's causing the problem?  The post-conversion encoding?  Both?  I certainly don't know, so I asked the question.  But the "I-don't-like-it-change-it back" approach for me is neither productive nor compelling because it doesn't advance the ball in any systematic way.  If Comcast granted the wish and went back to 1080i but continued to apply the same encoding scheme to the 1080i signal as it currently does to the 720p signal, would we be better off?  Shoudn't we know before stomping our feet and demanding that Comcast do it?  It strikes me as a wasted effort if we get what we ask for, and the picture still stinks because we didn't ask for the right thing. ... View more

@charissamz wrote: Following this closely. Maybe we will see PQ improvemnts if you use an app as a cable box. If so, I would love to see this app on AppleTV or even a cable box that runs the app. I guess that would be IPTV, correct?   http://www.avsforum.com/xfinity-tv-beta-app-comes-roku-live-tv-demand-dvr/ Very hard to say.  The conversion to new and different hardware and platforms is still in its infancy.  To the extent that devices like the Roku function as set top box alternatives, and nothing more, then I think in the short term, the damage to the image that is occurring at the post-conversion encoding stage would probably just flow through the new hardware leaving you more or less in the same place as far as picture quality goes.  But, if the long-term plan is eventually to convert everything over to an internet-based TV system and no longer support a duplicative traditional cable delivery system running in parallel, I could see that as freeing up a lot of bandwidth that could be put to better use than transmitting the same channels twice.  Improved picture quality may very well be one of those uses. ... View more

@webminster wrote: So first I'm no expert on the subject, only an A/V amateur who watches way too much video.  And bought some good mid-scale (not "professional grade") equipment because of that.  And, needs a decent quality signal to make the investment worth it...   That said, part of the deal is is subjective.  Comcast eludes to that in their releases that they had feedback from many focus groups to arrive at their strategy.   I'm sensitive to video issues, dithering, macroblocking, pixelation, what-not.  My wife, on the other hand, not so much... I see something and say "what was that?"... she says, "what?".   So much of what Comcast has done revolves around the majority of customers who can't, for whatever reason, see the difference.   Speaking from my view only, the amount of discomfort, if any, in the past from deinterlacing artifacts on the various monitors and STBs I've used is minor compared to the post-migration changes.   Right after the migration, I could see the loss of detail, and the dithering.  call that what you will, but from my (subjective) perspective, the "cure" for any perceived deinterlacing issues is far worse.   Many people on other threads (like at DSLReports) also feel the same, FWIW.   One positive - before the migration, a lot of channels were encoded my Comcast with a switching interlaced/progressive format (the signal rapidly changed back and forth).  In Windows Media Center circles, we referred to the syndrome as "29/59" and it could drive a video card nuts (only some video cards did a decent job coping with it).  Even then, sometimes you could see some "shimmering" on channel ID bugs.  Since the migration, those channels are now stable since they're re-encoded as pregressive, no switching.  But it's a 1-forward-1-back situation - the bugs are stable, but the picture is softer and you can see dithering on some channels on occasion.  My choice?  Hard, but I'd take the former.   I suspect all the deal with progressive and deinterlacing still matters more for the streaming end.   Is Comcast trying to unify their signal so they don't have a mobile-optimized and a home-TV-optimized delivery, just one?  Since deinterlacing on phones and tablets is much worse that consumer-TV equipment, perhaps.   Comcast keeps me out of the loop on their strategic plans. Ok.  I think I'm beginning to understand where you are coming from.  Let me ask one more follow-up question.  Would you be satisfied with a 720p signal if it were possible to persuade Comcast to cut out (or at least cut back) the post-conversion shenanigans, like overcompressing and bit-starving the transmission signal?  I ask not because I'm trying to paint you into a corner, but because I'm trying to isolate what's really causing irreparable damage to the image.  That is where we should be focusing our efforts to get Comcast to do something.  Is it the conversion to 720p itself or the post-conversion processing creating the mischief?   I read somewhere about a petition demanding that Comcast return to the status quo and restore the 1080i signal.  But before I pick up a pitchfork and join the villagers in the town square for the corporate officer weenie roast, I'd really like to know if that alone would make much of a positive difference, on balance.  I personally believe that professional deinterlacing is very beneficial because many (maybe most) of us can't perform that function very well with our consumer-grade equipment.  And, there are only two ways that Comcast can do the deinterlacing for us starting from a 1080i base signal: go up to 1080p or down to 720p.  1080p isn't going to happen.  Comcast won't do it because it requires too much bandwidth.  It strikes me that 720p would actually be a very good alternative if upscaling isn't nearly as problematic for us as deinterlacing.  With a conversion to 720p, you'd get professional equipment applied to the deinterlacing function, leaving consumers with only the relatively easy task of upscaling to 1080p (or higher) using consumer-grade equipment generally adequate to the task.  If this is correct, then the fight really ought to be targeting the post-conversion processing (compression and bit rate reductions), not demanding that Comcast restore the 1080i signal.  Unless I'm misreading the tea leaves, it sounds like we could work effectively with a 720p signal, so long as Comcast otherwise leaves it alone.  I think you agree with me on that, unless I've misunderstood.  See Message 113 ("The critical issue... is less the 720p part.  720p can look good, and upscale well - IF the source encoding is very good.  Comcast is overcompressing the signal during the MPEG4 conversion, and reducing the bitrates on the program to just barely good enough.)"  ... View more

@webminster wrote: There's no end of arguments from Comcast and supporters that we're better off.  Personally, with my 65" OLED set and decent equipment, I disagree, since I can see it.   I'd say your premise could be true (the "professional-quality deinterlacing"), if we knew that to be the case.  The only best way here is 720p from the source, not Comcast re-encoding the signal.   Still stand behind the last premise though... As long as Comcast is going to drain all the bitrate out of the signal, overcompress it, the game ended before it started.  No amount of upscaling or other CP-end signal processing can restore the lost detail. Your answer is a little unclear, so let me take another stab at formulating a better question.  I actually offered two foundational premises, both of which I would like you to assume as correct for pedagogical purposes:  Premise (1) from the article I cited ("Since consumer electronics equipment is typically far cheaper, has considerably less processing power and uses simpler algorithms compared to professional deinterlacing equipment, the quality of deinterlacing may vary broadly and typical results are often poor even on high-end equipment."); and Premise (2) that Comcast is in fact using professional grade equipment that most consumers do not have access to and is using it correctly to perform competent deinterlacing.  I fully recognize that Premise (1) does not apply to you personally, because you have professional-grade deinterlacing equipment; and Premise (2) is very difficult to accept, and with good reason.  But I'd like you to accept both premises anyway for the sake of argument.   Are you saying that, for most consumers, and starting with the typical broadcast 1080i source signal, the positive benefits of a professional-quality job of deinterlacing are fully negated by the negative effects of downscaling to 720p, bitstarving and overcompression to produce on balance an inferior signal quality?  Again, I emphasize most consumers, not you personally.  I know you have excellent equipment and I accept your counter premise that you don't need Comcast's help with deinterlacing.   I'm not angling for a particular answer here.  I'm just trying to figure out what matters more.  I was under the impression that bad deinterlacing is deadly (and very common, given the quality of even some high-grade consumer equipment) because it can produce all kinds of really bad things, like dropped frames and artifacts.  So, if you can't have everything (and, practically speaking, you can't) and you had to pick one thing to do really well, deinterlacing is a pretty good place to start because it's so hard for most consumers to do correctly.  If that impression is wrong, I'd like to know that.     ... View more

@webminster wrote: People can argue the veracity of 720p vs 1080i.  But there's points that have to be kept in mind:   * 1080i can have deinterlace problems.  But a decent contemporary deinterlacer can do a good job.  However, mobile devices don't tend to have good capability here, so the progressive format works better if you want to play on mobile devices, or try to least-common-denominator your streams to work on both mobile and TV devices.   * 1080p would be holy grail.   However the bandwidth requirements for cable companies to do 1080p given current plants is not practical (without implementing SDV, or dumping traditional TV delivery for something like IPTV).   * 720p does, or course, drop about 55% of the pixels compared to 1080(i/p).  If you have a native 1080 or 2160 (4k) display, of course those pixels have to be interpolated (synthesized).  Stipulation, if you have a display and STB that uses directly the 720 signal... but the pixel mapping still has to happen.   * The critical issue... is less the 720p part.  720p can look good, and upscale well - IF the source encoding is very good.  Comcast is overcompressing the signal during the MPEG4 conversion, and reducing the bitrates on the program to just barely good enough.  MPEG4 compression works based on a quality/compression ratio - the more quality you can sacrifice (e.g. fine detail), the more bandwidth you can save.   Comcast has compressed the signal to death to cram more channels together in a QAM.   The loss of fine detail, and in many cases the dithering you can see during scene transitions, I believe are rooted in this.   That last part was not publicized as part of the MPEG4 migration (actually, few details were).  But it's the part that causes customer dissatisfaction.   Other systems (like DTV) do MPEG4 as well - but they don't bitrate-starve the result so badly, and the picture looks better. This is really interesting.  Maybe you can answer one additional question.  I read that consumer electronics frequently don't deinterlace well and that even the high-end stuff produces inconsistent results. https://en.m.wikipedia.org/wiki/Deinterlacing.  If that is true, and I don't know for sure that it is (I recognize my source is dubious), is a 720p signal as Comcast now distributes it on balance "better" than the 1080i signal that used to be Comcast's dominant format?  You gain professional deinterlacing at the distribution source--a difficult and not always successful process for consumer electronics--but you pay a penalty in the form of reduced pixels and overcompression after deinterlacing has been performed and just prior to distribution.  Are we better or worse off with these changes? ... View more

@jkozlow3 wrote: Yeah, I hear you. It's my understanding that SCALING is easy but DE-INTERLACING is difficult to do well. So I'm not sure there'd be much of a difference in 720p vs. 1080p. But who knows. Good point. But it does confirm that my original output resolution--1080i--is likely to be the worst possible alternative most of the time, now that Comcast will deliver very few channels in that format.  ... View more

@jkozlow3 wrote: 720p may be correct for most channels, but some of the local channels still broadcast in 1080i. So outputting 720p would be downscaling in some instances. Since the X1 box doesn't support native resolution, I output 1080p from the X1 since my TV would have to convert it to 1080p anyway. You might want to at least consider switching to 720p.  With few exceptions, like maybe the Vizio I referenced above, an STB will do a considerably poorer job of upcaling 720p to 1080p than the video display's internal processor would.  The video processors in STBs are notorious for their low bidder-driven poor quality.  I haven't heard anything to the contrary about the video processors in the Arris and Pace X1 boxes. That's precisely why the native function was so popular with videophiles--the box would only descramble the signal and then pass it on unprocessed.    You're right about the penalty of letting the STB de-scale and de-interlace to 720p those channels still received natively in 1080i.  But it sounds like Comcast's recent change to the signal quality of the vast majority of its channels makes that a concern only for a few local broadcasts.  And even some of those local affiliates (ABC and Fox, for example) already broadcast natively in 720p, making 1080i to 720p conversions even more rare.  But, no question.  It'll be bad when it does occur.  I'm just trying to figure out which setting will cause the fewest problems since none will eliminate them. ... View more

X1 DVRs have no native setting--for me, one of the biggest drawbacks to parting with my DCX3400.  I have no confidence in the video processors built into STBs (the X1 included) and I have no desire to change resolution manually depending on the source.  So, to get as close to "native" as possible for the most channels, I previously set my X1 box to output 1080i.  To maintain the highest level of "nativeness" for the most channels, it sounds like the proper setting for X1 boxes is 720p, now that Comcast has converted all but local broadcasts to 720p.  Is that right?   This change to the source signal is more than a small pain in the posterior.  I was about to pull the trigger on a Vizio P75-C1, now that prices have dropped below $3K.  But the scalers on the Vizio do a relatively poor job on input sources at or below 720p.  Perfect!  That's Comcast's new and "improved" source resolution.  So, I would have no choice but to use an external video processor if I went with this TV and stayed with Comcast.  No way would I plug directly into the TV and rely on the STB to upconvert.  Ugh. ... View more