That's simply a function of the capacity of a TV channel. The data rate cannot exceed about 18.3Mbps for all the program streams multiplexed together and that's not really enough for a single full-range 3840x2160 UHD stream (especially if real-time compression is being applied). I recall that one of the services that streams advanced UHD recommends a consistent 25Mbps down speed to insure smooth play.
4K TV broadcasts are coming
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I think I partially misinterpreted what you were trying to communicate in my previous reply so I'll take another run at it:
The various broadcast standards (NTSC, DTV, ATSC 3.0) are necessarily incompatible. DTV and ATSC 3.0 both involve multiplexing multiple program streams together in a single bitstream and of course NTSC sent only one uncompressed AM video stream along side an FM audio stream.
So your recollection that UHD had anything to do with compatibility is absolutely false. The incompatibility comes from the fact that the different broadcast standards simply aren't compatible. The UHD HDR/WCG issue is entirely that of not having enough brandwidth available in a TV channel.
If that's the case I hope we see some UHD-BD releases of season sets of these shows with HDR as well.
I want arguing that UHD by itself won't fit in a 6 mhz TV channel bandwidth MPEG-H HEVC / H.265 will assure that only that I thought I read current HDTV TV transmitters can not transmit Mpeg 2 or H.264/MPEG-4 AVC ATSC 2.0 720p/1080i / 480i and ATSC 3.0 up to 2160p HDR HLG MPEG-H HEVC / H.265 all on the same RF transmitters .
What about the spectrum will ATSC 3.0 need its own radio radio spectrum alongside ATSC 2.0 for a time that they may co exist or will HDTV and 480i SD Digital TV fit in the ATSC 3.0 radio spectrum alongside UHD TV all with MPEG-H HEVC / H.265 but that will need ne RF tuners either way .
I'm no expert and I'm not making the arguments beyond what I think I read .
Wording it another way my question is will ATSC 3.0 up to 4K HDR HLG MPEG-H HEVC / H.265 and 480i to 1080i HDTV fit in the the same physical layer and TV transmitter as the core HDTV transmission system today ?
No commercial station is transmitting ATSC 2.0. Transmissions are ATSC 1.0.
From ATSC.org:
"By way of background, the ATSC 2.0 effort was undertaken by TG1 as a result of direction from the ATSC board of directors in 2010 to:
“…develop comprehensive standards for the next generation of fixed-broadcast digital television (DTV) services…[which] shall be carried in DTV broadcast channels and the presence of these services shall not preclude or interfere with proper operation of current ATSC services in the same RF channel or have any adverse impact on legacy receiving equipment.”
Simply put, ATSC 2.0 is a new set of backwards-compatible tools and features that can be carried over the ATSC 1.0 RF layer and MPEG-TS Transport Stream without negatively impacting fielded receivers. TG1 embarked on new work that included a number of new features and technology ultimately codified in the A/107 ATSC standard and its subordinate specifications."
From ATSC.org:
"By way of background, the ATSC 2.0 effort was undertaken by TG1 as a result of direction from the ATSC board of directors in 2010 to:
“…develop comprehensive standards for the next generation of fixed-broadcast digital television (DTV) services…[which] shall be carried in DTV broadcast channels and the presence of these services shall not preclude or interfere with proper operation of current ATSC services in the same RF channel or have any adverse impact on legacy receiving equipment.”
Simply put, ATSC 2.0 is a new set of backwards-compatible tools and features that can be carried over the ATSC 1.0 RF layer and MPEG-TS Transport Stream without negatively impacting fielded receivers. TG1 embarked on new work that included a number of new features and technology ultimately codified in the A/107 ATSC standard and its subordinate specifications."
Your questions are hard to answer because they impose impossible conditions but I'll repeat my answers because I think I have you figured out:
Repeat after me: You cannot mix NTSC, DTV or ATSC 3.0 (or any other modulation scheme so conceived and so dedicated) on the same RF TV channel.
By definition, each modulation scheme consumes an entire TV channel. That said, the transmitter is simply relaying bits; is doesn't care which modulation method is used (as long as it is understood that, like in the Highlander movies, "there can be only one").
You can't fit full 3840x2160 with HDR and WCG in with anything else in 18.3Mbps and hope to reap the benefits. I'm of a mind that h.265 will never get to the point where it can encode 3840x2160p with HDR and WCG in real time to fit in a TV channel. You CAN send streams in different resolutions if you're willing to give up quality but then any benefits of UHD will almost certainly be lost. Again, by definition, these streams must all employ h.265 compression.
This is much the same way as it is today with 1080i and 1080p. Blu-ray and other formats employing MPEG4 or better can deliver full 1080p HD but DTV broadcast is limited to 1080i because it is limited to using MPEG2 and only provides the aforementioned 18.3Mbps of bandwidth. The ATSC decreed that 1080p would not be supported with DTV because of this.
The relevant "proposed standard" (one of those elements of ATSC 3.0 that doesn't appear to be cast in stone yet) is A/341. If you want to know what's really going on, read the linked document. It speaks to what will and will not be supported and I have to admit that I'm very disappointed that it isn't slated to support HD with HDR or WCG. I think we could all be pretty happy most of the time with HD that came with these additions; especially if it fit in the bandwidth along with other things we want.
"Your questions are hard to answer because they impose impossible conditions but I'll repeat my answers because I think I have you figured out:
Repeat after me: You cannot mix NTSC, DTV or ATSC 3.0 (or any other modulation scheme so conceived and so dedicated) on the same RF TV channel.
"By definition, each modulation scheme consumes an entire TV channel."
Re:
I thought that your entire reply was wholly obvious
From your official link noting I was never referring to synthesize HDR content my TV can do all that ,
ATSC S34-168r8 Video – HEVC 17 January 2017
13
6.3.2.3 HLG transfer characteristics
For HDR video with the HLG transfer characteristics, the following constraints apply
I asked about more spectrum vis a vis another RF transmitter and RF spectrum or not since you maybe disputed that one transmitter can not do that If I understood correctly prior to reading just above here for simultaneous 480i/HDTV and ATSC 3.0 2160p up to HDR HLG that obviously combined may not fit in a single regulated HDTV channel HEVC notwithstanding at any decent quality below the lower nyquist rate .
Some background you may have a misunderstanding here you may not know beyond what I can read on the web about HLG HDR and ATSC 3.0 anyway as for the other maybe thats debatable this is not my career and I'm not familiar with you .
I understand at an enthusiast level with an electronics education in the late 1960's to 1970 and practical knowledge ,brief TV bench work and some self study going forward PC's starting in early 1980's can build and fix same , some electronics at the board level ,ohm's law ,radio RF propagation and amatuer radio at in part maybe nearly FCC gen class but dated, enthusiast level and my education Digital discrete time signals and IPTV , mpeg compression and audio codecs ,HEVC and so on , electrical conductivity LCD panels ,nyquist rates lower nyquist rates , digital signal sampling ,perceptual lossy encoding , lossless encoding,noise shaping Dolby AC-4 and MPEG-H 3D Audio MPEG-2 / H.262 and MPEG-4 AVC / H.264 video codecs. MPEG-H HEVC / H.265 codec RF modulation and so on.
Not everything about any of this and not any of it at a career level but I can bench TVs ,PC , and some radios and so on ,
From another post of mine here something maybe speculative and factual in case you missed it , it's unofficial ,
AFAIK Hybrid Log-Gamma (HLG) is the ATSC 3.0 proposal under consideration maybe you know something my web links don't or no ? .
** HLG is supported by HDMI 2.0b, HEVC, and VP9 Freeview Play and YouTube.
HLG does not need to use metadata since it is compatible with both SDR displays and HDR displays. HLG can be used with displays of different brightness in a wide range of viewing environments.
** source -Wikipedia -
February 3, 2017 FCC Pushing for ATSC 3.0 Standard for Over-the-Air 4K Broadcasting With HDR
Some of the new broadcast content enhancements that would come with ATSC 3.0 implementation include the already-mentioned capacity for 4K resolution along with HDR (using new broadcast-friendly standards like Hybrid Log Gamma), higher frame rates for content, wide color gamut and even direct-to-mobile device broadcasts of next-generation over-the-air content.
All of these ATSC 3.0 enhancements are still a ways off and while the mainstream 4K TVs of 2017 that are now being released in the U.S don’t have ATSC 3.0 tuners, Televisions will start coming with them in 2018 or later if this new broadcast content standard becomes a consumer market reality. Furthermore, while ATSC 3.0 is not designed to be backwards compatible with ATSC 1.0
http://4k.com/news/fcc-pushing-for-...-over-the-air-4k-broadcasting-with-hdr-18459/
Repeat after me: You cannot mix NTSC, DTV or ATSC 3.0 (or any other modulation scheme so conceived and so dedicated) on the same RF TV channel.
"By definition, each modulation scheme consumes an entire TV channel."
Re:
I thought that your entire reply was wholly obvious
From your official link noting I was never referring to synthesize HDR content my TV can do all that ,
ATSC S34-168r8 Video – HEVC 17 January 2017
13
6.3.2.3 HLG transfer characteristics
For HDR video with the HLG transfer characteristics, the following constraints apply
I asked about more spectrum vis a vis another RF transmitter and RF spectrum or not since you maybe disputed that one transmitter can not do that If I understood correctly prior to reading just above here for simultaneous 480i/HDTV and ATSC 3.0 2160p up to HDR HLG that obviously combined may not fit in a single regulated HDTV channel HEVC notwithstanding at any decent quality below the lower nyquist rate .
Some background you may have a misunderstanding here you may not know beyond what I can read on the web about HLG HDR and ATSC 3.0 anyway as for the other maybe thats debatable this is not my career and I'm not familiar with you .
I understand at an enthusiast level with an electronics education in the late 1960's to 1970 and practical knowledge ,brief TV bench work and some self study going forward PC's starting in early 1980's can build and fix same , some electronics at the board level ,ohm's law ,radio RF propagation and amatuer radio at in part maybe nearly FCC gen class but dated, enthusiast level and my education Digital discrete time signals and IPTV , mpeg compression and audio codecs ,HEVC and so on , electrical conductivity LCD panels ,nyquist rates lower nyquist rates , digital signal sampling ,perceptual lossy encoding , lossless encoding,noise shaping Dolby AC-4 and MPEG-H 3D Audio MPEG-2 / H.262 and MPEG-4 AVC / H.264 video codecs. MPEG-H HEVC / H.265 codec RF modulation and so on.
Not everything about any of this and not any of it at a career level but I can bench TVs ,PC , and some radios and so on ,
From another post of mine here something maybe speculative and factual in case you missed it , it's unofficial ,
AFAIK Hybrid Log-Gamma (HLG) is the ATSC 3.0 proposal under consideration maybe you know something my web links don't or no ? .
** HLG is supported by HDMI 2.0b, HEVC, and VP9 Freeview Play and YouTube.
HLG does not need to use metadata since it is compatible with both SDR displays and HDR displays. HLG can be used with displays of different brightness in a wide range of viewing environments.
** source -Wikipedia -
February 3, 2017 FCC Pushing for ATSC 3.0 Standard for Over-the-Air 4K Broadcasting With HDR
Some of the new broadcast content enhancements that would come with ATSC 3.0 implementation include the already-mentioned capacity for 4K resolution along with HDR (using new broadcast-friendly standards like Hybrid Log Gamma), higher frame rates for content, wide color gamut and even direct-to-mobile device broadcasts of next-generation over-the-air content.
All of these ATSC 3.0 enhancements are still a ways off and while the mainstream 4K TVs of 2017 that are now being released in the U.S don’t have ATSC 3.0 tuners, Televisions will start coming with them in 2018 or later if this new broadcast content standard becomes a consumer market reality. Furthermore, while ATSC 3.0 is not designed to be backwards compatible with ATSC 1.0
http://4k.com/news/fcc-pushing-for-...-over-the-air-4k-broadcasting-with-hdr-18459/
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From what I have read, ATSC will support one 4K UHD channel OR several HD channels and SD channels. (Looks like they have the same capacity as a sat transponder.) This is using the H.265 compression standard.
http://www.studiodaily.com/2016/11/how-atsc-3-changes-broadcasting-for-the-better-its-not-just-4k/
I have two adoption questions about UHD broadcasts:
1. Is one channel enough to support a station in a post-repack landscape?
There are relatively few one channel stations left. The battle cry of the ATSC 3.0 proponents has been about buddying up at least until DTV can be sunset (years away). Many of us have witnessed the push-back from DIRECTV temporarily taking channels down to support NFL Sunday Ticket and I'm pretty sure that the OTA dependent viewers aren't going to be any more accepting. As sad as it sounds, we live in a self-righteous world -- even when it comes to "free" stuff.
2. Are these "units" based on theoretical maximums using pre-compressed content or is this something they think they have some hope of achieving using real-time compression?
If you can't present live events like championship sports in UHD until after the DTV sunset, will they be able to sell consumers on upgrading? The mandatory transition to DTV took several years and the first deadline had to be extended by a few months. Why would anyone assume that a voluntary transition would go much faster absent the "big win" of something noticeably better (i.e. DTV's HD with surround sound versus NTSC's best SD and stereo sound)? I assume that UHD sports video at 24fps isn't going to be a killer app.
1. Is one channel enough to support a station in a post-repack landscape?
There are relatively few one channel stations left. The battle cry of the ATSC 3.0 proponents has been about buddying up at least until DTV can be sunset (years away). Many of us have witnessed the push-back from DIRECTV temporarily taking channels down to support NFL Sunday Ticket and I'm pretty sure that the OTA dependent viewers aren't going to be any more accepting. As sad as it sounds, we live in a self-righteous world -- even when it comes to "free" stuff.
2. Are these "units" based on theoretical maximums using pre-compressed content or is this something they think they have some hope of achieving using real-time compression?
If you can't present live events like championship sports in UHD until after the DTV sunset, will they be able to sell consumers on upgrading? The mandatory transition to DTV took several years and the first deadline had to be extended by a few months. Why would anyone assume that a voluntary transition would go much faster absent the "big win" of something noticeably better (i.e. DTV's HD with surround sound versus NTSC's best SD and stereo sound)? I assume that UHD sports video at 24fps isn't going to be a killer app.
