What's going on with the BDA and 4K?

Discussion in 'Displays' started by Kevin Collins, Nov 4, 2013.

  1. Kevin Collins

    Kevin Collins Owner, from The Other Washington
    Owner

    Joined:
    Jan 14, 2007
    Messages:
    2,740
    Likes Received:
    69
    Location:
    Seattle, WA
    Real Name:
    Kevin Collins
    I had lunch today with one of my colleagues that has done standards work for video and audio since the DVD-Forum started back in the 90's.

    There were a couple of interesting tidbits that I thought folks here would be interested in:

    The BDA does have a 4K committee and has and still is working on getting BD to support 4K. Some of the challenges are with MPEG and SMPTE in regards to defining what minimum requirements there needs to be for BD 4K discs and for UHDTV's to support.

    One of those things is SMPTE's REC2020, the new, expanded color gamut that would supersede REC709 (used for HD content today). Along with that is the desire to increase bit depth of 8-bits per color to 12-bits per color and YCbCr with 4:2:0 chroma subsampling to 4:4:4. Why is that REALLY important? REC2020 (which I asked if it meant that I have perfect vision) would introduce a much larger color space that would be closer to what we see for colors today. The increase to 12-bits per color and 4:4:4 subsampling would essentially remove all banding that you see even with HD content today. A great example of this is underwater photography where the video is looking up to the sun. The gradations of blue have bands in it. This isn't solved with a higher bit rate.

    It's a given that the support for BD 4K would require a new player, just like 3D blu-ray did, but it would be backwards compatible. It is rumored that the new 4K BD players would have a HDD in them to allow for streaming downloads (aka Ultraviolet) that would allow the user to not purchase the optical disc. This would allow a user to have N movies on the HDD and just delete the ones that are not of utmost importance, similar to what you do with a DVR today. Of course, if you wanted the movie to watch again, you could just download it from your digital locker. I look at it as an insurance policy that BD player manufacturers can keep a market if people stop using optical disc and move to digital downloads. Kind of like those players back in the day that had both VHS and DVD...

    The other question is how do you fit all of this on a BD disc? Won't it require a new disc? Well, if it did, then it wouldn't be backward compatible with existing BD players, something the BDA has to do, or there won't be a market to move forward with. This pretty much means that BD discs would have to stay at two layers and have the max capacity at 50GB.

    There are a couple ways that all of this can come together. First, H.265, officially known as HEVC (High Efficiency Video Codec) which replaces H.264 officially known as AVC (Advanced Video Code). Geez, who on earth came up with those names?! According to my source, HEVC can do 4K at 20 Mbit/s without any problems.

    OK, so you can supposedly fit a 4K title on a BD50 disc. If it is being encoded in HEVC, how on earth does that disc work in existing BD players? It turns out that Dolby, yes the one that does audio, has a video technology that allows for encoding 1080P content to work in existing BD players and then a carrier track that is in HEVC that would be used in the new 4K BD players that would allow for 4K playback.

    Wow, this is sounding promising. When can I get my hands on it! Well, even if the BDA could get all of those starts to line up, there is the problem with UHD TV manufacturers.

    Turns out that UHD TV's today can only display REC709 and don't necessarily support 4:4:4.... I asked my friend about the Sony UHD TV that we showed from CEDIA and the media player with Sony 4K content on it. Turns out that Sony is encoding those 4K titles with AVC, 8-bits per color and 4:2:0 chroma upsampling and that the display doesn't support the REC2020 color gamut even if the titles were encoded differently.

    Sigh... Basically there still needs to be a lot of consensus between a bunch of different players to make this happen to the point that there would be something besides 4K content to really make the format something people could see.

    Notice I said could see. Turns out the BDA 4K committee is also looking at advanced audio technology to pull off things that would be more akin to Dolby's Atmos technology. So, in addition to seeing, people could hear some differences (if they spend the money for more speakers and amps).

    I walked into lunch thinking that I would become even less excited about UHD. Now I am quite excited IF everyone can agree to standards that actually make a difference.

    What are your thoughts? More interested or are plenty happy with HD content?
     
    DavidJ likes this.
  2. Everett Stallings

    Everett Stallings Supporting Actor

    Joined:
    Aug 24, 1998
    Messages:
    658
    Likes Received:
    97
    Location:
    Wilmington,De
    Real Name:
    Everett
    Price is a major point for me.
     
  3. Dr Griffin

    Dr Griffin Cinematographer

    Joined:
    May 30, 2012
    Messages:
    2,426
    Likes Received:
    1,389
    Real Name:
    Zxpndk
    What is the realistic timeframe for this? It sounds like it's still a few years away from the mass market. I am interested in 4K and OLED though, as an upgrade in probably 4 or 5 years.
     
  4. FoxyMulder

    FoxyMulder 映画ファン

    Joined:
    Sep 14, 2009
    Messages:
    5,236
    Likes Received:
    1,613
    Location:
    Scotland
    Real Name:
    Malcolm
    They have already stated the intent to use 100GB discs with an additional layer, they can now fit 33GB per layer, so three layers instead of two, this news came out back in September. Expect some disc content next year.

    The production lines are ready, they inadvertenly revealed all this. Three of links below.

    http://www.cdrinfo.com/Sections/News/Details.aspx?NewsId=37859

    http://www.hdtvtest.co.uk/news/4k-bluray-201309123318.htm

    http://www.techradar.com/news/home-cinema/next-gen-4k-blu-ray-discs-outed-by-manufacturer-before-official-reveal-1180491
     
  5. Kevin Collins

    Kevin Collins Owner, from The Other Washington
    Owner

    Joined:
    Jan 14, 2007
    Messages:
    2,740
    Likes Received:
    69
    Location:
    Seattle, WA
    Real Name:
    Kevin Collins
    Timeline is more based on all the parties coming together and agreeing on the specifications. This seems more complicated, particularly since UHD TV's are already shipping than what occurred with HD DVD and Blu-Ray. I spent three years working on the HD DVD specification and know first hand how hard it is to get consensus across all the parties. Given that Sony (a BDA member) has already started delivering 4K content with everything being the same except it being in 4K is somewhat concerning. If they change to what is being proposed, then that would mean that their early adopters would have an inferior product.

    So, I didn't get any real clue on when this would become viable. But I believe that the BDA realizes that the window of opportunity will shrink the longer they wait on doing this.
     
  6. Kevin Collins

    Kevin Collins Owner, from The Other Washington
    Owner

    Joined:
    Jan 14, 2007
    Messages:
    2,740
    Likes Received:
    69
    Location:
    Seattle, WA
    Real Name:
    Kevin Collins
    It isn't clear that they will do this, even though there is lines that can do multiple layers. As stated above HEVC is good enough that everything listed above can still fit on 50GB. If they actually deliver three layers for this, then it isn't clear how there would be backward compatibility with existing players to see the content in 1080P.

    Keep in mind that expanding to 100GB discs isn't just for BD, they believe that it can be used for storage purposes also.
     
  7. FoxyMulder

    FoxyMulder 映画ファン

    Joined:
    Sep 14, 2009
    Messages:
    5,236
    Likes Received:
    1,613
    Location:
    Scotland
    Real Name:
    Malcolm
    I believe they have 300GB planned for storage, i also think it's easy enough to release new players that can read three layers, have H.265 and have the new HDMI 2.0 spec, it's just the same scenario that played out with 3D where new players were required and they soon came down in price too, i don't see a problem with 3 layers, the tech is more than good enough now.
     
  8. JoeDoakes

    JoeDoakes Cinematographer
    Supporter

    Joined:
    Apr 1, 2009
    Messages:
    2,513
    Likes Received:
    655
    Real Name:
    Ray
    Thanks for telling us this. I didn't understand the bit below. What does it mean?
     
  9. Keith Cobby

    Keith Cobby Screenwriter

    Joined:
    Jan 8, 2013
    Messages:
    1,642
    Likes Received:
    782
    Location:
    Kent "The Garden of England", UK
    Real Name:
    Keith Cobby
    Interesting feature Kevin. I recently saw a programme on NHK HD about Sony's efforts in this area. They seem to be advanced in developing 4K and 8K for broadcast television. I am not sure how big the market would be for a 4K/8K packaged media. I am buying about 10% of blu-rays compared to DVD and if this follows through to a higher resolution format I probably wouldn't be buying that many given the remastering that would be necessary. I am inclined to think therefore that while higher resolution formats for home viewing are inevitable they might mainly be for broadcast and streaming etc.
     
  10. Sam Posten

    Sam Posten Moderator
    Moderator

    Joined:
    Oct 30, 1997
    Messages:
    20,846
    Likes Received:
    1,874
    Location:
    Aberdeen, MD & Navesink, NJ
    Real Name:
    Sam Posten
    Sounds like the horse designed by committee has already turned into one butt ugly camel by entrenched interests.That backup UV solution sounds stupid as a rock to me. Way to sabotage yourself by signaling to the consumer that this is already a dead avenue. They aren't stupid, consumers recognize today that Disks and Downloads and Streams all provide different and valuable services, mixing them together is in nobody's best interest.
     
  11. DavidJ

    DavidJ Producer
    Supporter

    Joined:
    Jul 23, 2001
    Messages:
    3,095
    Likes Received:
    231
    Real Name:
    David
    Thanks for the info Kevin.
     
  12. Kevin Collins

    Kevin Collins Owner, from The Other Washington
    Owner

    Joined:
    Jan 14, 2007
    Messages:
    2,740
    Likes Received:
    69
    Location:
    Seattle, WA
    Real Name:
    Kevin Collins
    I am not disagreeing with that point. What I am saying is that they don't want to do that as it will require EVERYONE to purchase a new player, even if they don't have a UHD TV. If they are smart they will want discs to be able to play both HD and 4K content, thus allowing the consumer to purchase one BD disc and be able to play on both regular and new BD players. Of course, only the new BD players would be able to play 4K. It's the same concept that they did with 3D Blu-ray. If they have three layer BD discs, it most likely will be impossible for existing BD players to play the HD version of the content from the disc.

    They will be committing suicide if they have a disc than can't play on both. People will just go to streaming 4K content -- not many consumpers are anal like the folks on this forum about the quality of the content. They go for the keyword "4K", and if there is 4K streaming, they will just move to that for their UHD TV's.

    Optical disc has a long road to hoe -- the carnage of this is clear -- Netflix pivoting and most of their revenue coming from streaming and today DISH shuttering the rest of Blockbuster.
     
  13. Kevin Collins

    Kevin Collins Owner, from The Other Washington
    Owner

    Joined:
    Jan 14, 2007
    Messages:
    2,740
    Likes Received:
    69
    Location:
    Seattle, WA
    Real Name:
    Kevin Collins
    I guess there are a bunch of studios (save Disney) that think otherwise. I have only activated one BD disc for UV, just to see what it was like. I have yet to spend the time to activate any other discs. If I could activate by playing the disc in a BD player, maybe I would do that. But taking my disc to where my computer is, logging into a site, entering a ridiculous key and then registering it is too much work for the invested time.
     
  14. schan1269

    schan1269 HTF Expert
    HW Reviewer

    Joined:
    Jul 4, 2012
    Messages:
    17,112
    Likes Received:
    899
    Location:
    Chicago-ish/NW Indiana
    Real Name:
    Sam
    If 4k goes stream only...I don't have the bandwidth for more than 15hrs of 720p a month.DOA for rural consumers.
     
  15. Kevin Collins

    Kevin Collins Owner, from The Other Washington
    Owner

    Joined:
    Jan 14, 2007
    Messages:
    2,740
    Likes Received:
    69
    Location:
    Seattle, WA
    Real Name:
    Kevin Collins
    I suspect and predict that 4K will largely come from streaming. The ATSC committee started work in the early 90's. It wasn't fully implemented until 2006 -- some 26 YEARS after it started. Look at how long it is taking the BDA to try to do 4K and then times that by 100 for anything the US government is involved in. Given the fact that spectrum is at a premium and there is a call to congress to take away existing utilized spectrum from broadcasters today, I don't find it feasible that a new 4K standard will emerge for OTA transmissions.
     
  16. Osato

    Osato Producer

    Joined:
    Feb 7, 2001
    Messages:
    3,063
    Likes Received:
    491
    Thanks for the post Kevin!

    Very interesting stuff!

    I am very curious to see where all of the technology is leading.

    I'm very happy with blu ray and HDTV at the moment, but again I do find UHDTV, 4K and 8K very interesting.
     
  17. Kevin Collins

    Kevin Collins Owner, from The Other Washington
    Owner

    Joined:
    Jan 14, 2007
    Messages:
    2,740
    Likes Received:
    69
    Location:
    Seattle, WA
    Real Name:
    Kevin Collins
    I suspect that UHD with OLED will become generally affordable in 3-4 years.
     
  18. Kevin Collins

    Kevin Collins Owner, from The Other Washington
    Owner

    Joined:
    Jan 14, 2007
    Messages:
    2,740
    Likes Received:
    69
    Location:
    Seattle, WA
    Real Name:
    Kevin Collins
    That's a point that concerns me also. But the proponets think that providers are going to remove cap limits (how they come to that conclusion is beyond me). But I actually haven't heard of people complaining about cap limits with streaming HD content. So, maybe it won't be an issue.

    In regards to bandwidth HEVC with 4K is supposed to be as efficient as AVC with 1080P.
     
  19. Kevin Collins

    Kevin Collins Owner, from The Other Washington
    Owner

    Joined:
    Jan 14, 2007
    Messages:
    2,740
    Likes Received:
    69
    Location:
    Seattle, WA
    Real Name:
    Kevin Collins
    There are a couple of parts that I am addressing above: color space, bits per color and chroma sub sampling.

    In regards to color space REC709 is a specification defined by SMPTE for HD content. Among other items in the specification, the part I am specifically referring to is the color space. Our eyes can see a substantially large colors space than what can be displayed on existing and UHD display devices. REC601 is the SMPTE specification for SD content and has a much smaller color space than REC709. Below is the defined color space for REC709:

    CIExy1931_Rec_709_svg.png

    REC2020 has a significantly larger color space:

    CIExy1931_Rec_2020.svg.png

    What does this mean? It means that there is more color saturation and a much more realistic picture compared to what we see today. Of course, it isn't clear how much previous film stock captured a color space compared to something like the color space defined in REC2020. However, it is an important component to attracting consumers as the content will have a deeper, realistic look. This isn't like goosing the control on the TV to make colors more saturated. I am referring to more saturation as actually going broader in the overall color spectrum.

    For the bits per color part (also known as color depth) is something that goes down to the pixel level. This is also something that is defined in SMPTE 2020 specification. Color depth is only one aspect of color representation, expressing how finely levels of color can be expressed (a.k.a. color precision); the other aspect is how broad a range of colors can be expressed (the gamut). What this means to the picture is what I referred to in the original post
    Chroma sub sampling is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance. For NTSC, DVD and Blu-Ray/HD DVD, the specification remained at 4:2:0 as it reduced bandwidth (i.e. storage) for the content to be transmitted or put on a storage medium. The concept came about because of the way the human eye works. The eye uses rods and cones to sense light; rods are very numerous and sense brightness (i.e., light and dark, or black and white and the shades of gray in-between) but rods can’t perceive color differences. Cones, on the other hand, see color; but cones are relatively few in number, and they’re coarser; we can see changes in brightness much more acutely than we can detect changes in color. Long ago, video engineers decided to take advantage of that quirk of human physiology and developed the now-common color sampling systems to save bandwidth, under the idea that “we wouldn’t really notice anyway.”

    The numbers N:N:N refer to the three components in YCbCr (remember the component cables that we used for DVD and BD/HD DVD players?). There were three cables that provided an analog signal (now sunset-ed as studios want to close the analog hole of illegal copying). Each cable had the three components. Y′ is the luma component (i.e. black and white) and CB and CR are the blue-difference and red-difference chroma components. Thus 4:2:0 indicates a rate of 4 luminance samples, 2 blue difference and 0 parts red difference.

    OK, so who cares? Well it is visually discernible for certain types of content. For starters you get more sampling for each pixel, actually identical average sampling. This provides more accurate color. You also get rid of blocky color edges --- which gets to some of the banding you see in gradients of the same color (i.e. the underwater example I was highlighting or a sunset seen over the ocean).

    Hope this helps! If I wasn't in the HD DVD forum for three years, I wouldn't know anything about it... :)

    The key point here is that these things need to be incorporated into BD 4K and UHD sets in order for people to notice / see a difference. Most consumers are not going to be sitting .6X distance of the height of the display to be able to resolve 4K.
     
  20. Keith Cobby

    Keith Cobby Screenwriter

    Joined:
    Jan 8, 2013
    Messages:
    1,642
    Likes Received:
    782
    Location:
    Kent "The Garden of England", UK
    Real Name:
    Keith Cobby
    My feeling is that consumers in the US/UK/Europe will be left behind by the Japanese and South Koreans.
     

Share This Page