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What is exactly patented in Dolby Vision? There has to be some innovation to be patentable. HDR10 and HDR10+ exist.

jiggawatts 4y ago
Dolby Vision is poorly documented but I did find a long PDF explaining how it works. It does provide significant value worthy of patent protection. The main thing they did was develop a nonlinear color space designed so that each “bit” of information provides equal value. This way no bits are wasted, making compression more efficient and have fewer artefacts. The color space is also set up so that the “lightness” channel is accurate and brightness can be rescaled without introducing color shifts. They also came up with a way of encoding the HDR brightness range efficiently so that about 12 bits worth of data fits into 10 bits. The format also allows a mode where there is an 8-bit SDR base stream with a 2-bit HDR extension stream. This allows the same file to be decoded as either HDR or SDR by devices with minimal overhead. Last but not least they work with device manufacturers to make optimal mapping tables that squeeze the enormous HDR range into whatever the device can physically show. This is hard because it has to be done in real time to compensate for maximum brightness limits for different sized patches and to compensate for brightness falloff due to overheating. Early model HDR TVs had to have FPGAs in them to do this fast enough!
- suzumer 4y ago
  While Dolby did design the perceptual quantizer gamme (PQ) [1] that almost every HDR device today uses, they waived patenting it [2] when it was standardized in SMPTE 2084 [3]. Everything that is proprietary about Dolby Vision (everything except PQ gamma) is relatively mundane and just dynamic metadata. [1] https://en.wikipedia.org/wiki/Perceptual_quantizer https://en.wikipedia.org/wiki/Perceptual_quantizer [2] https://f.hubspotusercontent00.net/hubfs/5253154/Dolby%202084%20Patent%20Statement.pdf https://f.hubspotusercontent00.net/hubfs/5253154/Dolby%20208... [3] https://ieeexplore.ieee.org/document/7291452 https://ieeexplore.ieee.org/document/7291452
  - jiggawatts 4y ago
    People assume that some RGB matrix transform and a nonlinear PQ gamma is all Dolby Vision is. In practice it's an entire ecosystem of certifications, professional calibration of panels, efficient encoding formats, etc... To reproduce the end effect of Dolby Vision you'd have to have a team of people liaising with television manufacturers, and makers of production software like DaVinci Resolve. It's not a trivial task that can be done through open source. It's real work that costs money. We can all hope and wish for open standards, but it's a bit like trying to come up with an open architecture for a railway bridge. It'll still take real work to customise it to any particular valley, the local geography, and the specific requirements. Dolby Vision is similar. The mapping from the full signal range to each specific panel is a complicated thing that requires quite a bit of work to determine.
    - suzumer 4y ago
      You obviously know more about this than I do, but when I watch a a well encoded Blu-ray that doesn't use Dolby Vision like Planet Earth 2, and I compare that to a dolby vision encoded disc, I fail to see a noticeable difference. And when I rip the RPU of a disc that uses dolby vision and look at some of the data [1], I again don't see enough to warrant this being a proprietary system, especially when we have HDR10+. So Dolby may have teams of calibrators and created certifications, at the end of the day I fail to see why this warrants being proprietary. Please let me know what Dolby Vision does better than HDR10+ or regular HDR, because at the end of the day I'm just a hobbyist and want to learn more about this space. [1] https://pastebin.com/m5NfUTbc https://pastebin.com/m5NfUTbc
      - mvanbaak 4y ago
        This all depends on the system used to watch the content. From setting used on tv and avr and player, to the actual hardware. When i watch See and compare the DV version vs plain HDR version on my LG C1 the difference is big
        brokenmachine 4y ago
zokier 4y ago
https://en.wikipedia.org/wiki/BrightSide_Technologies https://en.wikipedia.org/wiki/BrightSide_Technologies HDR10 and all the other stuff came along much much later

Dolby Vision is poorly documented but I did find a long PDF explaining how it works. It does provide significant value worthy of patent protection. The main thing they did was develop a nonlinear color space designed so that each “bit” of information provides equal value. This way no bits are wasted, making compression more efficient and have fewer artefacts. The color space is also set up so that the “lightness” channel is accurate and brightness can be rescaled without introducing color shifts. They also came up with a way of encoding the HDR brightness range efficiently so that about 12 bits worth of data fits into 10 bits. The format also allows a mode where there is an 8-bit SDR base stream with a 2-bit HDR extension stream. This allows the same file to be decoded as either HDR or SDR by devices with minimal overhead. Last but not least they work with device manufacturers to make optimal mapping tables that squeeze the enormous HDR range into whatever the device can physically show. This is hard because it has to be done in real time to compensate for maximum brightness limits for different sized patches and to compensate for brightness falloff due to overheating. Early model HDR TVs had to have FPGAs in them to do this fast enough!

suzumer 4y ago
While Dolby did design the perceptual quantizer gamme (PQ) [1] that almost every HDR device today uses, they waived patenting it [2] when it was standardized in SMPTE 2084 [3]. Everything that is proprietary about Dolby Vision (everything except PQ gamma) is relatively mundane and just dynamic metadata. [1] https://en.wikipedia.org/wiki/Perceptual_quantizer https://en.wikipedia.org/wiki/Perceptual_quantizer [2] https://f.hubspotusercontent00.net/hubfs/5253154/Dolby%202084%20Patent%20Statement.pdf https://f.hubspotusercontent00.net/hubfs/5253154/Dolby%20208... [3] https://ieeexplore.ieee.org/document/7291452 https://ieeexplore.ieee.org/document/7291452
- jiggawatts 4y ago
  People assume that some RGB matrix transform and a nonlinear PQ gamma is all Dolby Vision is. In practice it's an entire ecosystem of certifications, professional calibration of panels, efficient encoding formats, etc... To reproduce the end effect of Dolby Vision you'd have to have a team of people liaising with television manufacturers, and makers of production software like DaVinci Resolve. It's not a trivial task that can be done through open source. It's real work that costs money. We can all hope and wish for open standards, but it's a bit like trying to come up with an open architecture for a railway bridge. It'll still take real work to customise it to any particular valley, the local geography, and the specific requirements. Dolby Vision is similar. The mapping from the full signal range to each specific panel is a complicated thing that requires quite a bit of work to determine.
  - suzumer 4y ago
    You obviously know more about this than I do, but when I watch a a well encoded Blu-ray that doesn't use Dolby Vision like Planet Earth 2, and I compare that to a dolby vision encoded disc, I fail to see a noticeable difference. And when I rip the RPU of a disc that uses dolby vision and look at some of the data [1], I again don't see enough to warrant this being a proprietary system, especially when we have HDR10+. So Dolby may have teams of calibrators and created certifications, at the end of the day I fail to see why this warrants being proprietary. Please let me know what Dolby Vision does better than HDR10+ or regular HDR, because at the end of the day I'm just a hobbyist and want to learn more about this space. [1] https://pastebin.com/m5NfUTbc https://pastebin.com/m5NfUTbc
    - mvanbaak 4y ago
      This all depends on the system used to watch the content. From setting used on tv and avr and player, to the actual hardware. When i watch See and compare the DV version vs plain HDR version on my LG C1 the difference is big
      - brokenmachine 4y ago

zokier 4y ago

https://en.wikipedia.org/wiki/BrightSide_Technologies https://en.wikipedia.org/wiki/BrightSide_Technologies HDR10 and all the other stuff came along much much later