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> DisplayPort is packet-based and can be multiplexed with other USB-C traffic through a hub This is part of why DP is $$$ compared to HDMI. I would love to se

> DisplayPort is packet-based and can be multiplexed with other USB-C traffic through a hub This is part of why DP is $$$ compared to HDMI. I would love to see DP start eating HDMI's lunch after this and the absolute shit show that was the HDMI 2.0 roll out but cheaper to implement is almost certainly going to be the driving factor when it comes to consumer grade TV / Displays and no console or other set top box maker is going to bother putting display port on their device if nobody's got a TV that can use it.

tverbeure 3y ago
> This is part of why DP is $$$ compared to HDMI. Why is that more expensive? In terms of complexity, implementing DP vs HDMI 2.1 is not materially different. They both have fixed rate links, packets, Reed-Solomon forward error correction, DSC, etc. But IIRC DP is royalty free, and HDMI is not.
- refulgentis 3y ago
  It sounds like it might be more about "the market will pay more for the packet-based approach, and we shall charge what the market will bear"
  - tverbeure 3y ago
    Speaking about 'packet-based approach', the way it's presented in the popular press as if it's similar to Ethernet, is a pretty gross distortion, the impact of which is not nearly as much as people seem to think it is. You can check that there in this presentation (https://www.vesa.org/wp-content/uploads/2011/01/ICCE-Presentation-on-VESA-DisplayPort.pdf https://www.vesa.org/wp-content/uploads/2011/01/ICCE-Present...), page 32 and 33. The majority of DP traffic is still brute force video data, interspersed with heavily packetized secondary data. Over the years, I've spent many hours wading through DisplayPort data debug traces, and I've always wondered what people were smoking when they called it 'packetized like Ethernet'. It's just not true. (And FWIW: even old HDMI can transport secondary data packets just the way you can with DP. It's how audio-over-HDMI is done...)
  - autoexecbat 3y ago
    Perhaps there is just more scale for HDMI making it easier to recoup r&d for new components that implement it
babypuncher 3y ago
It won't happen unless VESA gets serious about adding home theater specific features to DP that HDMI has had for 20 years.
- kiwijamo 3y ago
  For example...? My experience is that DP is excatly like HDMI from the end user's perspective but happy to learn more.
  - ThatPlayer 3y ago
    ARC and CEC come to mind. ARC probably isn't too important, but CEC is nice being able to control various boxes with the same remote. Or being able to control the TV's volume with another remote.
    - babypuncher 3y ago
      ARC is actually pretty important, especially now that eARC is a thing. It finally decouples your receiver's HDMI capability requirements from your TV.
      - simoncion 3y ago
        I see no __technical__ reason why you couldn't do CEC over the AUX channel... all that's required is for the software on either end to be updated to squirt and interpret the bits, and it's a low-speed protocol, so it'll fit just fine in the AUX channel. "ARC" seems to be "Audio over HDMI using CEC for discovery and control", which (if you've bothered to run CEC over the DisplayPort AUX channel) you get the rest automatically with DisplayPort. However, because both CEC and ARC are HDMI standards, you bet your biscuits that the HDMI Consortium will bar anyone who wants to use HDMI ports on their devices from shipping official firm/software that does the braindead-simple thing of running CEC over DP AUX, and having ARC-compatible firm/software. As is nearly always the case (and when it's not, it's not for long) DisplayPort is totally capable of everything HDMI is, but the HDMI Consortium stands in the way of having commercially-distributed DisplayPort "home theater" products that are compatible with the nice-to-have HDMI features.
kimixa 3y ago
And the HDMI is pretty much a direct digital translation of analogue CRT signalling, blanking and timing weirdness included. Which is also not how modern LCDs implement their internal screen driving, so needs a similar level of complexity to decode and convert. I think the biggest difference in DP vs HDMI cost is simply scale - there's probably orders of magnitude more HDMI chips sold than DP.

tverbeure 3y ago

> This is part of why DP is $$$ compared to HDMI. Why is that more expensive? In terms of complexity, implementing DP vs HDMI 2.1 is not materially different. They both have fixed rate links, packets, Reed-Solomon forward error correction, DSC, etc. But IIRC DP is royalty free, and HDMI is not.

refulgentis 3y ago
It sounds like it might be more about "the market will pay more for the packet-based approach, and we shall charge what the market will bear"
- tverbeure 3y ago
  Speaking about 'packet-based approach', the way it's presented in the popular press as if it's similar to Ethernet, is a pretty gross distortion, the impact of which is not nearly as much as people seem to think it is. You can check that there in this presentation (https://www.vesa.org/wp-content/uploads/2011/01/ICCE-Presentation-on-VESA-DisplayPort.pdf https://www.vesa.org/wp-content/uploads/2011/01/ICCE-Present...), page 32 and 33. The majority of DP traffic is still brute force video data, interspersed with heavily packetized secondary data. Over the years, I've spent many hours wading through DisplayPort data debug traces, and I've always wondered what people were smoking when they called it 'packetized like Ethernet'. It's just not true. (And FWIW: even old HDMI can transport secondary data packets just the way you can with DP. It's how audio-over-HDMI is done...)
- autoexecbat 3y ago
  Perhaps there is just more scale for HDMI making it easier to recoup r&d for new components that implement it

babypuncher 3y ago

It won't happen unless VESA gets serious about adding home theater specific features to DP that HDMI has had for 20 years.

kiwijamo 3y ago
For example...? My experience is that DP is excatly like HDMI from the end user's perspective but happy to learn more.
- ThatPlayer 3y ago
  ARC and CEC come to mind. ARC probably isn't too important, but CEC is nice being able to control various boxes with the same remote. Or being able to control the TV's volume with another remote.
  - babypuncher 3y ago
    ARC is actually pretty important, especially now that eARC is a thing. It finally decouples your receiver's HDMI capability requirements from your TV.
    - simoncion 3y ago
      I see no __technical__ reason why you couldn't do CEC over the AUX channel... all that's required is for the software on either end to be updated to squirt and interpret the bits, and it's a low-speed protocol, so it'll fit just fine in the AUX channel. "ARC" seems to be "Audio over HDMI using CEC for discovery and control", which (if you've bothered to run CEC over the DisplayPort AUX channel) you get the rest automatically with DisplayPort. However, because both CEC and ARC are HDMI standards, you bet your biscuits that the HDMI Consortium will bar anyone who wants to use HDMI ports on their devices from shipping official firm/software that does the braindead-simple thing of running CEC over DP AUX, and having ARC-compatible firm/software. As is nearly always the case (and when it's not, it's not for long) DisplayPort is totally capable of everything HDMI is, but the HDMI Consortium stands in the way of having commercially-distributed DisplayPort "home theater" products that are compatible with the nice-to-have HDMI features.

kimixa 3y ago

And the HDMI is pretty much a direct digital translation of analogue CRT signalling, blanking and timing weirdness included. Which is also not how modern LCDs implement their internal screen driving, so needs a similar level of complexity to decode and convert. I think the biggest difference in DP vs HDMI cost is simply scale - there's probably orders of magnitude more HDMI chips sold than DP.