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This audio cable business is getting out of hand...

mansr

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The HDMI spec is 50'.
Which page of which version of the spec?

And a singal coax still carries dozens of HD channels for long distances. My diy coat hanger antenae thru 100' of coax gives me the best HD picture/5.1 surround I can get (better than cable, netflix, youtube) other than bluray, and it picks up 10HD channels, so why was expensive HDMI needed? Does anyone know how this HDMI scam got started?
HDMI carries uncompressed video. Compressed video uses about 0.1 bits per pixel, so that comparison isn't valid.
 

RayDunzl

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Cbdb2

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Which page of which version of the spec?


HDMI carries uncompressed video. Compressed video uses about 0.1 bits per pixel, so that comparison isn't valid.

Ive installed hundreds of TVs in large venues and never seen an HDMI cable over 50' and sometimes those didnt work properly. OTA HD uses a lot less compression than cable tv. A coax can carry 69 channels of compressed ( 19b/s ) HD that looks almost as good as Bluray, but you say it cant carry 1 channel of uncompressed HD. Not buying it. And I was actually touting network cable, cat6, as the way to go. Cheap and you can have 300' runs.
 

mansr

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Ive installed hundreds of TVs in large venues and never seen an HDMI cable over 50' and sometimes those didnt work properly.
That doesn't mean you're not allowed to make a longer one if by some miracle you manage to pull it off. An Ethernet cable isn't allowed to be longer than 100 m as then the maximum propagation time would be exceeded.

OTA HD uses a lot less compression than cable tv. A coax can carry 69 channels of compressed ( 19b/s ) HD that looks almost as good as Bluray, but you say it cant carry 1 channel of uncompressed HD. Not buying it. And I was actually touting network cable, cat6, as the way to go. Cheap and you can have 300' runs.
Blu-ray has a maximum data rate of 54 Mbps (and most discs use only half of that). Broadcast TV and streaming rates are much lower. HDMI 2.0 supports up to 6 Gbps per channel for a total of 18 Gbps. Again comparing compressed and uncompressed video formats is meaningless. Also bear in mind that HDMI predates Cat-6 cable and 10GBASE-T Ethernet by several years. Granted, the early HDMI versions, based on the DVI spec from 1999, had a maximum combined bit rate of "only" ~5 Gbps. 1000BASE-T Ethernet was also standardised in 1999.

From its introduction through to the present, HDMI has offered substantially higher data rates than contemporary networking standards. It is no surprise, then, that the cables are a little more expensive.
 
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M00ndancer

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From its introduction through to the present, HDMI has offered substantially higher data rates than contemporary networking standards. It is no surprise, then, that the cables are a little more expensive.


I have one really high-speed unit @ home, my VR helmet, but that thing "only" needs 12 Gbit/sec to display things. It would be so nice to have a Cat 8 @ 25Gbit instead of that really bulky HDMI 2.0.
HDMI is still a !"#¤!"##¤%"#¤%"#%¤ when it comes to compatibility. There is still so much crappy units that don't seems to talk properly, I hate HDCP. Things that losing the handshake is not fun. I talking to you cable box/satellite box makers! Don't get me started on the connector it self.
 

mansr

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I have one really high-speed unit @ home, my VR helmet, but that thing "only" needs 12 Gbit/sec to display things. It would be so nice to have a Cat 8 @ 25Gbit instead of that really bulky HDMI 2.0.
HDMI is still a !"#¤!"##¤%"#¤%"#%¤ when it comes to compatibility. There is still so much crappy units that don't seems to talk properly, I hate HDCP.
HDMI has become a morass of optional features and half-baked implementations, that's for sure. I can still see where it came from, and it made sense at the time. Now the interface is kept, with enhancements, in order to maintain compatibility. On the desktop, DisplayPort has pretty much replaced DVI/HDMI as monitor interface.

Things that losing the handshake is not fun. I talking to you cable box/satellite box makers!
The TV makers as just a much to blame. I used to work for a satellite box company. Sometimes we'd get reports of trouble with certain TV models. The cause was usually the TV not following the spec properly, and we'd have to implement a workaround.

Don't get me started on the connector it self.
Have you forgotten about the SCART connector?
 

Cbdb2

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That doesn't mean you're not allowed to make a longer one if by some miracle you manage to pull it off. An Ethernet cable isn't allowed to be longer than 100 m as then the maximum propagation time would be exceeded.


Blu-ray has a maximum data rate of 54 Mbps (and most discs use only half of that). Broadcast TV and streaming rates are much lower. HDMI 2.0 supports up to 6 Gbps per channel for a total of 18 Gbps. Again comparing compressed and uncompressed video formats is meaningless. Also bear in mind that HDMI predates Cat-6 cable and 10GBASE-T Ethernet by several years. Granted, the early HDMI versions, based on the DVI spec from 1999, had a maximum combined bit rate of "only" ~5 Gbps. 1000BASE-T Ethernet was also standardised in 1999.

From its introduction through to the present, HDMI has offered substantially higher data rates than contemporary networking standards. It is no surprise, then, that the cables are a little more expensive.

Why would it matter that HDMI can do 18 Gbps when bluray puts out 54Mbps. Do you use a fire hose to water your plants? Bluray data rate have been nothing for networks for the last 10 ( maybe 20) years. And now that almost every TV and HT reciever already has network capability the HDMI is redundant. You could attach everything to your network including your bluray and stream it or your downloads or netflix or your music or your computer desktop to any TV/music system in the house. Not to mention network control of everything. So why do we need HDMI?
 
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M00ndancer

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Have you forgotten about the SCART connector?
I had... now I'm going to have nightmares for weeks. Amiga -> Scart with RGB support or DVD player with RGB and not YUV support.
The list goes on. Wiggle, wiggle big fat cable now you're loose again.
 

mansr

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I had... now I'm going to have nightmares for weeks. Amiga -> Scart with RGB support or DVD player with RGB and not YUV support.
The list goes on. Wiggle, wiggle big fat cable now you're loose again.
Don't forget the lacerated fingers and bits of plug remaining in the socket.
 

DonH56

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I had totally forgotten about that one, probably because over here it was an EIA connector so I hardly ever heard "SCART". Don't speak French. Hated the connector no matter where it came from. The cheap ones would leave whole pins in the receptacle. What a mess. Not a bad idea at the time but needed a whole lot more real-world testing.

Sort of like HDMI...

I am still and forever in contempt of RCA connectors; who thought it was a good idea to make signal before ground on insertion, then break ground before signal on withdrawal? I suspect a conspiracy among amplifier and speaker manufacturers to sell more of them...

Great, now I can have nightmares about three connectors from one stinkin' post. I hate you all. :D
 

mansr

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I am still and forever in contempt of RCA connectors; who thought it was a good idea to make signal before ground on insertion, then break ground before signal on withdrawal? I suspect a conspiracy among amplifier and speaker manufacturers to sell more of them...
I don't think they were intended to be inserted or removed with the equipment powered.
 

DonH56

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I don't think they were intended to be inserted or removed with the equipment powered.

Alas, I am but imperfect, and have in the primordial past heard the dreaded 120+ dB buzz when I forgot to mute an input or turn off the amp first. Or when my kids did when unplugging something to plug in their game boxes.
 

wwenze

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Yes, compressed video over ethernet, wifi, or TCP/IP or UDP in general is starting to be popular

It also has 100ms of lag. More if it's Google Stadia.

USB also can have compressed video and uncompressed video versions, but the VR helmets are usually using uncompressed/low-compression USB3 if possible (for the camera), because again, latency.

End of the day we still need interfaces for uncompressed video, simply because encoding video + sending it over a low-bandwidth interface + decoding a video adds latency. 30ms of input (e.g. mouse) to video latency can make your life miserable. Also the last time I checked, 50Mbps 1080p60 H.264 recording using nVidia Shadowplay still uses chroma subsampling a.k.a. the red text in my games are all blurred. Even if we can get around the subsampling issue, lossy compression inevitably cause visual quality loss by eliminating high-frequency data (from a data analysis perspective).
 

mansr

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USB also can have compressed video and uncompressed video versions,
USB3 has the bandwidth for fairly high resolution uncompressed video. To complicate matters, the Type C connector also allows switching to alternate modes, including HDMI and DisplayPort, by repurposing the superspeed pairs.
 
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