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A comment on In spite of an increase in Internet speed, webpage speeds have not improved. Parent comment

Re:In spite of an increase in Internet speed, webpage speeds... by iforgotpassword on Tuesday August 04, 2020 @02:19PM (#24052889)
While I can see the technical reason why channel changes take a while with digital TV, I've always wondered why switching the digital input of your TV, or just changing the resolution of the connected devices takes so long. On most TVs it's over two seconds. The signal is in most cases just a stream of standalone, uncompressed frames. Switching from HDMI1 to HDMI2 should take a few milliseconds.
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Re:In spite of an increase in Internet speed, webpage speeds... by kergonath on Tuesday August 04, 2020 @03:58PM (#24053888)
I’ve always assumed that’s because TV manufacturers choose the most under-powered SoC they can get away with, don’t put half as much RAM as it needs, and let loose incompetent programmers who don’t have to use the damn thing ever. Still very frustrating.
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Re:In spite of an increase in Internet speed, webpage speeds... by gregmac on Tuesday August 04, 2020 @02:29PM (#24053014)
There's a lot going on: HDCP handshake, resolution negotiation, HDMI-CEC setup..

HDCP obviously being consumer-hostile, but the others are decent features to make things "just work".

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Re:In spite of an increase in Internet speed, webpage speeds... by iforgotpassword on Tuesday August 04, 2020 @02:40PM (#24053149)
Ok so HDCP might be an explanation although I wonder if it has any impact if it's not in use. Don't really know how it works tbh.

As for the rest: Resolution negotiation is optional and wouldn't matter if the device is already outputting at some resolution, also this happens on different pins, so even if the device would first query the EDID of the TV to figure out what mode it prefers, the TV could meanwhile already display whatever the device is outputting. Same with CEC, this is another protocol on different pins than where the picture data is sent. HDMI really is just DVI with some extras, at least for the older versions.

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Re:In spite of an increase in Internet speed, webpage speeds... by Dylan16807 on Tuesday August 04, 2020 @02:57PM (#24053313)
Why didn't it already do all of that, before I told it to switch inputs?
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Re:In spite of an increase in Internet speed, webpage speeds... by formerly_proven on Tuesday August 04, 2020 @03:51PM (#24053811)
I don't know why (but would be interested), but even PC screens are usually very slow at switching (>1 second delay), and for some inexplicable reason practically all of them turn their backlight off while doing it.
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