Your answer wont be found in monitors. You need a media switch, a good one like thise used in the enteraimment industry for broadcast-quality transitions between inputs. Alternatively, look into streamer-quality "media switches" used by streamers with multiple camera rigs.
Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?
101–110 of 185 posts
Re: Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?
#102Earlier quoted context omitted.
It was really jarring when I got my M1 Pro MacBook and switching resolutions on the internal display was literally instant. No black screen between the switch whatsoever, it was just there. Makes you wonder what else we've been missing out on all this time.
It's because Macs (almost) always output the native resolution of the display. What you are changing is the draw resolution or scaled resolution.
That may technically true, but on the Intel MacBooks, switching resolutions was still a major ordeal with multiple black screens flickering past.
Re: Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?
#103You need a video matrix such as:
https://www.lindy.co.uk/audio-video-c2/matrix-switches-split...
Re: Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?
#104OK, remember when modems were like EEEEEEEkRrRrRrRrRrRrRbaBONGbaBONG.... That was handshaking, and it was how modems figured out which speeds and protocols each other supported so they could figure out how fast to transfer data and how to encode it. Monitors are kind of the same. There's handshaking that goes on each time you connect a monitor to a video source. Like (and I'm totally making this up): - Hi, I'm an AMD…
But why does it take a couple of seconds? I can send a ping thousands of kilometers away and get the ICMP reply in 100 ms or something. I can ping my router in less than a millisecond and my router is further away than my computer. Why does this whole negociation take seconds and not milliseconds? Or my car: it's full of electronics. Chips and code everywhere. Even my pedals, which used to be cables decades ago, are…
Ping: your device, your router, your ISP's router, etc are already up and running and ready to participate in protocol interactions. Having done a bit of networking in the days where it was still reasonable to use analog modems as backup connectivity, I remember waiting 15-30 seconds for dial out + negotiation to occur before ping replies began flowing again.
Car: your car is an integrated system where all the components have been selected with the intent of working together as an integrated system. A display device often supports many modes and has very few guarantees about how sources will behave, thus inter-device negotiation is needed upon connection.
As other comments have noted, the control channel is fairly low bandwidth and there is potentially a decent sized chunk of info to exchange, plus timeouts and delays to ensure the display can work with older or less featured sources.
Re: Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?
#105This has been annoying me since I first tried a PC after using Atari computers since they were a thing. No matter what monitor I use, it will take for ever to switch input port or just a simple change of resolution. I was used to be able to switch resolution several times per frame, you could make a game with low resolution and color on the upper 3/4 of the screen and have the stats in higher resolution 4 color mode…
One of the reasons why you could switch modes mid-frame is because the concept of a "video mode" is fundamentally different on a PC than on an Atari or Amiga. On a PC, ever since the EGA, the adapter can output at different horizontal and vertical scan rates and the monitor can adapt to the requested mode from the video card. That's why switching video modes takes a couple seconds and may involve a "click" or two. Up…
No. I have a Sony G520 CRT monitor with a hardware switch. When I flip the switch, the other image appears in less than a second. In the past I had a Samsung (I don't remember the model) that made the switch without even interrupting the electron beam, in mid-frame. First 2 frames were garbage, until it sync'd to the new signal, but it only took a blink of an eye to switch (at 85 Hz). It was also very quick to sync after a mode change. I could see BIOS screens that modern flat displays are to slow to display before they dissapear.
Re: Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?
#106This is one thing I really miss about analog tv. You could switch channels as fast as you could press the button. Everything now is so slow.
My current (Samsung) display is a pain to switch off . If I forget and switch the PC off first, it goes to sleep and starts blinking its annoying bright blue LED, which I managed to disable when it's on or off, but not when it's asleep. To get it to switch off I have to wake it up, wait until it cycles through all its inputs, gives up and shows me the menu, from which I can finally turn it off.
I'd plug the thing into a switched wall socket!
Re: Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?
#107You'll need a fancy KVM switch that does more than merely acting much like a physical switch would. Something like this should probably work: https://www.rextron.com/product-4K-2-Port-Full-Frame-PBP-KVM... Edit: The one above is merely the first one I found, not a recommendation. Be aware that such things may incur extra latency, since it's not just passing signals through, but rather processing them and repackaging…
As an aside: does anyone know the deal with Rextron, Extron, and Crestron? What’s going on with the names there?
They're all a play on the word "electron", which is the subatomic particle that CRTs would fire at the phosphorous screen to produce an image.
Re: Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?
#108There are hardware limitations that make what you're asking for impossible. Use software solutions if you actually need instant switch. But you probably don't.
> But you probably don't.
What does this statement add, beyond conveying that you don't personally care what the OP wants?
Re: Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?
#109Earlier quoted context omitted.
What are the hardware limitations? Surely this is possible if there was investment and interest in making this work? Or do the protocols really not allow this?
Most of the delay is I/O bound. Handshaking happens over the Display Data Channel (DDC) which is a protocol over I²C (a two-wire comunication bus). HDMI/DP/DVI have 2 dedicated wires inside the cable for this, USB-C has to switch over to use differential signaling on pins A8 and B8, and then switch back after communication is done. The bandwidth of that bus is small indeed, but most of the latency comes from artifici…
Naively it seems like you could optimise this at least for the second and subsequent switches: you could detect if the cable corresponding to the input you've previously switched to has been reconnected since last switch. If it hasn't, then you could re-use the previous EDID values for the device.
You'd obviously want this to be optional for special cases, but would that work, if implemented in a monitor or KVM?
It's not so much the delay that's annoying, but the renegotiation with something which is so obviously the same device.
Re: Ask HN: Can you recommend an “instant-switch” Monitor? Does one exist?
#110I was annoyed by this too. My solution was to buy a 49" samsung monitor and have either 50:50 or 1/3:2/3 split on the screen so I can see both at once. If I only want one active I can change the source but this has the flicker/delay as noted. I run Barrier software on both to move one keyboard and mouse between the screens.
Doesn't this split incur some horrible scaling artefacts? Does it work well even
for text?
I have a similar function on my LCD monitor and its basically useless, it seems it throws away 50% of the pixels or something.