Reducing HDMI handshake time?

The place for all discussion on gaming hardware
Post Reply
User avatar
DirkSwizzler
Posts: 548
Joined: Fri Apr 28, 2017 8:23 pm
Location: Bellevue, Washington, USA
Contact:

Reducing HDMI handshake time?

Post by DirkSwizzler »

I forget where, but I recently saw someone mention that a game switching between resolutions will cause the display to go blank for a longer period of time if more than 1 device is downstream of the HDMI conversion.

I'm assuming there's truth to this. But can anyone confirm that it's actually true? I could easily see it just being a problem with the ADC process needing to rescan the input for an extended period of time. And nothing needing to be done downstream.

Assuming it's true. Can anyone suggest alterations to my current setup to reduce handshake/blank time while still maintaining flexible inputs to flexible outputs?

My current setup:
I've got my Framemeister (and OSSC when it arrives) hooked into a Zettaguard HDMI switch to allow my newer consoles to join the analog devices at a single output point. I then have that switch hooked up to a Zettaguard HDMI splitter to send one output to my HDTV and one output to my 144hz PC gaming monitor when the big tv is in use (or perhaps for lower latency gaming if I ever compare the two devices).

I honestly didn't put a ton of time researching the switch and splitter and just went based on what seemed to get good reviews on Amazon and vaguely seemed future proofed a bit if I hook up more things in the future.
User avatar
citrus3000psi
Posts: 668
Joined: Wed Dec 25, 2013 11:56 pm
Location: Indiana

Re: Reducing HDMI handshake time?

Post by citrus3000psi »

I can't help with the the handshake. But I'd double check your HDMI splitter for lag. I have tested a few and have yet to find one that doesn't add noticeable amounts of lag.
User avatar
BuckoA51
Posts: 3424
Joined: Sat Oct 02, 2010 10:08 am
Location: Ireland
Contact:

Re: Reducing HDMI handshake time?

Post by BuckoA51 »

That's somewhat controversial, I've never detected any lag with any HDMI splitter.
OSSC Forums - http://www.videogameperfection.com/forums
Please check the Wiki before posting about Morph, OSSC, XRGB Mini or XRGB3 - http://junkerhq.net/xrgb/index.php/Main_Page
User avatar
citrus3000psi
Posts: 668
Joined: Wed Dec 25, 2013 11:56 pm
Location: Indiana

Re: Reducing HDMI handshake time?

Post by citrus3000psi »

BuckoA51 wrote:That's somewhat controversial, I've never detected any lag with any HDMI splitter.
I'm not talking about a switch, but a 1 input with 2 output. Just to clarify.

This is one I have with noticeable amounts of lag.
https://www.amazon.com/gp/aw/d/B01IGIK1 ... UTF8&psc=1
User avatar
DirkSwizzler
Posts: 548
Joined: Fri Apr 28, 2017 8:23 pm
Location: Bellevue, Washington, USA
Contact:

Re: Reducing HDMI handshake time?

Post by DirkSwizzler »

I finally got around to testing with 240 test suite on an av famicom with nes advantage controller (led lights up on button press) and iPhone 6 slow mo.

I wasn't thorough enough to upload to a pc where I could step each video frame by frame. But eyeballing 10 tests per configuration failed to find a difference between the switch+splitter setup above and a direct connection to the framemeister.

I was getting 3 frames of lag routing to my 144hz pc monitor. And 5 to my samsung tv in game mode.

Although in hindsight I was so preoccupied with lag that I didn't test the topic to see if switching modes had a blank time difference. Will do hopefully tomorrow night.
User avatar
BuckoA51
Posts: 3424
Joined: Sat Oct 02, 2010 10:08 am
Location: Ireland
Contact:

Re: Reducing HDMI handshake time?

Post by BuckoA51 »

I'll have to crack out the Leo lag tester and try some HDMI splitters I have around here. I can't see why a splitter would need a frame buffer though.
OSSC Forums - http://www.videogameperfection.com/forums
Please check the Wiki before posting about Morph, OSSC, XRGB Mini or XRGB3 - http://junkerhq.net/xrgb/index.php/Main_Page
User avatar
tjstogy
Posts: 341
Joined: Tue Sep 01, 2015 1:27 am
Location: New York

Re: Reducing HDMI handshake time?

Post by tjstogy »

It’s rude to shake hands with an hdmi cable
Ikaruga11
Posts: 1457
Joined: Thu Apr 07, 2016 1:32 pm

Re: Reducing HDMI handshake time?

Post by Ikaruga11 »

HDMI has hands?
User avatar
opt2not
Posts: 1289
Joined: Fri May 20, 2011 6:31 pm
Location: Southern California

Re: Reducing HDMI handshake time?

Post by opt2not »

That's what the H stands for.
User avatar
DirkSwizzler
Posts: 548
Joined: Fri Apr 28, 2017 8:23 pm
Location: Bellevue, Washington, USA
Contact:

Re: Reducing HDMI handshake time?

Post by DirkSwizzler »

Tested blank times with 240p test suite on a PAL gamecube and a scart cable. Just using the alternating 240p/480i test.

The switch and splitter combo mentioned above seemed to have no effect on the blank times. And I was unable to find a framemeister setting that had any effect. Reading earlier today led me to believe that cheating the EDID protocol might have helped. But nope.

I was reliably getting 7s of blank time to my samsung tv (through a receiver). And 5.25 to my 144hz gaming monitor. And those numbers held up even when both were active with the splitter.

Still would love to hear if anyone has tips for reducing those times. I'm hoping the OSSC will be an improvement over the framemeister.
ZellSF
Posts: 2726
Joined: Mon Apr 09, 2012 11:12 pm

Re: Reducing HDMI handshake time?

Post by ZellSF »

It's a problem at the XRGB-mini's end. It will always take that long to switch resolution. The OSSC will switch instantly, it's up to the rest of your devices how long it will take to switch resolution.

Neither of my cheap HDMI splitters have made any significant difference in input lag or resolution switching delay. The latter is definitely possible though. My 8 port HDMI switch will add a few seconds and my AVR (that really only extracts audio from HDMI) will delay it by like 10 seconds. If you're trying to minimize switching times with the OSSC you might have to replace a splitter or switch.
pyroman512
Posts: 43
Joined: Sat Jan 14, 2017 3:40 pm

Re: Reducing HDMI handshake time?

Post by pyroman512 »

ZellSF wrote:It's a problem at the XRGB-mini's end. It will always take that long to switch resolution. The OSSC will switch instantly, it's up to the rest of your devices how long it will take to switch resolution.

Neither of my cheap HDMI splitters have made any significant difference in input lag or resolution switching delay. The latter is definitely possible though. My 8 port HDMI switch will add a few seconds and my AVR (that really only extracts audio from HDMI) will delay it by like 10 seconds. If you're trying to minimize switching times with the OSSC you might have to replace a splitter or switch.

Agreed, there is nothing that can be done about the framemeister slowly switching resolutions.

Have you gone deep into your TV settings? I have noticed over the years that a few tvs I have had all direct connections btw, reacted differently to this issue. My first HDMI enabled TV (I loved it so much, any connection you could name was on there) would switch instantly but the next Vizio I got would go blue for a split second then be ok. Most notable on PS3 which I had set to 1080p but most games I had were apparently 720p.

My current TV is a Samsung JU7100 which in my opinion is phenomenal as far as my abilities can tell. With the framemeister and careful adjustments to all the settings I actually have less than 2 frames of lag using the 240p test. All my profiles are 720p to work better with 4K.

Oddly enough though If I use the 240p test suite, I have run some of those resolution tests and it somehow screws up my tv settings. The crucial one is that is turns Game mode off. I can't figure that out though but it is really annoying. Anyways even if you have game mode on, take a quick check at some of the other settings that could still be enabled like MPEG noise filter or Digital clean view. These apply to my Samsung but may not apply to yours.
Post Reply