What about an HDMI in?

I think the main people who would be interested in a HDMI In Expansion card are Streamers and Youtubers.
However having an Internal Capture card could be a selling point and Could have some Interesting Implications Like Transforming your laptop into an Extra Monitor. For example; if you build computers you can use it for your test bench and that could extend into more ideas like adding a keyboard and mouse external dongle using Bluetooth which I don’t think even exists besides setting up something like Synergy.

The smallest retail capture card I could find for reference was the GENKI ShadowCast.
5.08 x 4.88 x 0.94 inches according to Amazon but most capture cards are larger.
(~ 12.91 x 12.40 x 2.39 cm.)

Am I just crazy? is this even necessary? would you find something like this useful?
Let me know, I would love to hear what other people have to say.

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I am taking a look at this, it should be possible, I’ll keep you posted on it, the smallest USB C capture card type thing I could find is https://www.aten.com/global/en/products/usb-&-thunderbolt/content-creation/uc3020/

It should also be possible to compact something like this: HDMI to USB 3.0 Video Capture motherboard/PCBA circuit board|Transmission & Cables| - AliExpress maybe by double layering it or something, I can’t do PCB designs at all so this isn’t my strong suit, if anyone would like to help they’re welcome to!

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Good capture cards are a bit pricey and won’t easily fit inside the bay. I’m sure that Corsair won’t want these guys making elgato hardware in this form factor. Maybe if the laptop takes off they’ll do it.

I dont know how well these cheapo chinese adapters are, I can’t imagine they’re very good. You should also be away that viewing content that’s being transcoded has some serious delay on it, so you won’t be using it as a monitor for your switch or other console.

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That’s a good point.
My Guess after doing some research:
100 to 500ms of delay on the low end with sizing constraints
It still could be useful, I mean you could probably play Civ if you wanted to.
I’m not saying it’s perfect but with an HDMI splitter you could definitely play it on another screen and it’d be an alright and easy recording setup.

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+1 for this! I would love to have this for a raspberry pi while traveling.

However, I thought I remembered reading somewhere that HDMI also could have some kind of DRM implemented? (but sometimes a HDMI slitter removed this)

Does anyone know if CSI-2 can be exposed via thunderbolt or USB-c standard? If so, it might be fairly easy to use this chip Amazon.com

That component is used by this cool pikvm project to capture the video output of a server and send it over IP. This would obviously be a very hackey way to do it (and it very likely wouldn’t fit) but you could maybe implement the full pikvm and then see video over IP (created by a LAN chip connected via USB). This requires a pi zero to do hardware accelerated video encode and achieves fairly good frame rates (presumably higher that 10-15 fps since this says it will decrease to this rate when not using hardware encoding Working with video - PiKVM Handbook)

Disclaimer- I know very little about this topic, just throwing out ideas :sweat_smile:

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It has to be a way. I have always wanted to use a mini PC (barebone) from conferences and classroom (connected via VGA/HDMI to a projector) while using mi Laptop or Windows Tablet as Main / Extension Monitor.

There are several startups ideas around that can inspire o help to research about it:

Nexdock
Mirabook by Miraxess
Phonebook by Anyware

Those use a similar idea: Video Input from a mobile. But imagine using as main/second monitor from any device… limitless possibilities. :wink:

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This would be an AMAZING gadget for anyone working in IT!
Making the laptop into a keyboard and mouse and display for a server, or switch, or what have you.
Or Raspberry PI for developers and tinkerers <3
This is already implemented in another laptop Linus has covered like a day ago:
GPD Pocket 3

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I own a DiskioPi (DIY 10" tablet based on a RPi type SBC) that has this functionality.

The way it has been achieved is the display panel itself has two HDMI inputs (on its controller board), one is tied to the SBC and the other brought outside the case as HDMI in, then the unit power switch is a 3 position (on, off, display only).

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Just posting that I would also be interested in an hdmi in expansion card. Or even better an Hdmi card that can do both in/out based on mode selection (in bios, software driver, or manual hardware switch next to port).

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You just went from something easy to something a lot harder

Heh, I’d be happy with just hdmi in, but one can dream…

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Alternative 1: How about going straight to the monitor and adding a second input that is direct to the screen instead of going through the pci/mainboard. Have a keyboard shortcut to switch inputs.

Alternative 2: Have the framework mainboard connect to the screen using usb c and provide some ability to convert/mount third party screens . We could then upgrade our screen with any portable monitor product (ex: asus zenscreen) that would fit into the framework frame. There are a lot of options in that space (screens with batteries, screens with touchscreen/pen input). This would give framework users a lot of upgrade options without framework having to design and manufacture a bunch of different screen products.

That would need a major mainboard change and some creative abuse of usb-c pins.

As someone who has bolted usb-c screen to a laptop, I can sat that isn’t a very normal user friendly thing to do but yeah more screen options would be nice.

There are single-chip HDMI-to-USB solutions like the MS2130, which should fit in an expansion module. Unfortunately documentation for that chip is rather sparse (read: does not publicly exist at all), but there is this open-source design that makes use of it: GitHub - YuzukiHD/YuzukiLOHCC-PRO: Low cost USB3.2Gen1 HDMI-USB Video Acquisition With Loop Out (Loop Out HDMI Capture Card) base on MS2130 & MS9332

That project also has an HDMI splitter and loopback output, which won’t fit in an expansion card and have to be removed. MS2130-based capture devices can also be found en masse on aliexpress, they sell for around 10-20€.

Based on the schematic for the project I linked above, it looks like a SPI EEPROM is also required (the repository contains a firmware binary).

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Do note that the part you linked is under an NDA, so I really don’t think they should be posting all the files for it.

Hmm, I don’t see any.

(Just like Chinese companies who regularly pretend copyrights, NDAs and anything else they wish just doesn’t exist)

We’ve taken a look at that part (based on non-NDA information), and have concerns about latency.

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I have one of the USB 3 capture dongles using the MS2130. It does have more latency than the built-in screen, but it’s not unusably slow either.

EDIT: at least in guvcview latency is minimal, in OBS it’s a lot worse

A bigger issue is that there are seemingly some graphical artifacts introduced by the capture card – the top-most line in the captured image is always black (or close to black), while the 2 right-most columns are a bit brighter than they should be.

for the right formfactor/footprint, I would absolutely spring for a card that could handle 4k60input.

Physics and BoM might prevent that from being moderately priced.

I would love this.

If i could connect a laptop and use it as a monitor with mouse and keyboard id buy one immediately.

Remote desktop is disabled at work due to security concerns, so i cant use it, but a laptop thats effectivly remote desktop but wired. Oh my, id be very happy and very excited.

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