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Poor man's document camera for videoconference

info.iet.unipi.it

51–58 of 58 posts

Re: Poor man's document camera for videoconference

#51

> "With so many people and students around the world working from home, we really need some easy to deploy shared whiteboard solution. This is especially important for pre-college students who may not have access to high end hardware." Just add a new mode to videoconferencing, where both parties get a white screen and both can start drawing and the resulting image stays in sync on both clients? (I feel like this solu…

>> "With so many people and students around the world working from home, we really need some easy to deploy shared whiteboard solution. This is especially important for pre-college students who may not have access to high end hardware." >Just add a new mode to videoconferencing, where both parties get a white screen and both can start drawing and the resulting image stays in sync on both clients? (I feel like this solution is so obvious, I'm about to fly out a window - what am I missing?)

Author here.

There have been a few proposals in this space for the past 25 years including hangouts extensions, using a virtual camera that just exports the screen (if people remember the old mbone tools wb and vic; I myself wrote an extension to replace the camera with a snapshot from a configurable region of the X screen), and my own shared whiteboard which gives parties a shared screen that they can edit modify replay ...

http://info.iet.unipi.it/~luigi/wb/

There are two main reasons (in my opinion) why this space has been neglected:

- almost nothing matches the convenience, speed and _resolution_ of writing and drawing with an actual pen. Pads with sufficient resolution and decent lag are only appearing now, and they are fragile and expensive. Graphic tablets are cheap but lack the visual feedback and looking at the output on the screen still has significant latency. They are moderately usable, but takes time to get used to them, and you need a real 10+in screen to use them effectively. Using a finger or a conductive pen on a phone screen is only good for small sketches, not for writing longer sentences or formulas.

- the main users of such products would be non commercial entities (pre-college schools, students) so there are no paying customers. Even at college level lectures are increasingly based on slides prepared in advance. Businesses, of course, use slides or meet in person, and the whiteboard style of collaboration is generally done in person.

Social distancing now may actually create more use cases and perhaps returns (in terms of actual money or social appreciation) that stimulate software solutions to appear.

The Apollo13 problem still stands: even if we had good and cheap technology for writing, at this time it would be impossible to build and sell such products to customers, so we have to find solutions that use hardware already in possession of the users.

Re: Poor man's document camera for videoconference

#52
post #24

Earlier quoted context omitted.

Only for portrait mode. Never made sense to me why they only allow locking in one orientation and not landscape.

It's "lock rotation", not "lock portrait". If you have the device in landscape when you lock it, it will lock in landscape.

No, the feature is called "Portrait Orientation Lock" - it will only lock it in portrait mode and not landscape.

https://support.apple.com/en-us/HT204547

Re: Poor man's document camera for videoconference

#53
post #28

Earlier quoted context omitted.

You flip it landscape and turn off autorotation.

When my phone was updated to Android 9, that toggle became force-portrait. If I enable it now, it immediately turns back to portrait and disables rotation.

I'm on AOSP Android 10 and it works as I described. Can't remember the behaviour on 9. Have a good one.

Re: Poor man's document camera for videoconference

#54
post #51

> "With so many people and students around the world working from home, we really need some easy to deploy shared whiteboard solution. This is especially important for pre-college students who may not have access to high end hardware." Just add a new mode to videoconferencing, where both parties get a white screen and both can start drawing and the resulting image stays in sync on both clients? (I feel like this solu…

>> "With so many people and students around the world working from home, we really need some easy to deploy shared whiteboard solution. This is especially important for pre-college students who may not have access to high end hardware." >Just add a new mode to videoconferencing, where both parties get a white screen and both can start drawing and the resulting image stays in sync on both clients? (I feel like this so…

> "almost nothing matches the convenience, speed and _resolution_ of writing and drawing with an actual pen"

Absolutely agree, which is why I think attempting to reproduce that convenience on a digital system would be the wrong assumption to begin with. Pen and paper are special.

I think the issues you described in combination to the original solution I mentioned could be mitigated by dynamically increasing the image size. So instead of viewing the screen as your entire whiteboard, it grows as you add more drawings/notes to it. So for example, you have the phone and the white drawing board screen, you scribble f(x) = on the entire horizontal surface (thus circumventing the inherently low resolution issue of most touch-screens) and then the image width doubles and shifts your view to the newly created whitespace, and so on.

It's not a perfect solution, but I think it could and believe it would lead to the same desired results. It's a compromise between human convenience and adaptation to (pre-existing) physical machine restrictions.

On the topic of financing... maybe crowdfunding, then?

Re: Poor man's document camera for videoconference

#55
post #39

In these situations where you're taking a photograph of writing or a diagram on a piece of paper, it can be surprisingly tricky to get rid of the shading from the lighting conditions and be left with just the content on the page in high contrast. This explanation nails how to do it though: http://www.imagemagick.org/Usage/compose/#divide Divide a blurred copy by the original and you end up with effectively an adaptiv…

I really rate Microsoft's free Office Lens for document scanning. It automatically crops and there are a few filters you can experiment with to get the best result and the output to PDF or whatever. iOS: https://apps.apple.com/gb/app/microsoft-office-lens-pdf-scan... Android: https://play.google.com/store/apps/details?id=com.microsoft....

MS OL works surprisingly well with OneDrive on my iPhone. I frequently use this pipeline on my desktop instead of using my USB printer/scanner.

I've also used OL on Windows 10 (desktop) to crop images of documents sent to me from others. The GUI assumes you're using the app on a tablet, but it's workable.

I don't like the recent update to OL which added a carousel of images from my iPhone's stored photos. I use OL exclusively for business, so the carousel showing personal photos is idiocy.

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