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Poor man's document camera for videoconference

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Re: Poor man's document camera for videoconference

#31

Post by dharma1 »

montroser wrote: post #8

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…

Notes has a good document scanner on iOS - https://support.apple.com/en-us/HT210336

Google Photoscan mentioned by someone else is also great, it's available on iOS and Android

It takes a series of photos, and guides you to move the phone as the document is illuminated from different angles by the led flash. It then blends them for optimal result to eliminate glare

Re: Poor man's document camera for videoconference

#32

Post by nothrabannosir »

montroser wrote: post #8

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'm surprised nobody has mentioned Scannable yet, by Evernote. I use it regularly: it's a simple and pleasant marvel of technology. Free, no account, point your camera at a doc and it somehow recognizes it, snaps a pic and makes it look just like a document scan, no shadow no nothing. Share as PDF or image. Miles ahead of Apple's "import scan from iPhone" feature, even though it predates it.

I don't have an Evernote account but I'd definitely pay a few bucks for this app if they pulled up a paywall.

Re: Poor man's document camera for videoconference

#34

Post by JacobDotVI »

ckdarby wrote: post #7
kohtatsu wrote: post #6

Re. orientation: the phone shouldn't be trying to determine landscape/portrait when flat; it should gracefully keep the previous state for at least a dozen degrees. On my 11 Pro it doesn't change until ~40 degrees of attitude.

In Android there's an option to lock orientation.

Not all video apps respect the lock orientation setting

Re: Poor man's document camera for videoconference

#37

Post by lotsofpulp »

gtufano wrote: post #24
lotsofpulp wrote: post #20

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.

I just did it on an iphone 6S Plus and an iPhone XS both with ios13+, and while in landscape, if I press lock rotation, it changes to portrait and then locks it.

I’ve experienced this since iPhone 3G or iPhone 4, so I assume this is how they have designed it.

https://discussions.apple.com/thread/8237975

This website shows a workaround for it:

https://www.igeeksblog.com/how-to-lock-rotation-in-iphone-la...

Re: Poor man's document camera for videoconference

#38

Post by mkl »

A stack of books with a couple of rulers under the top one works better - it's height-adjustable.

Moving a bit further up the quality ladder, I've just built myself a solid laptop/monitor stand out of plywood, and I'm going to attach a strut sticking out the back to hold up a webcam-as-document-camera and (when it arrives) an LED ring light.

There are actually a whole lot of cheap products based around the phone-as-document-camera idea, e.g. https://www.aliexpress.com/item/4000309823825.html, a stand, phone holder, and ring light.

Re: Poor man's document camera for videoconference

#39

Post by duncans »

montroser wrote: post #8

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....

Re: Poor man's document camera for videoconference

#40

Post by app4soft »

duncans wrote: post #39
montroser wrote: post #8

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....

For Android there are few fully free & open-source alternatives.

I use OpenNoteScanner.[0,1]

[0] https://github.com/ctodobom/OpenNoteScanner

[1] https://github.com/yeyeto2788/OpenNoteScannerPDF

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