Detect Page position of huge book

Infrared QR codes.

>>1024487
since it's a book, pages will be stacked onto each other so I don't think it'll work, as I don't think an infrared QR code can be read through 10 other pages.

>>1024490
>>>1024487
>since it's a book, pages will be stacked onto each other so I don't think it'll work, as I don't think an infrared QR code can be read through 10 other pages.

But why would you want to detect the other pages when they're not being displayed?

An infrared QR code on every page would probably do what you want. Your system scans the code and projects the necessary page, turn a page and the next QR code is displayed and the loop starts again.

>>1024517
yes but where would the scanner be?
that's my main problem since it requires direct visual contact

>>1024486
Don't use rfid, use IR diodes on the top corner of each page and count them on the camera on each sied of the book.
Or, you know, use strings and pulleys mounted to one side

>>1024486
Or use what was proposed few comments above, with QR codes and scan from above.
With good camera it would need to be only few centimeters to the front and a meter above the book jtself.

File: verso-printed-presentation-binder-and-tabs-gi36.jpg (215KB, 800x800px) Image search: [Google]

215KB, 800x800px

>>1024518
Maybe you could tell us where it can be, since there seem to be limitations you haven't mentioned.
What about using tabs on pages and detecting those optically? Or use a bunch of hall sensors + magnets and mark the pages with pieces of steel foil (maybe on backside).The sensors could be under the book.

>>1024526
>>1024525
>>1024527
well as I said it's gonna be a giant book screwed to a table, with a projector on the ceiling above it, so like 2-2.4m above.
I want to avoid detecting things optically from the top because users are gonna touch it, put their hands on it, press specific zones of the page etc.... so I don't want pages to flip if a finger comes in front of a tag / IR diode.
same goes for basic steel foil, if someone put their hand on it and have a wristwatch I don't want it to turn pages or something, that's why I want something a little more foolproof

>>1024528
>projector on the ceiling
So the scanner would be next to it, for example.
>so I don't want pages to flip if a finger comes in front of a tag / IR diode.
Filter the results then. No page detection or nonsensical detection = do not change page.
>same goes for basic steel foil
Tiny magnets then.

>>1024532
the thing is, no page detection = do not change page means the transition would only start when the page has already been flipped, which is a bit weird. Being able to detect when a page has been lifted means the transition can follow and it feels more "real" as you can have a simple fading while the user flips the page, giving a smoother transition.

>Tiny magnets then
same thing, I don't want someone to come with a bracelet that's held with magnets to fuck up it up, it might sound picky but lots of people are going to use it and that means there's bound to be a couple of them with stuff like that

>>1024528
so its something like a virtual book, with mostly blank pages and content or some parts of it projected onto it?
>>1024537
>Being able to detect when a page has been lifted means the transition can follow and it feels more "real"
what about lifting the page a little but not flipping over yet? or sliding the page parallel to the book then flippin git over?
if you want to differentiate those edge cases correctly you need to be google or pay some kid to sit there and push a button

or add a solid frame to the pages so you can easily detect all possible states of flipping with a potentiometer and initiate the switch based on the angle of a page and its speed

>>1024551
yep, book with totally blank pages and you project something on it.
with RFID tags, lifting the page a little but not flipping it causes no problem at all, as it either does nothing if it's still close enough, or if you lift it out of the sensor's range, it'll see that a page was lifted but since there are sensors on each side it'll detect that it hasn't been put down yet. I'm not google and I intend to buy a chinese kid right now so this is quite neat.

and the point of this is to add a real physical feel to it, adding a frame to the pages makes it pointless, I might as well just throw a touch screen with a pdf, this is meant to give a "real book" feel with big pages that you turn and shit

>>1024537
There will always be a period where the page is ambiguous and you're projecting something else than the user thinks is appropriate. Well, unless you make everything pointlessly elaborate or hire that button pusher kid.

>bracelet that's held with magnets to fuck up it up
Several magnets, far apart from each other, detect a pattern instead of single magnet.
Get RFID or loss prevention tag readers with very short range / modify existing ones for short range / make your own.
Use tabbed pages and scan the QR codes or whatever behind the pages from below.

I don't want to be the only person here to have considered this: have you thought about, oh, actually printing the information on the book?

Or is some of the page content interactive/video /other?

>>1024568
from below is gonna be hard because wel, several pages are going to rest on top of each other.
and I don't know much about RFID, how would you modify one to make it have a shorter range? that's why I asked here in the first place


>>1024569
yes, it has videos, animations and touch sensors

>>1024571
>from below is gonna be hard because
That's why tabbed pages, so that the codes won't get obscured.
>how would you modify one to make it have a shorter range?
Aluminum foil around the reader.
Shorted wire loop or a metal plate in front of the reader.
Resistor in series with the reading coil or in parallel with it.

>>1024584
didn't see that, tabbed pages aren't an option for design reasons (not my decision to make)

>Aluminum foil around the reader.
>Shorted wire loop or a metal plate in front of the reader.
>Resistor in series with the reading coil or in parallel with it
I'll try that tomorrow, I'll have the old project to fiddle around with, including the RFID tags and sensors, thanks

Options:
- If the pages are rigid, embed a stiff wire into each page that runs through a slot in the spine, and embed mechanical or optical switches in the spine that you closed by the wire. You'll have a row of 20 switches. If you use two switches per page, you could detect if the page is on either side, and if a page is not detected on either side, you know the page is being turned.
- Use magnetic sensors like the ones used by security systems to detect if a door is closed. Embed a magnet in a different position on each page's edge. For each magnet, embed two sensors under the book, one on each side. You should be able to detect which pages are laying flat on each side, and if a page is not detected on either side, you know the page is being turned.

>>1024599
you just described what I described in my first post
RFID tag in each page, RFID sensor on the sides of the book etc....
except the problem is two sensors can't be too close or else they start fucking up.
as I said herer
>>>/g/55629498
i'll try to wrap tinfoil around them tomorrow to see if I can limit the fuckupery but I'd like a "cleaner" solution if someone thinks of something

>>1024601

Use induction. A thin wire coil in each page, and a "sensor" induction loop in each of the hardback covers.

You'll have to make your own paper with the wire embedded, or glue two sheets of paper together. Lots of high end limited run books use the two sheets of paper method, believe it or not. I have a book on my shelf on indigo dying from Japan that was a hundred copy run.

Anyway, then you would rig some way to measure the induction draw or resistance or whatever and have a custom little circuit that calculates how many pages are open for that draw.

>>1024625

As a fail safe it would be checking the page count on both sides, as a sort of checksup in case one side errored.

X resistance on side a, Y resistance on side b, looks like it's open to page 15