Book Scanner

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Note - this tool is no longer hosted at the Hackerspace, this page is for historical purposes only. If you are interested in a replacement for it, bring the discussion up on the atxhs-discuss mailing list.

How to use the Austin Hackerspace book scanner (instructions v2.3.0)

Bookscanner hero promo.jpg


First, some caveats

  • The book scanner is calibrated (white balance, glare protection) for the exact location it is currently sitting in. If it needs to be moved, I will have to come in and recalibrate it. Please post to atxhs-members if it is moved.
  • The book scanner is a little fragile. The glass currently mounted in it seems to shift a little over time, and the cradle under it is not tightened down when not in use, and the cameras are attached only by a few turns of a tripod mounting screw, etc. Please be careful with it, and around it.
  • The book scanner can only scan books with pages of 8.5"x11" or smaller. Larger books will have an unusable amount of glare. Sorry.
  • Paperbacks will take longer to scan than hardcovers.
  • You will have to bring in a USB drive to download your photos, formatted as FAT16 or FAT32. ExFAT will not work. You cannot use your own SD cards in the cameras, nor can you use a computer to download photos from the cameras over USB.
  • Do not remove the SD cards from the cameras.
  • These instructions are a little complicated right now, but they will get simpler over time, as we improve the scanner configuration.
  • If you are uncomfortable with any of these instructions, email Vitorio, or the atxhs-discuss list, and we'll set up a time to come in and help you scan your stuff.

How the scanner works

The book scanner has two digital cameras pointing down at a V-shaped glass platen. The book sits in the cradle underneath the platen. The cameras run special software, and are controlled by a small computer.

The book scanner in the server room as of Apr 13 2014


With your right hand, you pull the handle down, which raises the book up, and flattens the pages against the glass. With your left hand, you press a key on the keyboard, which makes the cameras take pictures of the pages. You raise the handle back up (with your right), turn the page (with your left), and repeat the process until you've photographed every page of the book.

Then, you plug your USB drive in, download the photos, and erase the photos from the camera so the next person can scan their books.

How to actually do that

0. Prerequisites

  • A USB drive with plenty of free space. Depending on the book, a photo of each page can run 2.5MB, 5MB, 7MB or more. You must have a USB drive to download the photos onto. You cannot provide your own SD cards, take out our SD cards, or connect to the cameras directly over USB.
  • Time and patience. It can take several seconds, to ten or fifteen seconds or more, to photograph a page. There's several minutes of set up and tear down time. This is not an automated system.
  • A way to post-process the photos. At the end, you will have a folder of left-facing images, and a folder of right-facing images. The scanner does not turn them into a PDF, ebook, etc. This guide does not cover that, either.
  • Supervision (for non-members). As with any Hackerspace equipment, members are welcome to follow this guide and use the scanner unsupervised, but non-members must be accompanied by a Hackerspace member.

1. Check the scanner and cleaning supplies

  • If you gently lift up the blackout curtain draped over the top of the book scanner, you should see two cameras, each with a white USB cable and a black AV plugged into the side, and power wires coming out near the tripod screw on the bottom. Both cameras should have their mode dial at the top set to "P" for program mode.
  • There should be compressed air nearby for lightly dusting the cameras and cradle, and you'll want to get some glass cleaner and paper towels ready, so you can clean the glass platen. (Check the bathrooms if there isn't any near the scanner.)
  • The brown power switch behind scanner should turn the lamp inside the scanner on.
  • The LCD monitor should turn on when you press its power button.

If any of these things do not exist, are different, or do not happen, you should red-tag the scanner and post to atxhs-members.

2. Turn things on

The power to the book scanner should already be on, even though the monitor and lamp may be off. If the Raspberry Pi has its lights on, then the scanner already has power:

The Raspberry Pi controlling computer has power.


If it doesn't, turn the power on by turning on the power strip behind the book scanner:

The main power switch for all the book scanner hardware


To the left of the book scanner, is the brown power switch for the scanner's lamp. Turn it on:

The power switch for the scanner lamp


To the right of the book scanner is the monitor. Turn it on:

The LCD power button


To be safe, reset the controlling computer by hitting Ctrl-Alt-Del on the keyboard.

Reboot the Raspberry Pi


Gingerly reach in under the blackout curtains and turn each camera on by pressing the on-off button on top (the left-most of the three buttons).

Turn each camera on by pressing the on-off button on top (the left-most of the three buttons).


The overhead lights in the server room should already be off, but if they're not, turn them off.

3. Check and clean the platen

Run your finger along the bottom of the "V"-shaped platen glass. The two pieces should meet evenly. If one piece has fallen a little, gently push it back up. They're just held in with screws and foam, so don't risk breaking them: unscrew the droopy side (on both sides of the scanner), push it back in place, and then screw it back in. (If you crack the glass, everyone will be very upset with you, and you won't be able to scan. Sorry.)

Book Scanner's V-shaped glass platen


With the scanner lamp on, you will be able to see all of the fingerprints, smudges and smears on the glass. Dust the scanner itself off with a duster, then use glass cleaner and paper towels to clean both sides of each pane of glass. If the glass is not perfectly clean, you will be able to see it in every photograph, and smears and smudges will cause extra glare on your pages, making them illegible.

4. Set up the monitor and controlling computer

To make sure you can tell when the cameras screw up, the monitor has picture-in-picture. If you can't already see the camera on the monitor, turn PIP on by pressing the second button from the left and then exit the menus by pressing the third button from the left.

Turn on PIP with the second button from the left
Exit the menus with the third button from the left


You can switch between the left and right cameras using the AV switch.

1 is the left camera, 2 is the right camera


On the rest of the screen, you will see three options in white:

Press   1   to download photos from cameras
Press   2   to delete photos from cameras
Press any other alphanumeric key to take photos

Press "2" on the keyboard to erase any old photos on the cameras. Then, press any other key (spacebar is a good choice) to start taking photos.

For stability, the system will then reboot the cameras. Turn the cameras back on (again) when prompted, and hit any key (again).

When the system says it is ready, check both cameras (press 1 and 2 on the AV switch to change between them) to make sure you can see the cradle. It should look like this:

A properly working camera


If instead you see a menu in the way, it means the camera setup messed up.

This camera is wrong


If you see a menu, press the blue playback button ([>]) on that camera. Watch the monitor to make sure it goes away; sometimes it comes back and you have to press it again.

The blue playback button


5. Position your book

Pull the handle up to lower the cradle down. Open your book up to the middle and place it on the cradle, nearer to the back. Pull the handle down to press the pages against the glass. With the handle down and the pages against the glass, check the camera PIP on the monitor to make sure the book is centered horizontally on the screen. If it's not, pull the handle up, adjust the book, pull it down, and check again. Remember to switch between both cameras using the AV switch.

If the book doesn't sit well in the cradle, pull the handle up, and you can actually take the whole cradle out. That thing that rolls back and forth just lifts right out of there. The left and right sides of the cradle are detachable wings. Adjust them so the space between them is a hair larger than the spine of your book, then tighten the wingnuts a little to keep it from moving around. Put it back in place and center your book again.

6. Take pictures of pages

Finally.

With your right hand, pull the handle down to lift the cradle up and press the pages against the glass. The V-shaped platen should dig right into the spine of the book.

Book scanner lever in down position.


On the screen, you will see:

Press   ESCAPE   to stop taking photos
Press any other alphanumeric key to take photos

With your left hand, press any key on the keyboard. The server room is loud, but you should be able to hear two fake shutter clicks as the cameras take their photos. When the cameras are done taking their photos, you will see that message repeat.

With your right hand, pull the handle up to lower the cradle down. With your left hand, reach in and turn the page.

Book scanner lever up lowers the cradle to allow you to turn the book page.


Repeat from the top of step 6.

Note: sometimes the cameras will screw up. You can occasionally switch between them using the AV switch to see how they're doing, but the controlling software should detect a failure and kick you out to the main menu. This will force you to reboot the cameras. You won't lose any photos! Just press any key (besides 1 or 2) to start taking photos again, and it'll restart the cameras and set them up again.

7. Download your pictures

When you are all done taking photos, press "Esc" on the keyboard.

Turn off the scanner lamp using the beige power switch. You can also turn the overhead lights back on.

You will see three options in white:

Press   1   to download photos from cameras
Press   2   to delete photos from cameras
Press any other alphanumeric key to take photos

Press "1" on the keyboard. Plug your USB drive into the extension cable "Your USB stick." The computer will auto-detect it, create a directory, and download the photos from the cameras to it. This may take a while.

When it is done, it will report:

It is now safe to remove your USB stick

Remove your USB stick. You will see three options in white:

Press   1   to download photos from cameras
Press   2   to delete photos from cameras
Press any other alphanumeric key to take photos

Press "2" on the keyboard to erase your photos.

Instructions on how to turn your stack of "left" and "right" pages into an ebook, PDF, or whatever, are left as an exercise for the reader.

8. Finishing up

If you're going to scan another book, you can start over from step 4.

When you're done scanning, turn the lamp and the monitor off. Leave the main power switch on. Leave the server room's overhead lights off.

Future work

  • The cradle seems to be slightly crooked, the right side closest to you seems to bow to the right a bit. Sorry.
  • The cameras don't seem to be perfectly centered across from the raised platen any more. Were they ever? Is the guide tape wrong?
  • The glass probably needs to be replaced with museum glass.
  • The cameras shutter speed can be improved by fixing the focus.
  • The paper residue from the paint not being dry all over the scanner needs to be cleaned up.
  • A duster, glass cleaner, and towels need to be by the scanner at all times.
  • A drop cloth needs to cover the entire scanner when not in use to keep it clean.

Technical notes

  • The book scanner is a DIY Book Scanner "Hackerspace kit," ordered pre-cut with assembly hardware directly from their shop, rather than taking the open source plans and having them cut on a Shopbot.
  • The cameras are Canon PowerShot A2200 digital cameras, taking 12-14MP JPEG photos.
  • The cameras are running CHDK 1.2.0-3659 (stable), booting from an 8GB SD card.
  • The cameras are set in Program mode, ISO 80, white balanced against a sheet of white paper pressed against the glass platen with the scanner lamp on and overhead lights off and blackout cloths in place, center brightness, no flash, "Fine" quality.
  • You'll get approximately 350dpi photos from the scanner.
  • The controlling computer is a Raspberry Pi model B+ running NOOBS, Raspbian, and custom controlling software, available here: https://github.com/vitorio/diy-bookscanner

Other stuff

  • DIY Book Scanner Dorkbot Austin September 2013.pdf Vitorio gave a presentation at Dorkbot Austin in September 2013 about the book scanner