scanning and downloading at the same time

[jancoj]

Hi all,
This is such a great forum. I am new here and I am planning to build my own book scanner. I have been looking through but I couldn´t find any topic about taking pictures and downloading them directly to the computer from camera at once . Is any solution how to do that. If anybody knows where I can find more please give a link. I am planning to buy two Canon A495 cameras.
Many thanks for any help and for all ideas and pictures of book scanners.
jancoj, Slovakia

[Gerard]

have a look at ptpcam-gui

http://chdk.wikia.com/wiki/PTP_Extension

i was planing to use a simular solution,

[jancoj]

Thank you Gerard for the quick respond. Does anybody any experiences of using this kind of scanning? Is this process much slower than just take pictures on the SD card?

[Gerard]

my experiences is that even just taking pictures to sd-card can be to slow (canon a495 with class 10 sd card)

if your scanner is solid (my is not solid thats why i have to wait 1 sec after lowering the plattern) and the pages a easy to change,

[Gerard]

Hi, i've made some progress with my a495 and capture and downloading with one click, and it seams that it is quite fast

here is the ptpcam/bash script witch i used

Code: Select all

#!/bin/bash

ptpcam=$HOME/Dokumente/robo-chdk/chdk-de/tools/ptpcam/ptpcam

#put cam in mode 1 if it is in mode 0
$ptpcam --chdk="luar get_mode()" | grep -q -E "\d*:ret:false" && $ptpcam --chdk='mode 1'

#shoot the image
$ptpcam --chdk="lua shoot()"

#determin the last image handle
lastimghandle=$($ptpcam -L | tail -2 | head -n 1 | awk '{print $1}')
$ptpcam --get-file=$lastimghandle
$ptpcam --delete-object=$lastimghandle


update:
the script has a problem, it is downloading the last before the shoot image, so your a always one behind (maybe it is not a problem)

i've tied to fix this behavior but then the scipts gets slower and the cam writing and reading of the image need to be synchronised

[jancoj]

Hi Gerard,

Thank you for the script. I hope I can use it soon, but now I am struggling to get Canon A495 cameras, because they are out of stock in my country. I wait for one e-shop to confirm my order. If they do not confirm it i need to find another type of camera.

[Gerard]

i think you can use all kind of canons with chdk support

[jancoj]

That is true, but this one was really cheap...I found Powershot A800 for the same price but I think there is no CHDK for this camera yet...

[Tim]

En Eye-Fi card is an option, though it's $50 US for each card at least. http://www.eye.fi/products/compare-cards. The cheaper card seems to do enough for book scanning. I don't have any experience with their stuff though.

[Gerard]

I have 2 eye-fi sd cards, also an linux server for the cards

the main problem is, the cards waiting >9 seconds after the last write action from the cam before they starts to upload the images, so sanning and downloding at the same time is not posible (as long you dont make >9s breaks while taking images)