README

*** NOTE: This file is out of date ***

== Pre-installation checklist ==

* bash (tested with 2.05b)

* python (tested with 2.3.4)

* sed for installation configuration

* Something to start the script e.g.
  vcron (or another crond that can run commands at startup)
  /etc/rc.local file
  init with agetty (or getty with similar capabilities)

* sane-backends
* sane-frontends (for scanadf)
* ghostscript (for ps2pdf)
* netpbm (for pnmtops)
* imagemagick (for convert, if using monochrom)
* PIL - python image library (if using monochrome.py)

optional
* use a separate keyboard on a ps2 mouse port with ps2key 
  http://www.arava.co.il/matan/misc/


== Installation ==

* copy config.sh.sample to ~/papscan.sh and customize

* update paths for new installation; run
  $ su - scan
  $ make config
  in script directory, where "scan" is the user the script will be run as
  (requires permission to access scanner)
  
* add something equvalient to this to /etc/inittab
  c7:3:respawn:/sbin/agetty -n -l "/path/to/initscan.sh" 38400 tty7 linux
  then 
  # init q

* (optional) use chvt (part of kbd) to switch to the right virtual console 
  on boot
  e.g. put "/usr/bin/chvt 7" in rc.local

== Image conversion notes ==

=== Lineart ===

In pdf files JBIG or CCITT fax compression can be used for monochrome images.
pnmtojbig (from netpbm) for info on jbig implementation
ps2pdf will use CCITT compression if it detects a monochrome postscript files.
convert -resize needs to use the Point -filter to remain in monochrome.
reportlab doesn't appear to use CCITT compression

iso paper sizes in points
http://www.cl.cam.ac.uk/~mgk25/iso-paper-ps.txt
http://www.cs.wisc.edu/~ghost/doc/gnu/7.05/Use.htm#Known_paper_sizes

convert experiements (with ImageMagick 6.0.7)

-contrast doesn't seem to help much
experimented when using -monochrome (from gray mode scanned image)
  gamma - use
    all with gamma 2
    contrast - no change?
    dither - no change?
    enhance - slightly worse
    equalize - much worse
    modulate 120 - slightly better, mainly for text on coloured background
    modulate 100,50 - no change?
    modulate 100,150 - no change?
    modulate 120,150 - better as above
    all with gamma 2 and modulate 120
      normalize - text slightly more blurred
  gamma vs modulate
    gamma 2.5 looks clearer than modulate 180

  reducing to 2 colors looks slightly better in gimp (2.0.4)
    image -> mode -> indexed -> Use Black and White Palette and 
                                                           No Colour Dithering

=== Grayscale/Color ===

Can use DCT/JPEG compression in pdf files.
Can't seem to set the level of compression used (e.g. 75% etc)


=== scanadf redesign ===

running a program at the end of each page scanned --scan-script option

add new swithes for
  piping data to a command for each page scanned
  running a program at the end of the scan <- wait for command to terminate