# Last edited on 2008-02-04 20:17:42 by stolfi

This test uses grayscale images of an early Brazilian printed
book, provided by Geraldo Lino de Campos:

  ln -s ${STOLFIHOME}/IMPORT/images/docs/geraldo/n 
  
  Cropping and aligning the recto images:
  
    rm .check.ppm
    tifftopnm n/x0.tif \
      | pnmcut  6  5 1545 2155 \
      > /tmp/t-x0.pgm
    tifftopnm x1.tif \
      | pnmrotate +0.115 \
      | pnmdepth 255 \
      | pnmcut 10  8 1545 2155 \
      > /tmp/t-x1.pgm
    rgb3toppm /tmp/t-x0.pgm /tmp/t-x1.pgm /tmp/t-x0.pgm \
      > .check.ppm
    xv .check.ppm &
  
  Cropping and aligning the verso images:
  
    tifftopnm y0.tif \
      | pnmflip -lr \
      | pnmcut  8 12 1545 2155 \
      > /tmp/t-y0.pgm
    tifftopnm y1.tif \
      | pnmflip -lr \
      | pnmrotate -0.130 \
      | pnmdepth 255 \
      | pnmcut  1  9 1545 2155 \
      > /tmp/t-y1.pgm
    rgb3toppm /tmp/t-y0.pgm /tmp/t-y1.pgm /tmp/t-y0.pgm \
      > .check.ppm
    xv .check.ppm &

  Cropping and aligning the two sets:
  
    foreach c ( 1 0 ) 
      cat /tmp/t-x${c}.pgm \
        | pnmcut 5 5 1500 2100 \
        > n/a-x${c}.pgm
      cat /tmp/t-y${c}.pgm \
        | pnmrotate -0.185 \
        | pnmdepth 255 \
        | pnmcut 12 5 1500 2100 \
        > n/a-y${c}.pgm
      rgb3toppm n/a-x${c}.pgm n/a-y${c}.pgm n/a-x${c}.pgm \
        > .check.ppm
      xv .check.ppm
    end

  Computing the approximate transmission term:

    foreach s ( x y )
      pnmxarith -subtract n/a-${s}1.pgm n/a-${s}0.pgm \
        | pgmnorm -bvalue 000 -wvalue 50 \
        | pnmdepth 255 \
        > n/a-${s}t.pgm
    end
    rgb3toppm n/a-xt.pgm n/a-yt.pgm n/a-xt.pgm \
      > n/a-dt.ppm
    xv n/a-dt.ppm n/a-{x,y}t.pgm &
  

----------------------------------------------------------------------

  Removing the ghosts:

    ln -s ~stolfi/programs/m3-3.6/IMG/PGMRemoveGhost/$M3PLATFORM/PGMRemoveGhost
    
    set black = 0.005
    set white = 0.995
    nice -19 PGMRemoveGhost \
        -inName n/a \
        -outName n/a \
        -gamma 0.667 \
        -paperColor 1.000 \
        -blackColor ${black} \
        -whiteColor ${white} \
        -debug 213 1497 \
        -writePixels
    xv n/a-{x,y}{0,1}.pgm &
    xv n/a-{{x,y}c,tr}.pgm &
      
    cat n/a-yc.pgm \
      | pnmflip -lr \
      > n/a-yc-r.ppm

    xv n/a-*.pgm &