;; conversion of lineremoval.c

(require-extension format)
(require-extension leptonica)

(define pix (pix-read "dave-orig.png"))
(define gray-pix (pix-threshold-to-binary pix 170))

(pix-write "dave-gray.png" gray-pix IFF-PNG)

(define rotated-pix)
(let-values (((ang conf) (pix-find-skew gray-pix)))
            (format #t "Angle: ~f Confidence: ~f~&" ang conf)
            (set! rotated-pix (pix-rotate-am-gray pix ang 255)))
(pix-write "dave-rotated.png" rotated-pix IFF-PNG)

;; locates the lines to remove
(define no-gaps-pix (pix-close-gray rotated-pix 51 1))
(pix-write "dave-no-gaps.png" no-gaps-pix IFF-PNG)

;; solidifies the lines to remove
(define eroded-pix (pix-erode-gray no-gaps-pix 51 1))
(pix-write "dave-eroded.png" eroded-pix IFF-PNG)

;; clean the background of the lines
(define thresholded-pix 
  (pix-threshold-to-value
    #f
    (pix-threshold-to-value 
      #f eroded-pix 210 255)
    200 0))
(define removed-lines-pix (pix-threshold-to-binary
                            thresholded-pix
                            210))
(pix-write "dave-background-lines.png" removed-lines-pix IFF-PNG)

;; add inverted cleaned lines to original
(pix-invert thresholded-pix thresholded-pix)
(define added-pix (pix-add-gray #f rotated-pix thresholded-pix))
(pix-write "dave-added.png" added-pix IFF-PNG)
(define filled-lines-pix (pix-open-gray added-pix 1 9))
(pix-write "dave-filled-lines.png" filled-lines-pix IFF-PNG)
(pix-combine-masked added-pix filled-lines-pix removed-lines-pix)
(pix-write "dave-result.png" added-pix IFF-PNG)