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authorNick White <git@njw.name>2020-02-26 16:53:14 +0000
committerNick White <git@njw.name>2020-02-26 16:53:14 +0000
commite320e069844b8f9c6e5d7e4e407cc90dff3b0f04 (patch)
treeb5e011fcd79997c89ae20f113885d483d3814db7 /cmd/splittable/main.go
parenta47b35dc44f0e770a1bb1f7b53b6aa11d6895e0b (diff)
Move things around so that integralimg is in its own repository
Diffstat (limited to 'cmd/splittable/main.go')
-rw-r--r--cmd/splittable/main.go143
1 files changed, 0 insertions, 143 deletions
diff --git a/cmd/splittable/main.go b/cmd/splittable/main.go
deleted file mode 100644
index e6df94a..0000000
--- a/cmd/splittable/main.go
+++ /dev/null
@@ -1,143 +0,0 @@
-// Copyright 2020 Nick White.
-// Use of this source code is governed by the GPLv3
-// license that can be found in the LICENSE file.
-
-package main
-
-import (
- "flag"
- "fmt"
- "image"
- "image/draw"
- _ "image/jpeg"
- "image/png"
- "log"
- "os"
-
- "rescribe.xyz/preproc/integralimg"
-)
-
-const usage = `Usage: splittable [-t thresh] [-w winsize] inimg outbase
-
-splittable is an experimental program to split a table into individual
-cells suitable for OCR. It does this by detecting lines. At present it
-just detects vertical lines and outputs images for each section
-between those lines.
-
-`
-
-// returns the proportion of the given window that is black pixels
-func proportion(i integralimg.I, x int, size int) float64 {
- w := i.GetVerticalWindow(x, size)
- return w.Proportion()
-}
-
-// findbestvline goes through every vertical line from x to x+w to
-// find the one with the lowest proportion of black pixels.
-func findbestvline(img integralimg.I, x int, w int) int {
- var bestx int
- var best float64
-
- if w == 1 {
- return x
- }
-
- right := x + w
- for ; x < right; x++ {
- prop := proportion(img, x, 1)
- if prop > best {
- best = prop
- bestx = x
- }
- }
-
- return bestx
-}
-
-// findvlines finds vertical lines, returning an array of x coordinates
-// for each line. It works by moving a window of wsize across the image,
-// marking each place where there is a higher proportion of black pixels
-// than thresh.
-func findvlines(img integralimg.I, wsize int, thresh float64) []int {
- maxx := len(img[0]) - 1
- var lines []int
-
- for x := 0; x < maxx-wsize; x+=wsize {
- if proportion(img, x, wsize) >= thresh {
- l := findbestvline(img, x, wsize)
- lines = append(lines, l)
- }
- }
-
- return lines
-}
-
-func drawsection(img *image.Gray, x1 int, x2 int) *image.Gray {
- b := img.Bounds()
- width := x2-x1
- new := image.NewGray(image.Rect(0, b.Min.Y, width, b.Max.Y))
-
- for x := 0; x < width; x++ {
- for y := b.Min.Y; y < b.Max.Y; y++ {
- new.SetGray(x, y, img.GrayAt(x1 + x, y))
- }
- }
-
- return new
-}
-
-func main() {
- flag.Usage = func() {
- fmt.Fprintf(flag.CommandLine.Output(), usage)
- flag.PrintDefaults()
- }
- thresh := flag.Float64("t", 0.85, "Threshold for the proportion of black pixels below which a window is determined to be a line. Higher means fewer lines will be found.")
- wsize := flag.Int("w", 1, "Window size for mask finding algorithm.")
- flag.Parse()
- if flag.NArg() < 2 {
- flag.Usage()
- os.Exit(1)
- }
-
- f, err := os.Open(flag.Arg(0))
- defer f.Close()
- if err != nil {
- log.Fatalf("Could not open file %s: %v\n", flag.Arg(0), err)
- }
- img, _, err := image.Decode(f)
- if err != nil {
- log.Fatalf("Could not decode image: %v\n", err)
- }
- b := img.Bounds()
- gray := image.NewGray(image.Rect(0, 0, b.Dx(), b.Dy()))
- draw.Draw(gray, b, img, b.Min, draw.Src)
-
- integral := integralimg.ToIntegralImg(gray)
- vlines := findvlines(integral, *wsize, *thresh)
-
- for i, v := range vlines {
- fmt.Printf("line detected at x=%d\n", v)
-
- if i+1 >= len(vlines) {
- break
- }
- section := drawsection(gray, v, vlines[i+1])
-
- fn := fmt.Sprintf("%s-%d.png", flag.Arg(1), v)
- f, err = os.Create(fn)
- if err != nil {
- log.Fatalf("Could not create file %s: %v\n", fn, err)
- }
- defer f.Close()
- err := png.Encode(f, section)
- if err != nil {
- log.Fatalf("Could not encode image %s: %v\n", fn, err)
- }
- }
-
-
- // TODO: find horizontal lines too
- // TODO: do rotation
- // TODO: output table cells
- // TODO: potentially send cells straight to tesseract
-}