IReadIt/src/clj/ireadit/tesseractor.clj

62 lines
2.1 KiB
Clojure

(ns ^{:doc "Meme transcriber: actual OCR interface"
:author "Simon Brooke"}
ireadit.tesseractor
(:require [clojure.java.io :as io]
[clojure.tools.logging :as log]
[ireadit.config :refer [env]])
(:import net.sourceforge.tess4j.Tesseract
java.io.File
java.net.URL
javax.imageio.ImageIO))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;
;;;; ireadit.tesseractor: actual OCR interface.
;;;;
;;;; This program is free software; you can redistribute it and/or
;;;; modify it under the terms of the GNU General Public License
;;;; as published by the Free Software Foundation; either version 2
;;;; of the License, or (at your option) any later version.
;;;;
;;;; This program is distributed in the hope that it will be useful,
;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;;; GNU General Public License for more details.
;;;;
;;;; You should have received a copy of the GNU General Public License
;;;; along with this program; if not, write to the Free Software
;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
;;;; USA.
;;;;
;;;; Copyright (C) 2019 Simon Brooke
;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Cribbed partly from https://github.com/hugoArregui/tesseract-clojure
(defn prepare-tesseract [data-path]
(let [t (Tesseract.)]
(.setDatapath t data-path)
t))
(def tesseractor (prepare-tesseract (:tess-data env)))
(defn ocr
"Perform optical charactor representation on `imgage` using the OCR engine
`t`, assuming the ISO 639-3 language `lang`, and return any text found as a
string. `image` may be supplied as a `File`, as `BufferedImage`, or as a
string, in which case it will be treated as a URL."
([image]
(ocr image tesseractor))
([image t]
(ocr image t "eng"))
([image t lang]
(let [img (if
(string? image)
(ImageIO/read (URL. image))
image)]
(.setLanguage t lang)
(.doOCR t img))))