Initial commit

Author: RobinDavid

README.md

@@ -1,4 +1,31 @@
 Pytesser
 ========
 
-Python wrapper for the tesseract OCR engine. The module is based on OpenCV
+Python wrapper for the tesseract OCR engine. The module is based on OpenCV.
+Article : http://robindavid.comli.com/pytesser-python-wrapper-for-the-tesseract-ocr-engine/
+
+Informations
+------------
+
+There is already multiples module called pytesser, but this one is slightly different on the following point:
+
+* It implement all the features of tesseract engine it includes the choise of the language and the page segmentation mode.
+* All the module is contained in one file (the others modules I have tried are quite messy.
+* It support OpenCV, so you can directly provide an IplImage to the module.
+
+How to use it ?
+---------------
+
+There is to ways to use it. Either you give it a filename, either directly an IplImage. For a filename you can do:
+
+    import pytesser
+    txt = pytesser.image_to_string("myimage.jpg") #By default language is eng, and page seg mode auto
+
+    #To give specifify parameters:
+    txt = pytesser.image_to_string("myimage.jpg","fra",pytesser.PSM_SINGLE_WORD) #Analyse image as a single french word
+
+
+Or you can directly give it an IplImage like this:
+
+    image = cv.LoadImage("myimage.jpg")
+    txt = pytesser.iplimage_to_string(image) 

pytesser.py

@@ -0,0 +1,80 @@
+try:
+    import cv2.cv as cv
+    OPENCV_AVAILABLE = True
+except ImportError:
+    OPENCV_AVAILABLE = False
+
+from subprocess import Popen, PIPE
+import os
+
+PROG_NAME = 'tesseract'
+TEMP_IMAGE = 'tmp.bmp'
+TEMP_FILE = 'tmp'
+
+#All the PSM arguments as a variable name (avoid having to know them)
+PSM_OSD_ONLY = 0
+PSM_SEG_AND_OSD = 1
+PSM_SEG_ONLY = 2
+PSM_AUTO = 3
+PSM_SINGLE_COLUMN = 4
+PSM_VERTICAL_ALIGN = 5
+PSM_UNIFORM_BLOCK = 6
+PSM_SINGLE_LINE = 7
+PSM_SINGLE_WORD = 8
+PSM_SINGLE_WORD_CIRCLE = 9
+PSM_SINGLE_CHAR = 10
+
+class TesseractException(Exception): #Raised when tesseract does not return 0
+    pass
+
+class TesseractNotFound(Exception): #When tesseract is not found in the path
+    pass
+
+def check_path(): #Check if tesseract is in the path raise TesseractNotFound otherwise
+    for path in os.environ.get('PATH', '').split(':'):
+        filepath = os.path.join(path, PROG_NAME)
+        if os.path.exists(filepath) and not os.path.isdir(filepath):
+            return True
+    raise TesseractNotFound
+
+def process_request(input_file, output_file, lang=None, psm=None):
+    args = [PROG_NAME, input_file, output_file] #Create the arguments
+    if lang is not None:
+        args.append("-l")
+        args.append(lang)
+    if psm is not None:
+        args.append("-psm")
+        args.append(str(psm))
+    proc = Popen(args, stdout=PIPE, stderr=PIPE) #Open process
+    ret = proc.communicate() #Launch it
+    
+    code = proc.returncode 
+    if code != 0:
+        if code == 2:
+            raise TesseractException, "File not found"
+        if code == -11:
+            raise TesseractException, "Language code invalid: "+ret[1]
+        else:
+            raise TesseractException, ret[1]
+
+def iplimage_to_string(im, lang=None, psm=None):
+    if not OPENCV_AVAILABLE:
+        print "OpenCV not Available"
+        return -1
+    else:
+        cv.SaveImage(TEMP_IMAGE, im)
+        txt = image_to_string(TEMP_IMAGE, lang, psm)
+        os.remove(TEMP_IMAGE)
+        return txt
+        
+def image_to_string(file,lang=None, psm=None):
+    check_path() #Check if tesseract available in the path
+    process_request(file, TEMP_FILE, lang, psm) #Process command
+    f = open(TEMP_FILE+".txt","r") #Open back the file
+    txt = f.read()
+    os.remove(TEMP_FILE+".txt")
+    return txt
+    
+    
+if __name__ =='__main__':
+    print image_to_string("image.jpg", "fra", PSM_AUTO) #Example