added linescan example

examples/linescan_example_01.py

@@ -0,0 +1,64 @@
+import cv2 as cv
+import time
+import sys
+import numpy
+from itfbarcode import linescan
+import os
+import json
+
+jspath = 'test'
+imgpath = 'tapecameraimgs-crop'
+configpath = 'linescanconfig'
+
+bcslist = []
+failcounter = 0
+successcounter = 0
+avgtime = 0
+failedlist = []
+for fn in os.listdir(imgpath):
+    filename = os.path.join(imgpath, fn)
+    # load image data using openvc
+    img = cv.imread(filename)
+    # add red filter and convert image data into only one channel
+    vs = (img[:,:,2]/(img[:,:,0].astype('f8')+20.)).mean(axis=0)
+    t0 = time.time()
+    bcs, kw = linescan.scan(lambda a:a.value<20170, vs, {'ndigits':6}, {})
+    t1 = time.time()
+   # print ("img: %s" % (fn))
+   # print ("barcode: %s" % (bcs))
+   # print ("time: %s" % (t1 - t0))
+    bcslist.append(bcs)
+    avgtime = avgtime + t1 -t0
+    if bcs == []:
+        failcounter += 1
+        failedlist.append(fn)
+        print('failed img: %s' %(fn))
+        print('empty list[] found')
+    else:
+        realbcs = int(fn.strip('.png').split('_')[1])
+
+        bcsresult = bcs[0]
+        #if realbcs - 26 or realbcs - 25 or realbcs - 27 == bcsresult.value:
+        #if 24 or 25 or 23 == 25
+        #if 24 or 25 or False 
+        # checking if the barcode read result is correct, the real barcode of the middle one out of 4 that in one image was at the end of the image name and often have a offset of 26, since it might read any of the 4 barcodes so using all 24, 25, 26 and 27 to check.
+        if abs(bcsresult.value - realbcs) in (24, 25, 26, 27):
+
+            successcounter += 1
+        else:
+            print('barcode read as: %s' %(bcs,))
+            print('real barcode: %s' %(realbcs))
+   #  print(len(bcslist))
+print(bcslist)
+print(failcounter)
+print(successcounter)
+print('fail ratio %s' %(float(failcounter)/len(bcslist)))
+print(avgtime/len(bcslist))
+print(failedlist)
+    # save the result to json files if needed
+    # config = {}
+    # config['img'] = fn
+    # config['barcode'] = bcs
+    # config['time'] = t1 - t0
+    # with open(os.path.join(configpath, fn[:-5] +'.json'), 'w') as jfile:
+        # json.dump(config, jfile)