使用PYTHON PIL从Captcha Image中删除背景噪声线
发布时间:2020-12-20 13:33:22 所属栏目:Python 来源:网络整理
导读:我有一个处理过的验证码图像(放大)看起来像: 如您所见,“TEXT”的字体大小比Noisy Lines的宽度略大. 所以我需要一个算法或代码来从这个图像中删除嘈杂的线条. 在Python PIL库和下面提到的斩波算法的帮助下,我得不到OCR可以轻松读取的输出图像. 这是我尝试过
我有一个处理过的验证码图像(放大)看起来像:
如您所见,“TEXT”的字体大小比Noisy Lines的宽度略大. 在Python PIL库和下面提到的斩波算法的帮助下,我得不到OCR可以轻松读取的输出图像. 这是我尝试过的Python代码: import PIL.Image import sys # python chop.py [chop-factor] [in-file] [out-file] chop = int(sys.argv[1]) image = PIL.Image.open(sys.argv[2]).convert('1') width,height = image.size data = image.load() # Iterate through the rows. for y in range(height): for x in range(width): # Make sure we're on a dark pixel. if data[x,y] > 128: continue # Keep a total of non-white contiguous pixels. total = 0 # Check a sequence ranging from x to image.width. for c in range(x,width): # If the pixel is dark,add it to the total. if data[c,y] < 128: total += 1 # If the pixel is light,stop the sequence. else: break # If the total is less than the chop,replace everything with white. if total <= chop: for c in range(total): data[x + c,y] = 255 # Skip this sequence we just altered. x += total # Iterate through the columns. for x in range(width): for y in range(height): # Make sure we're on a dark pixel. if data[x,y] > 128: continue # Keep a total of non-white contiguous pixels. total = 0 # Check a sequence ranging from y to image.height. for c in range(y,height): # If the pixel is dark,add it to the total. if data[x,c] < 128: total += 1 # If the pixel is light,replace everything with white. if total <= chop: for c in range(total): data[x,y + c] = 255 # Skip this sequence we just altered. y += total image.save(sys.argv[3]) 因此,基本上我想知道一个更好的算法/代码来摆脱噪音,从而能够使图像可以被OCR(Tesseract或pytesser)读取. 解决方法
要快速摆脱大多数线条,您可以将两个或更少相邻黑色像素的所有黑色像素变为白色.这应该可以修复杂散线.然后,当你有很多“块”时,你可以删除较小的块.
这是假设样本图像已被放大,并且线仅为一个像素宽. (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |