Question

当我阅读多页的Tiff图像时，该图像是15页，并且是白色背景上的黑色字母/单词的文档，PyTesseract在我遍历页面并进行转换的步骤时抛出“ OSError：-9”错误串起来。

我将pytesseract包与pyocr.builders一起使用。单个页面似乎可以正常工作，但是我相信当图像不在RGB中时，程序会转换为RGB。

img = Image.open(r'\users\ai\text.tiff')
img.load()
txt = ""
for frame in range(0, img.n_frames):
    img.seek(frame)
    txt += tool.image_to_string(img,builder=pyocr.builders.TextBuilder())

预期的输出是jupyter窗口中显示的全部15页。

错误消息

---------------------------------------------------------------------------
OSError                                   Traceback (most recent call last)
<ipython-input-17-e59bdf3b773c> in <module>
      2 for frame in range(0, img.n_frames):
      3     img.seek(frame)
----> 4     txt += tool.image_to_string(img,builder=pyocr.builders.TextBuilder())
      5 

~\AppData\Local\Continuum\anaconda3\lib\site-packages\pyocr\tesseract.py in image_to_string(image, lang, builder)
    357     with tempfile.TemporaryDirectory() as tmpdir:
    358         if image.mode != "RGB":
--> 359             image = image.convert("RGB")
    360         image.save(os.path.join(tmpdir, "input.bmp"))
    361         (status, errors) = run_tesseract("input.bmp", "output", cwd=tmpdir,

~\AppData\Local\Continuum\anaconda3\lib\site-packages\PIL\Image.py in convert(self, mode, matrix, dither, palette, colors)
    932         """
    933 
--> 934         self.load()
    935 
    936         if not mode and self.mode == "P":

~\AppData\Local\Continuum\anaconda3\lib\site-packages\PIL\TiffImagePlugin.py in load(self)
   1097     def load(self):
   1098         if self.use_load_libtiff:
-> 1099             return self._load_libtiff()
   1100         return super(TiffImageFile, self).load()
   1101 

~\AppData\Local\Continuum\anaconda3\lib\site-packages\PIL\TiffImagePlugin.py in _load_libtiff(self)
   1189 
   1190         if err < 0:
-> 1191             raise IOError(err)
   1192 
   1193         return Image.Image.load(self)

OSError: -9

Answer 1

对于这样的问题，由于遗漏了一些代码，因此您应该提供Minimum Reproducible Example。另外，您应该提供测试图像。但是，对于此示例，您无法附加多页TIFF，因此链接到其中将是不错的选择。

我能够从this test image中找到this question。这是10页的TIFF。

这是使用pyocr的解决方案：

from PIL import Image

import pytesseract
import pyocr
import pyocr.builders

tools = pyocr.get_available_tools()
tool = tools[0]

# pytesseract.pytesseract.tesseract_cmd = 'C:\\Program Files (x86)\\Tesseract-OCR\\tesseract.exe'


image = Image.open('multipage_tiff_example.tif')

config = ("--psm 6")

txt = ''
for frame in range(image.n_frames):
    image.seek(frame)
    txt = tool.image_to_string(image, builder=pyocr.builders.TextBuilder())
    print(txt)

这是使用pytesseract的解决方案：

from PIL import Image
import pytesseract

# pytesseract.pytesseract.tesseract_cmd = 'C:\\Program Files (x86)\\Tesseract-OCR\\tesseract.exe'

image = Image.open('multipage_tiff_example.tif')

config = ("--psm 6")

txt = ''
for frame in range(image.n_frames):
    image.seek(frame)
    txt += pytesseract.image_to_string(image, config = config, lang='eng') + '\n'

print(txt)

都给出以下输出：

Multipage
TIFF
Example
Page 1
Multipage
TIFF
Example
Page 2
Multipage
TIFF
Example
Page 3
Multipage
TIFF
Example
Page 4
Multipage
TIFF
Example
Page5
Multipage
TIFF
Example
Page 6
Multipage
TIFF
Example
Page /
Multipage
TIFF
Example
Page 8
Multipage
TIFF
Example
Page 9
Multipage
TIFF

Example

Page 10

多页Tiff图像的PyTesseract错误

1 个答案: