解决Python图片处理模块pillow使用中出现的问题

最近爬一个电影票房的网站（url：http://58921.com/alltime），上面总票房里面其实是一张图片，那么我需要把图片识别成文字，来获取票房数据。

 

我头脑里第一想到的解决方案就是要用tesseract3，别用2，经验来说3相比2，对中文的支持更好一点。

 

然后，我开始使用pip安装一系列相关的库：

 

$ pip install Pillow
$ pip install pytesser3
$ pip install pytesseract

 

第一步，首先执行：

 

$ pip install pillow

 

出现报错：

 

Collecting pillow
  Could not fetch URL https://pypi.python.org/simple/pillow/: There was a problem confirming the ssl certificate: [SSL: TLSV1_ALERT_PROTOCOL_VERSION] tlsv1 alert protocol version (_ssl.c:661) - skipping
  Could not find a version that satisfies the requirement pillow (from versions: )
No matching distribution found for pillow

 

截图如下：

 

 

我的第一反应是加个sudo，sudo pip install pillow来安装，出现同样报错，截图如下：

 

 

其实是pip的版本低了，然后我尝试更新pip版本，使用如下命令：

 

python -m pip install --upgrade pip

 

出现报错：

 

Could not fetch URL https://pypi.python.org/simple/pip/: There was a problem confirming the ssl certificate: [SSL: TLSV1_ALERT_PROTOCOL_VERSION] tlsv1 alert protocol version (_ssl.c:661) - skipping
Requirement already up-to-date: pip in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages

 

截图如下：

 

 

还是不行！

 

那么，换一种方式更新pip，命令如下：

 

$ pip install -U pip

 

还是出现报错：

 

Could not fetch URL https://pypi.python.org/simple/pip/: There was a problem confirming the ssl certificate: [SSL: TLSV1_ALERT_PROTOCOL_VERSION] tlsv1 alert protocol version (_ssl.c:661) - skipping
Requirement already up-to-date: pip in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages

 

截图如下：

 

 

再换一种更新pip，命令如下：

 

curl https://bootstrap.pypa.io/get-pip.py | python

 

注意一下后面，如果你是python3，那么：

 

curl https://bootstrap.pypa.io/get-pip.py | python3

 

终于可以了！

 

最终解决方案参考至：

https://github.com/pypa/pip/issues/5236

 

---

 

然后安装pillow，命令如下：

 

$ pip install pillow

 

另外，建议使用pillow，PIL好多年前就停更了，现在pillow fork过来，然后一直在维护。

 

现在可以使用最新的pip批量安装上述的库了。

 

---

 

 

后来写了一个test.py，发现使用pytesseract.image_to_string()函数时，报下面的崩溃：

 

Traceback (most recent call last):
  File "/Users/baorunchen/Documents/code/repo/python/advanced/image_recognition_test.py", line 29, in <module>
    main()
  File "/Users/baorunchen/Documents/code/repo/python/advanced/image_recognition_test.py", line 26, in main
    run_log(pytesseract.image_to_string(im))
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pytesseract/pytesseract.py", line 193, in image_to_string
    return run_and_get_output(image, 'txt', lang, config, nice)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pytesseract/pytesseract.py", line 140, in run_and_get_output
    run_tesseract(**kwargs)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pytesseract/pytesseract.py", line 111, in run_tesseract
    proc = subprocess.Popen(command, stderr=subprocess.PIPE)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 390, in __init__
    errread, errwrite)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/subprocess.py", line 1024, in _execute_child
    raise child_exception
OSError: [Errno 2] No such file or directory

 

截图如下：

 

 

原因是：安装Tesseract-OCR后，其不会被默认添加至环境变量path中，已导致报错；

 

解决这个问题可参考网址：

https://stackoverflow.com/questions/35609773/oserror-errno-2-no-such-file-or-directory-using-pytesser

 

解决方案：

先需要在mac环境上安装tesseract这个库：

 

$ brew install tesseract

 

又报错了，如下：

 

touch: /usr/local/Homebrew/.git/FETCH_HEAD: Permission denied
touch: /usr/local/Homebrew/Library/Taps/caskroom/homebrew-cask/.git/FETCH_HEAD: Permission denied
touch: /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core/.git/FETCH_HEAD: Permission denied
fatal: Unable to create '/usr/local/Homebrew/.git/index.lock': Permission denied
error: could not lock config file .git/config: Permission denied
==> Downloading https://homebrew.bintray.com/bottles/tesseract-3.05.01.high_sierra.bottle.tar.gz
Already downloaded: /Users/baorunchen/Library/Caches/Homebrew/tesseract-3.05.01.high_sierra.bottle.tar.gz
==> Pouring tesseract-3.05.01.high_sierra.bottle.tar.gz
Error: The `brew link` step did not complete successfully
The formula built, but is not symlinked into /usr/local
Could not symlink share/man/man1/ambiguous_words.1
/usr/local/share/man/man1 is not writable.
 
You can try again using:
  brew link tesseract
==> Summary
🍺  /usr/local/Cellar/tesseract/3.05.01: 79 files, 38.7MB

 

截图如下：

 

 

之间我尝试更新brew，然后再brew install tesseract，没什么用；

 

$ brew update
$ sudo brew update
$ brew upgrade
$ brew cleanup
$ brew install tesseract

 

那么，按照报错提示执行下列命令：

 

$ brew link tesseract

 

出现下面报错：

 

Linking /usr/local/Cellar/tesseract/3.05.01...
Error: Could not symlink share/man/man5/unicharambigs.5
/usr/local/share/man/man5 is not writable.

 

截图如下：

 

 

尝试解决brew link失败的问题，参考网址：

https://blog.csdn.net/mingzznet/article/details/46659383

 

根据它的报错提示，注意到了"/usr/local/share/man/man5 is not writable.”

这个文件不可写，说明没权限，那么我把该文件加上当前用户的权限，执行下列命令：

$ sudo chown ${USER} /usr/local/share/man/man5

 

然后继续brew link tesseract，根据错误提示，执行相应语句，截图如下：

 

 

进行下一步，参照网址：

https://stackoverflow.com/questions/35609773/oserror-errno-2-no-such-file-or-directory-using-pytesser

 

需要在代码里添加：

 

pytesseract.pytesseract.tesseract_cmd = '<path-to-tesseract-bin>'

 

命令行输入：

 

$ which tesseract

 

之前没有brew link成功，执行上述命令的结果应该是：

 

tesseract not found

 

现在成功了，结果是：

 

/usr/local/bin/tesseract

 

那么，在代码里添加：

 

pytesseract.pytesseract.tesseract_cmd = '/usr/local/bin/tesseract'

 

然后应该就没有pytesseract.image_to_string()报错的问题了。

 

---

附代码：

#!/usr/bin/env python
# -*- coding: utf-8 -*-
 
# @version: python 2.7.13
# @author: baorunchen(runchen0518@gmail.com)
# @date: 2018/5/4
import os
 
import time
from PIL import Image
import pytesseract
 
pytesseract.pytesseract.tesseract_cmd = '/usr/local/bin/tesseract'
 
pic_path = '/Users/baorunchen/Desktop/test.png'
 
 
def run_log(log):
    print time.strftime('%Y-%m-%d %H:%M:%S', time.localtime()), '-', log
 
 
def main():
    if not os.path.exists(pic_path):
        run_log('pic not exists!')
        exit(-1)
 
    im = Image.open(pic_path)
    run_log(pytesseract.image_to_string(im))
 
if __name__ == '__main__':
    main()