Python读取图片属性信息的实现方法


            本文是利用Python脚本读取图片信息，有几个说明如下：

     1、没有实现错误处理

     2、没有读取所有信息，大概只有 GPS 信息、图片分辨率、图片像素、设备商、拍摄设备等

     3、简单修改后应该能实现暴力修改图片的 GPS 信息

     4、但对于本身没有 GPS 信息的图片，实现则非常复杂，需要仔细计算每个描述符的偏移量

脚本运行后，读取结果如下





脚本读取的信息

这里和 Windows 属性查看器读到的内容完全一致





图片信息1





图片信息2

源码如下







# -*- coding:utf-8 -*-

import binascii



class ParseMethod(object):

  @staticmethod

  def parse_default(f, count, offset):

    pass



  @staticmethod

  def parse_latitude(f, count, offset):

    old_pos = f.tell()

    f.seek(12 + offset)



    latitude = [0,0,0]

    for i in xrange(count):

      byte = f.read(4)

      numerator = byte.encode('hex')



      byte = f.read(4)

      denominator = byte.encode('hex')



      latitude[i] = float(int(numerator, 16)) / int(denominator, 16)





    print 'Latitude:\t%.2f %.2f\' %.2f\"' % (latitude[0], latitude[1], latitude[2])

    f.seek(old_pos)  





  @staticmethod

  def parse_longtitude(f, count, offset):

    old_pos = f.tell()

    f.seek(12 + offset)



    longtitude = [0,0,0]

    for i in xrange(count):

      byte = f.read(4)

      numerator = byte.encode('hex')



      byte = f.read(4)

      denominator = byte.encode('hex')



      longtitude[i] = float(int(numerator, 16)) / int(denominator, 16)





    print 'Longtitude:\t%.2f %.2f\' %.2f\"' % (longtitude[0], longtitude[1], longtitude[2])

    f.seek(old_pos) 



  @staticmethod

  def parse_make(f, count, offset):

    old_pos = f.tell()

    f.seek(12 + offset)

    byte = f.read(count)

    a = byte.encode('hex')

    print 'Make:\t\t' + binascii.a2b_hex(a)

    f.seek(old_pos) 



  @staticmethod

  def parse_model(f, count, offset):

    old_pos = f.tell()

    f.seek(12 + offset)

    byte = f.read(count)

    a = byte.encode('hex')

    print 'Model:\t\t' + binascii.a2b_hex(a)

    f.seek(old_pos)     



  @staticmethod

  def parse_datetime(f, count, offset):

    old_pos = f.tell()

    f.seek(12 + offset)

    byte = f.read(count)

    a = byte.encode('hex')

    print 'DateTime:\t' + binascii.a2b_hex(a)

    f.seek(old_pos)



  # rational data type, 05

  @staticmethod

  def parse_xresolution(f, count, offset):

    old_pos = f.tell()

    f.seek(12 + offset)



    byte = f.read(4)

    numerator = byte.encode('hex')

    byte = f.read(4)

    denominator = byte.encode('hex')

    xre = int(numerator, 16) / int(denominator, 16)



    print 'XResolution:\t' + str(xre) + ' dpi'

    f.seek(old_pos)



  @staticmethod

  def parse_yresolution(f, count, offset):

    old_pos = f.tell()

    f.seek(12 + offset)



    byte = f.read(4)

    numerator = byte.encode('hex')

    byte = f.read(4)

    denominator = byte.encode('hex')

    xre = int(numerator, 16) / int(denominator, 16)



    print 'YResolution:\t' + str(xre) + ' dpi'

    f.seek(old_pos)



  @staticmethod

  def parse_exif_ifd(f, count, offset):

    old_pos = f.tell()

    f.seek(12 + offset)



    byte = f.read(2)

    a = byte.encode('hex')    

    exif_ifd_number = int(a, 16)



    for i in xrange(exif_ifd_number):

      byte = f.read(2)

      tag_id = byte.encode('hex')

      #print tag_id,



      byte = f.read(2)

      type_n = byte.encode('hex')

      #print type_n,



      byte = f.read(4)

      count = byte.encode('hex')

      #print count,



      byte = f.read(4)

      value_offset = byte.encode('hex')

      #print value_offset



      value_offset = int(value_offset, 16)

      EXIF_IFD_DICT.get(tag_id, ParseMethod.parse_default)(f, count, value_offset)



    f.seek(old_pos)  



  @staticmethod

  def parse_x_pixel(f, count, value):

    print 'X Pixels:\t' + str(value)



  @staticmethod

  def parse_y_pixel(f, count, value):

    print 'y Pixels:\t' + str(value)



  @staticmethod

  def parse_gps_ifd(f, count, offset):

    old_pos = f.tell()    

    f.seek(12 + offset)

    byte = f.read(2)

    a = byte.encode('hex')  

    gps_ifd_number = int(a, 16)



    for i in xrange(gps_ifd_number):

      byte = f.read(2)

      tag_id = byte.encode('hex')

      #print tag_id,



      byte = f.read(2)

      type_n = byte.encode('hex')

      #print type_n,



      byte = f.read(4)

      count = byte.encode('hex')

      #print count,



      byte = f.read(4)

      value_offset = byte.encode('hex')

      #print value_offset



      count = int(count, 16)

      value_offset = int(value_offset, 16)

      GPS_IFD_DICT.get(tag_id, ParseMethod.parse_default)(f, count, value_offset)



    f.seek(old_pos) 



IFD_dict = {

  '010f' : ParseMethod.parse_make ,

  '0110' : ParseMethod.parse_model ,

  '0132' : ParseMethod.parse_datetime ,

  '011a' : ParseMethod.parse_xresolution ,

  '011b' : ParseMethod.parse_yresolution ,

  '8769' : ParseMethod.parse_exif_ifd ,

  '8825' : ParseMethod.parse_gps_ifd

}



EXIF_IFD_DICT = {

  'a002' : ParseMethod.parse_x_pixel ,

  'a003' : ParseMethod.parse_y_pixel

}



GPS_IFD_DICT = {

  '0002' : ParseMethod.parse_latitude ,

  '0004' : ParseMethod.parse_longtitude

}





with open('image.jpg', 'rb') as f:

  byte = f.read(2)

  a = byte.encode('hex')

  print 'SOI Marker:\t' + a



  byte = f.read(2)

  a = byte.encode('hex')

  print 'APP1 Marker:\t' + a



  byte = f.read(2)

  a = byte.encode('hex')

  print 'APP1 Length:\t' + str(int(a, 16)) + ' .Dec'



  byte = f.read(4)

  a = byte.encode('hex')

  print 'Identifier:\t' + binascii.a2b_hex(a)



  byte = f.read(2)

  a = byte.encode('hex')

  print 'Pad:\t\t' + a 



  print 



  print 'Begin to print Header.... '

  print 'APP1 Body: '



  byte = f.read(2)

  a = byte.encode('hex')

  print 'Byte Order:\t' + a  



  byte = f.read(2)

  a = byte.encode('hex')

  print '42:\t\t' + a 



  byte = f.read(4)

  a = byte.encode('hex')

  print '0th IFD Offset:\t' + a 



  print 'Finish print Header'



  print 'Begin to print 0th IFD....'

  print

  #print 'Total: ',

  byte = f.read(2)

  a = byte.encode('hex')

  interoperability_number = int(a, 16)

  #print interoperability_number





  for i in xrange(interoperability_number):

    byte = f.read(2)

    tag_id = byte.encode('hex')

    #print tag_id,



    byte = f.read(2)

    type_n = byte.encode('hex')

    #print type_n,



    byte = f.read(4)

    count = byte.encode('hex')

    #print count,



    byte = f.read(4)

    value_offset = byte.encode('hex')

    #print value_offset



    count = int(count, 16)

    value_offset = int(value_offset, 16)



    # simulate switch

    IFD_dict.get(tag_id, ParseMethod.parse_default)(f, count, value_offset)





  print

  print 'Finish print 0th IFD....'



总结

利用Python读取图片属性信息的实现方法到这就基本结束了，大家都学会了吗？希望这篇文章对大家的学习或者工作带来一定的帮助，