There are lot of components are avaiable for the meta data extractor from the image file.

IPTCInfo

The IPTCInfo module allows you to add/edit metadata
to your image. You can download it from here.

Reading
from iptcinfo import IPTCInfo

info = IPTCInfo('test.jpg')
print info.keywords, info.supplementalCategories, info.contacts
caption = info.data['caption/abstract']

Add/Edit

info = IPTCInfo('test.jpg')
info.data['caption/abstract'] = 'Witty caption here'
info.data['supplemental category'] = ['portrait']
info.save()
info.saveAs('test_out.jpg') # keep original safe

And also

ImageMagick

ImageMagick® is a software suite to create, edit, and compose bitmap images. It can read, convert and write images in a variety of formats (about 100) including DPX, GIF, JPEG, JPEG-2000, PDF, PhotoCD, PNG, Postscript, SVG, and TIFF. Use ImageMagick to translate, flip, mirror, rotate, scale, shear and transform images, adjust image colors, apply various special effects, or draw text, lines, polygons, ellipses and Bézier curves.

The functionality of ImageMagick is typically utilized from the command line or you can use the features from programs written in your favorite programming language. Choose from these interfaces: G2F (Ada), MagickCore (C), MagickWand (C), ChMagick (Ch), ImageMagickObject (COM+), Magick++ (C++), JMagick (Java), L-Magick (Lisp), nMagick (Neko/haXe), MagickNet (.NET), PascalMagick (Pascal), PerlMagick (Perl), MagickWand for PHP (PHP), PythonMagick (Python), RMagick (Ruby), or TclMagick (Tcl/TK). With a language interface, use ImageMagick to modify or create images automagically and dynamically.


thanks

__________________
Karpagarajan. R
Necessity is the mother of invention