exif-py是一个纯python实现的获取图片元数据的python库，官方下载地址：
http://exif-py.svn.sourceforge.net/viewvc/exif-py/source/EXIF.py?revision=19&view=markup

# library test/debug function (dump given files)
if __name__ == '__main__':
    import sys
    import getopt
 
    # parse command line options/arguments
    try:
        opts, args = getopt.getopt(sys.argv[1:], "hqsdt:v", ["help", "quick", "strict", "debug", "stop-tag="])
    except getopt.GetoptError:
        usage(2)
    if args == []:
        usage(2)
    detailed = True
    stop_tag = 'UNDEF'
    debug = False
    strict = False
    for o, a in opts:
        if o in ("-h", "--help"):
            usage(0)
        if o in ("-q", "--quick"):
            detailed = False
        if o in ("-t", "--stop-tag"):
            stop_tag = a
        if o in ("-s", "--strict"):
            strict = True
        if o in ("-d", "--debug"):
            debug = True
 
    # output info for each file
    for filename in args:
        try:
            file=open(filename, 'rb')
        except:
            print "'%s' is unreadable\n"%filename
            continue
        print filename + ':'
        # get the tags
        data = process_file(file, stop_tag=stop_tag, details=detailed, strict=strict, debug=debug)
        if not data:
            print 'No EXIF information found'
            continue
 
        x=data.keys()
        x.sort()
        for i in x:
            if i in ('JPEGThumbnail', 'TIFFThumbnail'):
                continue
            try:
                print '   %s (%s): %s' % \
                      (i, FIELD_TYPES[data[i].field_type][2], data[i].printable)
            except:
                print 'error', i, '"', data[i], '"'
        if 'JPEGThumbnail' in data:
            print 'File has JPEG thumbnail'
        print