diff options
Diffstat (limited to 'src/pyexiv2.py')
| -rw-r--r-- | src/pyexiv2.py | 122 |
1 files changed, 52 insertions, 70 deletions
diff --git a/src/pyexiv2.py b/src/pyexiv2.py index 846684e..0e2ebb4 100644 --- a/src/pyexiv2.py +++ b/src/pyexiv2.py @@ -28,6 +28,7 @@ # 30-Dec-06, Olivier Tilloy: documentation using doc strings # 08-Jan-07, Olivier Tilloy: improved the datetime conversion algo # 10-Jan-07, Olivier Tilloy: added method getIptcTagValue +# 17-Jan-07, Olivier Tilloy: improved date and time conversion algos # # ****************************************************************************** @@ -130,44 +131,41 @@ def StringToDate(string): Try to convert a string containing a date to a date object. Try to convert a string containing a date to the corresponding date object. - The conversion is done by trying several patterns for regular expression - matching. - If no pattern matches, the string is returned unchanged. + The conversion is done by matching a regular expression. + If the pattern does not match, the string is returned unchanged. Keyword arguments: string -- the string potentially containing a date """ - # Possible formats to try # According to the IPTC specification - # [http://www.iptc.org/std/IIM/4.1/specification/IIMV4.1.pdf], the only - # accepted format for a string field representing a date is - # '%Y%m%d', but it seems that others formats can be found in the wild, so - # this list could be extended to include new exotic formats. - formats = ['%Y%m%d', '%Y-%m-%d'] - - for format in formats: - try: - t = time.strptime(string, format) - return datetime.date(*t[:3]) - except ValueError: - # the tested format does not match, do nothing - pass - - # none of the tested formats matched, return the original string unchanged - return string + # [http://www.iptc.org/std/IIM/4.1/specification/IIMV4.1.pdf], the format + # for a string field representing a date is '%Y%m%d'. + # However, the string returned by exiv2 using method DateValue::toString() + # is formatted using pattern '%Y-%m-%d'. + format = '%Y-%m-%d' + try: + t = time.strptime(string, format) + return datetime.date(*t[:3]) + except ValueError: + # the tested format does not match, do nothing + return string def StringToTime(string): """ Try to convert a string containing a time to a time object. Try to convert a string containing a time to the corresponding time object. - The conversion is done by trying several patterns for regular expression - matching. - If no pattern matches, the string is returned unchanged. + The conversion is done by matching a regular expression. + If the pattern does not match, the string is returned unchanged. Keyword arguments: string -- the string potentially containing a time """ + # According to the IPTC specification + # [http://www.iptc.org/std/IIM/4.1/specification/IIMV4.1.pdf], the format + # for a string field representing a time is '%H%M%S±%H%M'. + # However, the string returned by exiv2 using method TimeValue::toString() + # is formatted using pattern '%H:%M:%S±%H:%M'. # TODO: for now, and if the function manages to correctly parse a time, # the returned result is a list of 3 elements @@ -177,53 +175,37 @@ def StringToTime(string): # (http://docs.python.org/lib/datetime-tzinfo.html). # A minimal tzinfo concrete subclass must be implemented... - # First pass: process the offset (value added to the local time to arrive - # at UTC) separately. - p = string.rfind('+') - if p != -1: - # the timezone is west of the Prime Meridian (Greenwich) - localtime = string[:p] - offset = string[(p + 1):] - offsetSign = '+' - else: - p = string.rfind('-') - if p != -1: - # the timezone is east of the Prime Meridian - localtime = string[:p] - offset = string[(p + 1):] - offsetSign = '-' - else: - # no offset found, assume it is nil - localtime = string - offset = '0000' - offsetSign = '+' - if len(offset) != 4: - # the format of the offset is unknown, assume it is nil - offsetTime = datetime.time(0, 0) - else: - offsetTime = datetime.time(int(offset[:2]), int(offset[2:])) - - # Second pass: process the local time. - - # Possible formats to try - # According to the IPTC specification - # [http://www.iptc.org/std/IIM/4.1/specification/IIMV4.1.pdf], the only - # accepted format for a string field representing a time is - # '%H%M%S' (not taking into account the offset since it has been already - # processed), but it seems that others formats can be found in the wild, - # so this list could be extended to include new exotic formats. - formats = ['%H%M%S', '%H:%M:%S'] - - for format in formats: - try: - t = time.strptime(localtime, format) - return datetime.time(*t[3:6]), offsetSign, offsetTime - except ValueError: - # the tested format does not match, do nothing - pass - - # none of the tested formats matched, return the original string unchanged - return string + if len(string) != 14: + # the string is not correctly formatted, do nothing + return string + + if (string[2] != ':') or (string[5] != ':') or (string[11] != ':'): + # the string is not correctly formatted, do nothing + return string + + offsetSign = string[8] + if (offsetSign != '+') and (offsetSign != '-'): + # the string is not correctly formatted, do nothing + return string + + try: + hours = int(string[:2]) + minutes = int(string[3:5]) + seconds = int(string[6:8]) + offsetHours = int(string[9:11]) + offsetMinutes = int(string[12:]) + except ValueError: + # the string is not correctly formatted, do nothing + return string + + try: + localTime = datetime.time(hours, minutes, seconds) + offsetTime = datetime.time(offsetHours, offsetMinutes) + except ValueError: + # the values are out of range, do nothing + return string + + return localTime, offsetSign, offsetTime class Image(libpyexiv2.Image): |