OT EXIF libraray

Rails
1

Hi-

this is slightly off topic, but is anyone aware of a WORKING ruby
library that reads EXIF data from JPEG files?
It has to run on both Windows and *nix, so wrappers around unix libs
won’t do.

So far I tried rexif, ruby-exif (both throwing exceptions when presented
with a JPEG) and RMagick (at least able to get the date
from EXIF, however it adds a ‘.’ at the end for whatever reason plus
unable to read GPS info from EXIF).

libexif and wrappers around gtk seem problematic in the windows
environment.

What’s everbody else using?

thanks for your help,

-markus

2

Doesn’t Magick#get_exif_by_entry give you what you need?

From the documentation:

image.get_exif_by_entry(‘Make’) => [[“Make”, “Canon”]]

I know you’re looking for GPS, but perhaps you should try
get_exif_by_number
to find that.

See:

http://www.simplesystems.org/RMagick/doc/image2.html#get_exif_by_entry

HTH

View this message in context:
http://www.nabble.com/OT-EXIF-libraray-t1829170.html#a4997839
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3

Hi-

-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of s.ross
Sent: Thursday, June 22, 2006 7:24 PM
To: [email protected]
Subject: Re: [Rails] OT EXIF libraray

Doesn’t Magick#get_exif_by_entry give you what you need?

unfortunately not.

From the documentation:

image.get_exif_by_entry(‘Make’) => [[“Make”, “Canon”]]

Well
image.get_exif_by_entry(‘DateTime’) => [[“DateTime”, “2002:07:19
13:28:10.”]]

which is wrong in the first place, as it should be “2002:07:19 13:28:10”
(no . at the end). This would be easy enough to work
around, but might as well be a problem with the RMagick/ImageMagick
version.

Unfortunately GPSInfo is stored in its own IFD and a
get_exif_by_entry(‘GPSInfo’) just gives you the offset to that IFD.
Looking for
the tag number won’t help for the same reason. The API seems to lack a
way to specify the IFD you want to get the entry from.

Anyway, thanks for your help.

-markus