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No Support => General discussion (no support!) => Topic started by: Dannisk on August 27, 2004, 05:14:06 pm

Title: Keeping the EXIF information when using the web image tools
Post by: Dannisk on August 27, 2004, 05:14:06 pm
Hi All,

I notice that the EXIF information is not kept (in the image) when I use the web image tool (croping and rotating tool) is this consider as a feature or his someone already working on that. I'm asking 'cause I know that you are working on having more EXIF info in the database and the easy way to update this information would be to flush the exif table and regenerate the exif from the image already stored. But if the image have been modified with the image tool we'll be left with missing EXIF information.

Thanks for any info.
Title: Re: Keeping the EXIF information when using the web image tools
Post by: Joachim Müller on August 27, 2004, 10:03:23 pm
the PicEditor uses your image library (usually GD), which doesn't keep Exif info - it's being stripped from the pic (as it's actually a new pic, with the old one deleted and the new one saved in it's place). The only solution would be a tool that can write exif info to a file (we currently don't have such a tool available). I'd appreciate your comments on this, not sure what else to do.
I recommend rotating on the client before uploading anyway.

Joachim
Title: Re: Keeping the EXIF information when using the web image tools
Post by: Dannisk on August 28, 2004, 01:21:15 am
Humm... so the solution would be to read the exif data, make the modification (rotation/croping) and then write back the exif data. Some information from the exif will also need to be changed to represent the changes like the new width and height and maybe a comment saying it has been altered by some tool (ex: Coppermine Picture Web Tools ;)).

As I understood the Exifier 1.4 (http://www.offsky.com/software/exif/) will be used for cpg1.4, the problem is that this lib doesn't write exif data, it only reads it. I did a bit or searching and I found another tool that seams more complete : The PHP JPEG Metadata Toolkit (http://www.ozhiker.com/electronics/pjmt/). That lib read more than 450 popular digital cameras and it also write EXIF data. I didn't test the difference between these two libs (read performance, amount of data available, etc.) but before I do, I'm currently checking with the author to see if it's feasible 'cause it seams that there's some problem writing MakerNotes.

I'll get back on this subject once I have an answer from the author or if I have time to make my own tests.
Title: Re: Keeping the EXIF information when using the web image tools
Post by: Tarique Sani on August 28, 2004, 05:46:46 am
The PHP JPEG Metadata Toolkit does look very promising and if it returns the metadata in an array - it can be a "drop in" replacement for Exifier. Yes even I noticed that writing back Maker notes is a problem