.. You may want to use the usual include line. Uncomment and adjust the path. 
.. include:: ../Includes.txt


===============
eim2exifextract
===============

:Author:
      Kasper Skårhøj

:Created:
      2002-11-01T00:32:00

:Changed:
      2006-08-08T19:13:05

:Classification:
      exif service

:Author:
      Achim Eichhorn

:Email:
      AchimEichhorn@eim2.de

:Info 3:


:Info 4:


.. _metaExtract-EXIF:

metaExtract: EXIF
=================

Extension Key:  **eim2exifextract**

Copyright 2003-2005, Achim Eichhorn, <AchimEichhorn@eim2.de>

This document is published under the Open Content License

available from http://www.opencontent.org/opl.shtml

The content of this document is related to TYPO3

\- a GNU/GPL CMS/Framework available from www.typo3.com

.. _Table-of-Contents:

Table of Contents
-----------------

**metaExtract: EXIF 1**

**Introduction 1**

**Configuration 2**


.. _Introduction:

Introduction
------------

This extension provides a service of the type 'metaExtract' which gets
EXIF data from files.It is completely based on “cc\_metaexif”
developed by René Fritz, but does some changes I needed.When I used
cc\_metaexif I found some strange behaviour in my DAM installation.
Some of my customer's images weren't indexed, other images, which
seemed nearly the same in filesize, color-space and file-format where
indexed. So I had to dive into DAM source codes and found a first
hint, that some of those images had such a huge amount of meta
information stored with them, that the MySQL Database Server was out
of memory when writing meta information and the connection to the
database broke down.If you have this problem, too and want to keep all
of the meta-information, you have to reconfigure your database. You
have to increase the max\_packet\_size, which you find in my.cnf (or
whatever your MySql-configuraton file is).

When I did this, I got another error-message from typo3. This one
said, that it was impossible to update the data for the fields
”colorspace” and “meta”.

The problem with “meta” was, that the MySql Datatype, which should
take the meta information is of type “TEXT”. In my database this
datatype can only hold data up to a size of 65536 Bytes, but the meta-
information of some images was much larger.

If you come across this problem, you have two ways to solve it, the
first one, if you want to keep all meta information, is to alter the
MySql datatype of the meta field to some datatype which can take much
larger datasets.

The other possibility, which I use in this service, is to filter the
meta information and to discard informations not needed. Which data
you want to skip can be configure in the page's TSConfig of your media
sysfolder. More about this in the configuration section.

The other problem I had, was the thing with the colorspace. In EXIF
there exist (as far as I know) only two types of colorspaces, sRGB
which gets the value “1” and UNCALIBRATED with “65535”.

The database field which should take the colorspace information is of
type VARCHAR(4), the programming logic in the original service did the
following: If the meta value was “1”, it wrote “sRGB” to the database,
when the meta-value was something <> 1, it used the original value
(65535), which, interpreted as String consists of 5 characters and
what leads to a MySql error. In this service I changed the logic in a
way, that any other value than 1 leads to an empty String.

I hope for the future to get another possibility to fill in the
correct colorspace. Maybe someone with more experience with EXIF
specification has an useful hint?


.. _Configuration:

Configuration
-------------

You can configure this service in the TS-config section of your media
sysfolder.

Here is an example:

svc\_eim2exifextract\_sv1{

discard {

0 = ExtensibleMetadataPlatform

1 = ImageResourceInformation

2 = ICC\_Profile

}

skip\_too\_large = 1

db\_field\_max\_len = 65535

}

the array discard takes all EXIF tags which should not get into you
meta-data. Especially the ICC\_Profile from my customer's images were
very large, so I think it was a good idea, to skip them.

The parameter skip\_too\_large enables another mechanism, which could
be used standalone, or in combination with the discard array. If you
switch skip\_too\_large on, the algorithm collecting the exif-data
examins, if the amount of data exceeds the value of
db\_field\_max\_len. If so, it skips this field.

If you altered your meta-field in the database you have to use another
value for db\_field\_max\_len.

|img-1| eim2exifextract - 2


.. ######CUTTER_MARK_IMAGES######

.. |img-1| image:: img-1.png
.. :align: left
.. :border: 0
.. :height: 32
.. :id: Graphic1
.. :name: Graphic1
.. :vspace: 8
.. :width: 102