=Paper= {{Paper |id=Vol-1173/CLEF2007wn-ImageCLEF-WilhelmEt2007 |storemode=property |title=Experiments for the ImageCLEF 2007 Photographic Retrieval Task |pdfUrl=https://ceur-ws.org/Vol-1173/CLEF2007wn-ImageCLEF-WilhelmEt2007.pdf |volume=Vol-1173 |dblpUrl=https://dblp.org/rec/conf/clef/WilhelmKE07 }} ==Experiments for the ImageCLEF 2007 Photographic Retrieval Task== https://ceur-ws.org/Vol-1173/CLEF2007wn-ImageCLEF-WilhelmEt2007.pdf
    Experiments for the ImageCLEF 2007 Photographic
                      Retrieval Task
                            Thomas Wilhelm, Jens Kürsten, Maximilian Eibl
                                   Chemnitz, University of Technology
                         Faculty of Computer Science, Chair Media Informatics
                                          Straße der Nationen 62
                                        09111 Chemnitz, Germany
                   [ thomas.wilhelm | jens.kuersten | eibl ] at informatik.tu-chemnitz.de


                                                 Abstract
     This article describes the configuration of the experiments that we submitted for the ImageCLEF
     Photographic Retrieval Task. We used a redesigned version of our last years retrieval system
     prototype (see [1] for details). The translation of the topics for our cross-lingual experiments
     was realized with a plug-in to access the Google Translate [2] service. We used thesauri from
     OpenOffice [3] to expand the queries for better retrieval performance. This year, we submitted
     11 runs, whereof only one was completely automatic. In all our experiments mixed modality
     was applied, i.e. we used text retrieval and content-based image retrieval for re-ranking. The
     evaluation results show that most of our experiments achieved very strong retrieval performance.

Categories and Subject Descriptors
H.3 [Information Storage and Retrieval]: H.3.1 Content Analysis and Indexing; H.3.3 Information Search
and Retrieval

Keywords
Evaluation, Cross-Language Information Retrieval, Content-based Image Retrieval, Query Expansion, Ex-
perimentation


1    Introduction and outline
This year, we used a redesigned version of our retrieval prototype from 2006 to participate in the ImageCLEF
Photographic Retrieval Task. The general description of the task is given in [4]. To overcome the challenging
task thesauri were used for query expansion. We hoped to balance the reduced amount of textual annotations
with this approach. Our experiments were based on text retrieval and were optimized with content-based
image retrieval.
The outline of the paper is as follows. Section 2 describes the general setup of our system. The individual
configurations of our submitted experiments are shown in section 3. In sections 4 and 5 we summarize the
results and sum up our observations.


2    Experimental setup
The approach we used for the ImageCLEF Photographic Retrieval Task is as follows. We decided to use
an automatic query expansion approach to balance the reduced amount of textual annotations in the data
collection. We used thesauri from OpenOffice [3] by applying a threshold technique to obtain a number
of terms for each query. The baseline of all our experiments was a classic text retrieval run. In a second
step the results of the text retrieval were re-ranked based on image content descriptors. We applied the
MPEG-7 descriptors EdgeHistogram and ScalableColor from the Caliph and Emir project [5] that were
calculated from the example image of each topic. Finally, we used a manual feedback strategy to enhance
retrieval performance in all our setups except the baseline run. The feedback strategy was to assess a certain
number of the top documents and to apply a feedback algorithm that uses the annotations from the relevant
documents.


3     Configuration of submitted runs
The detailed setup of our experiments are presented in the following subsections.

3.1    Monolingual
We submitted 5 monolingual experiments in total, whereof one was the completely automatic baseline run
(first row in table 1).


                            Table 1: Configuration of monolingual experiments
                             identifier         language # images for FB
                             cut-EN2EN          EN         0
                             cut-EN2EN-F20 EN              20
                             cut-EN2EN-F50 EN              50
                             cut-ES2ES          ES         20
                             cut-DE2DE          DE         20


3.2    Cross-lingual
We also submitted cross-language experiments for all target collections. The translation was realized with
a plug-in that is capable to access the Google Translate [2] service. We also used the thesauri based query
expansion approach that was mentioned before. Table 2 shows the setup of the individual cross-language
runs.

                          Table 2: Configuration of cross-lingual experiments
               identifier        query language        target language # images for FB
               cut-EN2ES-F20     English               Spanish           20
               cut-ZHS2EN-F20 Chinese, simplified English                20
               cut-DE2EN-F20     German                English           20
               cut-IT2EN-F20     Italian               English           20
               cut-FR2EN-F20     French                English           20
               cut-FR2DE-F20     French                German            20


4     Results
The results of our submitted runs are summarized in table 3. It can be seen that our monolingual english
experiment performed best. Furthermore, one can observe that monolingual retrieval performance for english
and spanish annotations is very good, while monolingual retrieval on german annotations is quite bad in
comparison. Another interesting observation is the result for the cross-lingual experiment with english topics
on spanish annotations, which performs better than all cross-lingual runs on the english annotations.
                                Table 3: Results for submitted experiments
                                identifier          MAP      P20     Rank
                                cut-EN2EN-F50       0.3175 0.4592 1
                                cut-EN2EN-F20       0.2846 0.4025 5
                                cut-ES2ES           0.2772 0.3708 12
                                cut-EN2ES-F20       0.2770 0.3767 13
                                cut-ZHS2EN-F20 0.2690 0.4042 19
                                cut-DE2EN-F20       0.2565 0.3650 22
                                cut-IT2EN-F20       0.2495 0.3633 28
                                cut-FR2EN-F20       0.2432 0.3583 31
                                cut-DE2DE           0.1991 0.2992 40
                                cut-FR2DE-F20       0.1640 0.2367 100
                                cut-EN2EN           0.1515 0.2383 142


5    Conclusion
Our experiments showed that the manual feedback strategy is a promising approach for this year’s ImageCLEF
Photographic Retrieval Task. But also the combination of text retrieval and well-known content-based image
descriptors as well as the application of thesauri based query expansion in this domain - with a small amount
of textual metadata - was important for good retrieval performance.


References
[1] Wilhelm, T. & Eibl, M. (2006). ImageCLEF 2006 Experiments at the Chemnitz Technical University. In
    Working Notes for the CLEF 2006 Workshop, 20-22 September, Alicante, Spain. Retrieved August 17,
    2007, from CLEF Web site:
    http://www.clef-campaign.org/2006/working_notes/workingnotes2006/wilhelmCLEF2006l.pdf
[2] Google (2007). Google Translate BETA. Retrieved August 17, 2007, from Google Web site:
    http://www.google.com/translate_t
[3] OpenOffice (2007). OpenOffice. Retrieved August 17, 2007, from OpenOffice Web site:
    http://www.openoffice.org/

[4] Grubinger, M. & Cloug, P. & Hanburry, A. & Müller, H. (2007). Overview of the ImageCLEFphoto
    2007 Photographic Retrieval Task. In Working Notes for the CLEF 2007 Workshop, 19-21 September,
    Budapest, Hungary. To appear.
[5] Lux, M. (2004-2007). Calpih & Emir. Retrieved August 17, 2007, from SemanticMetadata Web site:
    http://www.semanticmetadata.net/