====== "Eternal" GREC Arc Segmentation Contest ======

At the GREC 2007 Workshop it was discussed to make the Arc Segmentation contest
an ongoing contest, i.e. we will allow submissions of results at any point in
time. (Eventually, we might have to switch to new and more test images.) The
results of all submissions are shown in the following table. If you have
results you would like to include, please send an email including your results
to [[http://www.dfki.uni-kl.de/~shafait/|Faisal Shafait]]. (We prefer results in image format - see
below - but VEC format is also acceptable.)

| Method | submitted by | submitted on || total overs. | total unders. | overs. comps | unders. comps | missed comps | false alarms |
| Liu Wenyin | Liu Wenyin       | 10-SEP-2007 ||  20 |  8 |  12 |  6 |  1 |  98 |
| Scan2CAD   | Hasan Al-Khaffaf | 09-OCT-2007 ||  72 |  9 |  48 |  7 |  4 |  64 | 
| VPStudio   | Hasan Al-Khaffaf | 09-OCT-2007 ||  55 |  4 |  49 |  3 |  3 |  64 | 
| Vectory    | Hasan Al-Khaffaf | 10-OCT-2007 ||  54 |  9 |  43 |  9 |  9 |   0 |

The VEC-files for the commercial systems were supplied with a constant line width of one pixel for all the arcs. To see the influence of this choice, we re-ran the evaluation using a constant line width of 10 pixels for all systems. The following table shows the results.

| Method | submitted by | submitted on || total overs. | total unders. | overs. comps | unders. comps | missed comps | false alarms |
| Liu Wenyin | Liu Wenyin       | 10-SEP-2007 ||  17 |   9 |   8 |  6 |  1 |  98 |
| Scan2CAD   | Hasan Al-Khaffaf | 09-OCT-2007 ||  36 |  10 |  20 |  6 |  4 |  66 | 
| VPStudio   | Hasan Al-Khaffaf | 09-OCT-2007 ||   7 |   5 |   7 |  4 |  3 |  62 | 
| Vectory    | Hasan Al-Khaffaf | 10-OCT-2007 ||  35 |  13 |  26 |  9 |  8 |   1 |

We have also prepared a [[arcseg-discussion|discussion page]] for the results
and procedure.
 
What follows is the original page for the GREC 2007 Workshop contest, which
also explains the evaluation and links to the data and web services. 

====== GREC 2007 Arc Segmentation Contest ======

IUPR will be organizing the GREC 2007 Arc Segmentation Contest. As in past
years, there will be a competition regarding the detection of arcs in digital
images held at the Graphics Recognition Workshop GREC
([[http://www.cs.cityu.edu.hk/%7Eliuwy/ArcContest/ArcSegContest.htm|see the
homepage of the GREC 2005 contest and its results]]).


===== Important Dates =====

  * 2007-03-22 web-site and examples on-line
  * 2007-06-27 conversion web-services and training images available
  * 2007-08-27 **test images available**
  * 2007-09-03 **submission of test results** (by email to [[keysers@iupr.net|Daniel Keysers]]) **Extension:** the deadline has been extended, please send [[keysers@iupr.net|me]] an email if you would like to participate.

===== Training Images =====

Here is a tar-gz-file with five scanned images (in pbm format) and the corresponding arc ground truth (in ppm format): {{arcseg2007:train.tar.gz}}

Here is a zip-file with five scanned images (in tif format, g4-compression) and the corresponding arc ground truth (in tif format, flate compression): {{arcseg2007:train.zip}}

===== Test Images =====

Here is a tar-gz-file with five scanned images (in pbm format): {{arcseg2007:test.tar.gz}}

Here is a zip-file with five scanned images (in tif format, g4-compression): {{arcseg2007:test.zip}}


===== Evaluation Web-Service =====

The web-service for evaluation of results is now available at [[http://demo.iupr.org/segeval/|http://demo.iupr.org/segeval/]].


===== VEC-format Conversion Web-Service =====

The web-service for conversion of results from VEC-format to the color-based format is now available at [[http://demo.iupr.org/vec2img/|http://demo.iupr.org/vec2img/]].

Note: the VEC-file may only contain lines that describe arcs or circles (starting with 'A' or 'C', respectively).


===== Representation and Evaluation of Arc Segmentation =====

The competition will be using a color-based evaluation method for page segmentation. The foreground pixels corresponding to each arc will be assigned a unique color. This results in a color-coded representation of image segmentation. The segmented image thus obtained will be compared to the ground-truth image using bipartite graph matching. Details of this representation and evaluation are described in this paper [[http://pubs.iupr.org/#icpr06_fs|here]]. Two example images with their color-coded segmentation representations are shown in the Figure below. 

|{{photos:grec-arcseg-example6.png?300 | Original Image}}|{{photos:grec-arcseg-example6_seg.png?300| Segmented Image}}|
|{{photos:grec-arcseg-example8.png?300 | Original Image}}|{{photos:grec-arcseg-example8_seg.png?300| Segmented Image}}|

Note that the assignment of colors to arcs is arbitrary, so you can choose any colors for representing different arcs. However, three special color values are recognized:

**0xFFFFFF** page background

**0x000000** un-classified page foreground

**0xFFFF00** pixels belonging to more than one arc


If you have any questions, please contact [[http://www.dfki.uni-kl.de/~shafait/|Faisal Shafait]].