SHREC'18 track: Retrieval of color pattern depicted on 3D models

The aim of this SHREC'18 track is to evaluate the performance of the retrieval algorithms when the surface of the 3D models is decorated with different color patterns (e.g. circles, squares, stripes, etc). Starting from a pre-classified dataset of “null” 3D models, a number of textures with different patterns is applied to each model. The track is organized by IMATI CNR . The SHREC'18 track: Retrieval of color pattern depicted on 3D models final report will appear, after revision, in the proceedings of the EUROGRAPHICS Workshop on 3D Object Retrieval (3DOR).

Differently from the previous tracks: SHREC’13 track: Retrieval on textured 3D models, SHREC’14 track: Retrieval and classification on textured 3D models and SHREC’15 track on shape retrieval from non rigid/textured/low quality models , in this contest we only focus on the texture-based classification of the models. The surface classification will be independent of the overall surface.

Dataset, ground truth and evaluation

The dataset consists of 300 surfaces characterized by different patterns. A model may present a single or a couple of patterns. All models are oriented, connected and locally regular, triangle meshes. Starting from a set of "null" triangle meshes, a set of color patterns has been applied to the meshes using a semi-automatic procedure. The models in the dataset are randomly shuffled. A set of examples is made available here.

Each model will be used in turn as a query against the remaining part of the database. For a given query, the goal is to retrieve the most similar objects. The relevance or non-relevance of the models for a given query, i.e. the ground truth, will be established a priori, on the basis of the pattern(s) applied to that mesh. The performance of the retrieval algorithms will be evaluated using the precision-recall curves, nearest neighbor, first tier, second tier, normalized discounted cumulated gain and average dynamic recall.

Registration and other procedures
Each participant is requested to register to the track by sending an email to Elia Moscoso Thompson (email: elia.moscoso@ge.imati.cnr.it) or Silvia Biasotti (email: silvia.biasotti@ge.imati.cnr.it) with the subject "SHREC'18 track: Retrieval of color pattern depicted on 3D models". Then, an answer will be sent to each participant with the instructions to:

• Download a set of examples (PLY/OFF files), which will be available from January 2018, the 29th;
• Provide by February, 2018, the 12th the results of his/her runs, the program that generated the results (binary code, including appropriate user’s instructions if needed) and a summary of the proposed method. For each task, the results of up to 3 runs may be submitted: each run may come from a different algorithm, or from a different parameter setting.
• For each run, the output format we expect for the results is a plain ASCII file containing a similarity matrix. Entry (i,j) of the matrix is the similarity meansure value between the model i and the model j. We expect one file for each run.

Further Information

• The evaluations will be done automatically;
• the track results will be combined into a joint paper, to be published in the proceedings of the Eurographics Workshop on 3D Object Retrieval;
• the description of the track and its results will be presented at the Eurographics Workshop on 3D Object Retrieval (April 15,16, 2018).