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Publications of Christopher Tralie    :chronological  alphabetical  combined listing:

%% Papers Published   
@article{fds330205,
   Author = {Tralie, CJ and Smith, A and Borggren, N and Hineman, J and Bendich, P and Zulch, P and Harer, J},
   Title = {Geometric cross-modal comparison of heterogeneous sensor
             data},
   Journal = {2018 Ieee Aerospace Conference},
   Publisher = {IEEE},
   Year = {2018},
   Month = {March},
   url = {http://dx.doi.org/10.1109/aero.2018.8396789},
   Abstract = {In this work, we address the problem of cross-modal
             comparison of aerial data streams. A variety of simulated
             automobile trajectories are sensed using two different
             modalities: full-motion video, and radio-frequency (RF)
             signals received by detectors at various locations. The
             information represented by the two modalities is compared
             using self-similarity matrices (SSMs) corresponding to
             time-ordered point clouds in feature spaces of each of these
             data sources; we note that these feature spaces can be of
             entirely different scale and dimensionality. Several metrics
             for comparing SSMs are explored, including a cutting-edge
             time-warping technique that can simultaneously handle local
             time warping and partial matches, while also controlling for
             the change in geometry between feature spaces of the two
             modalities. We note that this technique is quite general,
             and does not depend on the choice of modalities. In this
             particular setting, we demonstrate that the cross-modal
             distance between SSMs corresponding to the same trajectory
             type is smaller than the cross-modal distance between SSMs
             corresponding to distinct trajectory types, and we formalize
             this observation via precision-recall metrics in
             experiments. Finally, we comment on promising implications
             of these ideas for future integration into
             multiple-hypothesis tracking systems.},
   Doi = {10.1109/aero.2018.8396789},
   Key = {fds330205}
}

@article{fds330397,
   Author = {Tralie, CJ and Perea, JA},
   Title = {(Quasi)Periodicity Quantification in Video Data, Using
             Topology},
   Journal = {Siam Journal on Imaging Sciences},
   Volume = {11},
   Number = {2},
   Pages = {1049-1077},
   Publisher = {Society for Industrial & Applied Mathematics
             (SIAM)},
   Year = {2018},
   Month = {January},
   url = {http://dx.doi.org/10.1137/17m1150736},
   Abstract = {This work introduces a novel framework for quantifying the
             presence and strength of recurrent dynamics in video data.
             Specifically, we provide continuous measures of periodicity
             (perfect repetition) and quasiperiodicity (superposition of
             periodic modes with non-commensurate periods), in a way
             which does not require segmentation, training, object
             tracking or 1-dimensional surrogate signals. Our methodology
             operates directly on video data. The approach combines ideas
             from nonlinear time series analysis (delay embeddings) and
             computational topology (persistent homology), by translating
             the problem of finding recurrent dynamics in video data,
             into the problem of determining the circularity or
             toroidality of an associated geometric space. Through
             extensive testing, we show the robustness of our scores with
             respect to several noise models/levels; we show that our
             periodicity score is superior to other methods when compared
             to human-generated periodicity rankings; and furthermore, we
             show that our quasiperiodicity score clearly indicates the
             presence of biphonation in videos of vibrating vocal
             folds.},
   Doi = {10.1137/17m1150736},
   Key = {fds330397}
}

@article{fds330395,
   Author = {Tralie, CJ},
   Title = {Self-Similarity Based Time Warping},
   Year = {2017},
   Month = {November},
   Abstract = {In this work, we explore the problem of aligning two
             time-ordered point clouds which are spatially transformed
             and re-parameterized versions of each other. This has a
             diverse array of applications such as cross modal time
             series synchronization (e.g. MOCAP to video) and alignment
             of discretized curves in images. Most other works that
             address this problem attempt to jointly uncover a spatial
             alignment and correspondences between the two point clouds,
             or to derive local invariants to spatial transformations
             such as curvature before computing correspondences. By
             contrast, we sidestep spatial alignment completely by using
             self-similarity matrices (SSMs) as a proxy to the
             time-ordered point clouds, since self-similarity matrices
             are blind to isometries and respect global geometry. Our
             algorithm, dubbed "Isometry Blind Dynamic Time Warping"
             (IBDTW), is simple and general, and we show that its
             associated dissimilarity measure lower bounds the L1
             Gromov-Hausdorff distance between the two point sets when
             restricted to warping paths. We also present a local,
             partial alignment extension of IBDTW based on the Smith
             Waterman algorithm. This eliminates the need for tedious
             manual cropping of time series, which is ordinarily
             necessary for global alignment algorithms to function
             properly.},
   Key = {fds330395}
}

@article{fds330396,
   Author = {Tralie, C},
   Title = {Moebius Beats: The Twisted Spaces of Sliding Window Audio
             Novelty Functions with Rhythmic Subdivisions},
   Year = {2017},
   Month = {November},
   Abstract = {In this work, we show that the sliding window embeddings of
             certain audio novelty functions (ANFs) representing songs
             with rhythmic subdivisions concentrate on the boundary of
             non-orientable surfaces such as the Moebius strip. This
             insight provides a radically different topological approach
             to classifying types of rhythm hierarchies. In particular,
             we use tools from topological data analysis (TDA) to detect
             subdivisions, and we use thresholds derived from TDA to
             build graphs at different scales. The Laplacian eigenvectors
             of these graphs contain information which can be used to
             estimate tempos of the subdivisions. We show a proof of
             concept example on an audio snippet from the MIREX tempo
             training dataset, and we hope in future work to find a place
             for this in other MIR pipelines.},
   Key = {fds330396}
}

@article{fds330206,
   Author = {Tralie, CJ},
   Title = {Early MFCC And HPCP Fusion for Robust Cover Song
             Identification},
   Journal = {18th International Society for Music Information Retrieval
             (ISMIR)},
   Year = {2017},
   Month = {October},
   Abstract = {While most schemes for automatic cover song identification
             have focused on note-based features such as HPCP and chord
             profiles, a few recent papers surprisingly showed that local
             self-similarities of MFCC-based features also have
             classification power for this task. Since MFCC and HPCP
             capture complementary information, we design an unsupervised
             algorithm that combines normalized, beat-synchronous blocks
             of these features using cross-similarity fusion before
             attempting to locally align a pair of songs. As an added
             bonus, our scheme naturally incorporates structural
             information in each song to fill in alignment gaps where
             both feature sets fail. We show a striking jump in
             performance over MFCC and HPCP alone, achieving a state of
             the art mean reciprocal rank of 0.87 on the Covers80
             dataset. We also introduce a new medium-sized hand designed
             benchmark dataset called "Covers 1000," which consists of
             395 cliques of cover songs for a total of 1000 songs, and we
             show that our algorithm achieves an MRR of 0.9 on this
             dataset for the first correctly identified song in a clique.
             We provide the precomputed HPCP and MFCC features, as well
             as beat intervals, for all songs in the Covers 1000 dataset
             for use in further research.},
   Key = {fds330206}
}

@article{fds330207,
   Author = {Tralie, C},
   Title = {High Dimensional Geometry of Sliding Window Embeddings of
             Periodic Videos},
   Journal = {Proceedings of the 32st International Symposium on
             Computational Geometry (SOCG)},
   Year = {2016},
   Month = {June},
   Abstract = {We explore the high dimensional geometry of sliding windows
             of periodic videos. Under a reas- onable model for periodic
             videos, we show that the sliding window is necessary to
             disambiguate all states within a period, and we show that a
             video embedding with a sliding window of an appropriate
             dimension lies on a topological loop along a hypertorus.
             This hypertorus has an in- dependent ellipse for each
             harmonic of the motion. Natural motions with sharp
             transitions from foreground to background have many
             harmonics and are hence in higher dimensions, so linear
             subspace projections such as PCA do not accurately summarize
             the geometry of these videos. Noting this, we invoke tools
             from topological data analysis and cohomology to
             parameterize mo- tions in high dimensions with circular
             coordinates after the embeddings. We show applications to
             videos in which there is obvious periodic motion and to
             videos in which the motion is hidden.},
   Key = {fds330207}
}

@article{fds330208,
   Author = {Bendich, P and Gasparovic, E and Harer, J and Tralie,
             C},
   Title = {Geometric Models for Musical Audio Data},
   Journal = {Proceedings of the 32st International Symposium on
             Computational Geometry (SOCG)},
   Year = {2016},
   Month = {June},
   Key = {fds330208}
}

@article{fds330398,
   Author = {Tralie, CJ and Bendich, P},
   Title = {Cover Song Identification with Timbral Shape
             Sequences},
   Journal = {16th International Society for Music Information Retrieval
             (ISMIR)},
   Pages = {38-44},
   Year = {2015},
   Month = {October},
   Abstract = {We introduce a novel low level feature for identifying cover
             songs which quantifies the relative changes in the smoothed
             frequency spectrum of a song. Our key insight is that a
             sliding window representation of a chunk of audio can be
             viewed as a time-ordered point cloud in high dimensions. For
             corresponding chunks of audio between different versions of
             the same song, these point clouds are approximately rotated,
             translated, and scaled copies of each other. If we treat
             MFCC embeddings as point clouds and cast the problem as a
             relative shape sequence, we are able to correctly identify
             42/80 cover songs in the "Covers 80" dataset. By contrast,
             all other work to date on cover songs exclusively relies on
             matching note sequences from Chroma derived
             features.},
   Key = {fds330398}
}

@article{fds330209,
   Author = {Deyle, T and Tralie, CJ and Reynolds, MS and Kemp,
             CC},
   Title = {In-hand radio frequency identification (RFID) for robotic
             manipulation},
   Journal = {2013 Ieee International Conference on Robotics and
             Automation},
   Pages = {1234-1241},
   Publisher = {IEEE},
   Year = {2013},
   Month = {May},
   url = {http://dx.doi.org/10.1109/icra.2013.6630729},
   Abstract = {We present a unique multi-antenna RFID reader (a sensor)
             embedded in a robot's manipulator that is designed to
             operate with ordinary UHF RFID tags in a short-range,
             near-field electromagnetic regime. Using specially designed
             near-field antennas enables our sensor to obtain spatial
             information from tags at ranges of less than 1 meter. In
             this work, we characterize the near-field sensor's ability
             to detect tagged objects in the robots manipulator, present
             robot behaviors to determine the identity of a grasped
             object, and investigate how additional RF signal properties
             can be used for 'pre-touch' capabilities such as servoing to
             grasp an object. The future combination of long-range
             (far-field) and short-range (near-field) UHF RFID sensing
             has the potential to enable roboticists to jump-start
             applications by obviating or supplementing
             false-positive-prone visual object recognition. These
             techniques may be especially useful in the healthcare and
             service sectors, where mis-identification of an object (for
             example, a medication bottle) could have catastrophic
             consequences. © 2013 IEEE.},
   Doi = {10.1109/icra.2013.6630729},
   Key = {fds330209}
}

 

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