Parallel Online Time Warping for Real-Time Audio-to-Score Alignment in Multi-core Systems

[EN] The Audio-to-Score framework consists of two separate stages: pre- processing and alignment. The alignment is commonly solved through offline Dynamic Time Warping (DTW), which is a method to find the path over the distortion matrix with the minimum cost to determine the relation between the performance and the musical score times. In this work we propose a par- allel online DTW solution based on a client-server architecture. The current version of the application has been implemented for multi-core architectures (x86, x64 and ARM), thus covering either powerful systems or mobile devices. An extensive experimentation has been conducted in order to validate the software. The experiments also show that our framework allows to achieve a good score alignment within the real-time window by using parallel computing techniques.This work has been partially supported by Spanish Ministry of Science and Innovation and FEDER under Projects TEC2012-38142-C04-01, TEC2012-38142-C04-03, TEC2012-38142-C04-04, TEC2015-67387-C4-1-R, TEC2015-67387-C4-3-R, TEC2015-67387-C4-4-R, the European Union FEDER (CAPAP-H5 network TIN2014-53522-REDT), and the Generalitat Valenciana under Grant PROMETEOII/2014/003.Alonso-Jordá, P.; Cortina, R.; Rodríguez-Serrano, F.; Vera-Candeas, P.; Alonso-González, M.; Ranilla, J. (2017). Parallel Online Time Warping for Real-Time Audio-to-Score Alignment in Multi-core Systems. The Journal of Supercomputing. 73(1):126-138. https://doi.org/10.1007/s11227-016-1647-5S126138731Joder C, Essid S, Richard G (2011) A conditional random field framework for robust and scalable audio-to-score matching. 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In: Proceedings of the international computer music conference (ICMC), pp 129–132Simon I, Morris D, Basu S (2008) MySong: automatic accompaniment generation for vocal melodies. In: Proceedings of the SIGCHI conference on human factors in computing systems. ACM, New York, pp 725–734Rodriguez-Serrano FJ, Duan Z, Vera-Candeas P, Pardo B, Carabias-Orti JJ (2015) Online score-informed source separation with adaptive instrument models. J New Music Res Lond 44(2):83–96Arzt A, Widmer G, Dixon S (2008) Automatic page turning for musicians via real-time machine listening. In: Proceedings of the 18th European conference on artificial intelligence. IOS Press, Amsterdam, pp 241–245Carabias-Orti JJ, Rodriguez-Serrano FJ, Vera-Candeas P, Canadas-Quesada FJ, Ruiz-Reyes N (2015) An audio to score alignment framework using spectral factorization and dynamic time warping. In: 16th International Society for music information retrieval conference, pp 742–748Rodríguez-Serrano FJ, Menéndez-Canal J, Vidal A, Cañadas-Quesada FJ, Cortina R (2015) A DTW based score following method for score-informed sound source separation. In: Proceedings of the 12th sound and music computing conference 2015 (SMC-15), Ireland, pp 491–496Carabias-Ortí JJ, Rodríguez-Serrano FJ, Vera-Candeas P, Cañadas-Quesada FJ, Ruíz-Reyes N (2013) Constrained non-negative sparse coding using learnt instrument templates for realtime music transcription. Eng Appl Artif Intell 26(7):1671–1680Raphael C (2006) Aligning music audio with symbolic scores using a hybrid graphical model. Mach Learn 65:389–409Schreck-Ensemble (2001–2004) ComParser 1.42. http://home.hku.nl/~pieter.suurmond/SOFT/CMP/doc/cmp.html . Accessed Sept 2015Itakura F (1975) Minimum prediction residual principle applied to speech recognition. 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Real-time Soundprism

[EN] This paper presents a parallel real-time sound source separation system for decomposing an audio signal captured with a single microphone in so many audio signals as the number of instruments that are really playing. This approach is usually known as Soundprism. The application scenario of the system is for a concert hall in which users, instead of listening to the mixed audio, want to receive the audio of just an instrument, focusing on a particular performance. The challenge is even greater since we are interested in a real-time system on handheld devices, i.e., devices characterized by both low power consumption and mobility. The results presented show that it is possible to obtain real-time results in the tested scenarios using an ARM processor aided by a GPU, when this one is present.This work has been supported by the "Ministerio de Economia y Competitividad" of Spain and FEDER under projects TEC2015-67387-C4-{1,2,3}-R.Muñoz-Montoro, AJ.; Ranilla, J.; Vera-Candeas, P.; Combarro, EF.; Alonso-Jordá, P. (2019). Real-time Soundprism. The Journal of Supercomputing. 75(3):1594-1609. https://doi.org/10.1007/s11227-018-2703-0S15941609753Alonso P, Cortina R, Rodríguez-Serrano FJ, Vera-Candeas P, Alonso-González M, Ranilla J (2017) Parallel online time warping for real-time audio-to-score alignment in multi-core systems. J Supercomput 73:126. https://doi.org/10.1007/s11227-016-1647-5Carabias-Orti JJ, Cobos M, Vera-Candeas P, Rodríguez-Serrano FJ (2013) Nonnegative signal factorization with learnt instrument models for sound source separation in close-microphone recordings. EURASIP J Adv Signal Process 2013:184. https://doi.org/10.1186/1687-6180-2013-184Carabias-Orti JJ, Rodriguez-Serrano FJ, Vera-Candeas P, Canadas-Quesada FJ, Ruiz-Reyes N (2015) An audio to score alignment framework using spectral factorization and dynamic time warping. In: 16th International Society for Music Information Retrieval Conference, pp 742–748Díaz-Gracia N, Cocaña-Fernández A, Alonso-González M, Martínez-Zaldívar FJ, Cortina R, García-Mollá VM, Alonso P, Ranilla J (2014) NNMFPACK: a versatile approach to an NNMF parallel library. In: Proceedings of the 2014 International Conference on Computational and Mathematical Methods in Science and Engineering, pp 456–465Díaz-Gracia N, Cocaña-Fernández A, Alonso-González M, Martínez-Zaldívar FJ, Cortina R, García-Mollá VM, Vidal AM (2015) Improving NNMFPACK with heterogeneous and efficient kernels for $$\beta$$ β -divergence metrics. J Supercomput 71:1846–1856. https://doi.org/10.1007/s11227-014-1363-yDriedger J, Grohganz H, Prätzlich T, Ewert S, Müller M (2013) Score-informed audio decomposition and applications. In: Proceedings of the 21st ACM International Conference on Multimedia, pp 541–544Duan Z, Pardo B (2011) Soundprism: an online system for score-informed source separation of music audio. IEEE J Sel Top Signal Process 5(6):1205–1215Duong NQ, Vincent E, Gribonval R (2010) Under-determined reverberant audio source separation using a full-rank spatial covariance model. IEEE Trans Audio Speech 18(7):1830–1840. https://doi.org/10.1109/TASL.2010.2050716Ewert S, Müller M (2011) Estimating note intensities in music recordings. In: Proceedings of the IEEE International Conference on Acoustics, Speech, and Signal Processing, pp 385–388Ewert S, Pardo B, Mueller M, Plumbley MD (2014) Score-informed source separation for musical audio recordings: an overview. IEEE Signal Process Mag 31:116–124. https://doi.org/10.1109/MSP.2013.2296076Fastl H, Zwicker E (2007) Psychoacoustics. Springer, BerlinGanseman J, Scheunders P, Mysore GJ, Abel JS (2010) Source separation by score synthesis. Int Comput Music Conf 2010:1–4Goto M, Hashiguchi H, Nishimura T, Oka R (2002) RWC music database: popular, classical and jazz music databases. In: ISMIR, vol 2, pp 287–288Goto M (2004) Development of the RWC music database. In: Proceedings of the 18th International Congress on Acoustics (ICA 2004), ppp 553–556Hennequin R, David B, Badeau R (2011) Score informed audio source separation using a parametric model of non-negative spectrogram. In: 2011 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) pp 45–48. https://doi.org/10.1109/ICASSP.2011.5946324Itoyama K, Goto M, Komatani K et al (2008) Instrument equalizer for query-by-example retrieval: improving sound source separation based on integrated harmonic and inharmonic models. In: ISMIR. https://doi.org/10.1136/bmj.324.7341.827Marxer R, Janer J, Bonada J (2012) Low-latency instrument separation in polyphonic audio using timbre models. In: International Conference on Latent Variable Analysis and Signal Separation, pp 314–321Miron M, Carabias-Orti JJ, Janer J (2015) Improving score-informed source separation for classical music through note refinement. In: ISMIR, pp 448–454Ozerov A, Févotte C (2010) Multichannel nonnegative matrix factorization in convolutive mixtures for audio source separation. IEEE Trans Audio Speech Lang Process 18:550–563. https://doi.org/10.1109/TASL.2009.2031510Ozerov A, Vincent E, Bimbot F (2012) A general flexible framework for the handling of prior information in audio source separation. IEEE Trans Audio Speech Lang Process 20:1118–1133. https://doi.org/10.1109/TASL.2011.2172425Pätynen J, Pulkki V, Lokki T (2008) Anechoic recording system for symphony orchestra. Acta Acust United Acust 94:856–865. https://doi.org/10.3813/AAA.918104Raphael C (2008) A classifier-based approach to score-guided source separation of musical audio. Comput Music J 32:51–59. https://doi.org/10.1162/comj.2008.32.1.51Rodriguez-Serrano FJ, Duan Z, Vera-Candeas P, Pardo B, Carabias-Orti JJ (2015) Online score-informed source separation with adaptive instrument models. J New Music Res 44:83–96. https://doi.org/10.1080/09298215.2014.989174Rodriguez-Serrano FJ, Carabias-Orti JJ, Vera-Candeas P, Martinez-Munoz D (2016) Tempo driven audio-to-score alignment using spectral decomposition and online dynamic time warping. ACM Trans Intell Syst Technol 8:1–20. https://doi.org/10.1145/2926717Sawada H, Araki S, Makino S (2011) Underdetermined convolutive blind source separation via frequency bin-wise clustering and permutation alignment. 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HReMAS: Hybrid Real-time Musical Alignment System

[EN] This paper presents a real-time audio-to-score alignment system for musical applications. The aim of these systems is to synchronize a live musical performance with its symbolic representation in a music sheet. We have used as a base our previous real-time alignment system by enhancing it with a traceback stage, a stage used in offline alignment to improve the accuracy of the aligned note. This stage introduces some delay, what forces to assume a trade-off between output delay and alignment accuracy that must be considered in the design of this type of hybrid techniques. We have also improved our former system to execute faster in order to minimize this delay. Other interesting improvements, like identification of silence frames, have also been incorporated to our proposed system.This work has been supported by the "Ministerio de Economia y Competitividad" of Spain and FEDER under Projects TEC2015-67387-C4-{1,2,3}-R.Cabañas-Molero, P.; Cortina-Parajón, R.; Combarro, EF.; Alonso-Jordá, P.; Bris-Peñalver, FJ. (2019). HReMAS: Hybrid Real-time Musical Alignment System. The Journal of Supercomputing. 75(3):1001-1013. https://doi.org/10.1007/s11227-018-2265-1S10011013753Alonso P, Cortina R, Rodríguez-Serrano FJ, Vera-Candeas P, Alonso-González M, Ranilla J (2017) Parallel online time warping for real-time audio-to-score alignment in multi-core systems. J Supercomput 73(1):126–138Alonso P, Vera-Candeas P, Cortina R, Ranilla J (2017) An efficient musical accompaniment parallel system for mobile devices. J Supercomput 73(1):343–353Arzt A (2016) Flexible and robust music tracking. Ph.D. thesis, Johannes Kepler University Linz, Linz, ÖsterreichArzt A, Widmer G, Dixon S (2008) Automatic page turning for musicians via real-time machine listening. In: Proceedings of the 18th European Conference on Artificial Intelligence (ECAI), Amsterdam, pp 241–245Carabias-Orti J, Rodríguez-Serrano F, Vera-Candeas P, Ruiz-Reyes N, Cañadas-Quesada F (2015) An audio to score alignment framework using spectral factorization and dynamic time warping. In: Proceedings of ISMIR, pp 742–748Cont A (2006) Realtime audio to score alignment for polyphonic music instruments, using sparse non-negative constraints and hierarchical HMMs. In: 2006 IEEE International Conference on Acoustics Speech and Signal Processing Proceedings, vol 5. pp V–VCont A, Schwarz D, Schnell N, Raphael C (2007) Evaluation of real-time audio-to-score alignment. In: International Symposium on Music Information Retrieval (ISMIR), ViennaDannenberg RB, Raphael C (2006) Music score alignment and computer accompaniment. Commun ACM 49(8):38–43Devaney J, Ellis D (2009) Handling asynchrony in audio-score alignment. In: Proceedings of the International Computer Music Conference Computer Music Association. pp 29–32Dixon S (2005) An on-line time warping algorithm for tracking musical performances. In: Proceedings of the International Joint Conference on Artificial Intelligence (IJCAI). pp 1727–1728Duan Z, Pardo B (2011) Soundprism: an online system for score-informed source separation of music audio. IEEE J Sel Top Signal Process 5(6):1205–1215Ewert S, Muller M, Grosche P (2009) High resolution audio synchronization using chroma onset features. In: IEEE International Conference on Acoustics, Speech and Signal Processing, 2009 (ICASSP 2009). pp 1869–1872Hu N, Dannenberg R, Tzanetakis G (2003) Polyphonic audio matching and alignment for music retrieval. In: 2003 IEEE Workshop on Applications of Signal Processing to Audio and Acoustics. pp 185–188Kaprykowsky H, Rodet X (2006) Globally optimal short-time dynamic time warping, application to score to audio alignment. In: Proceedings of the International Conference on Acoustics, Speech and Signal Processing, vol 5. pp. V–VLi B, Duan Z (2016) An approach to score following for piano performances with the sustained effect. IEEE/ACM Trans Audio Speech Lang Process 24(12):2425–2438Miron M, Carabias-Orti JJ, Bosch JJ, Gómez E, Janer J (2016) Score-informed source separation for multichannel orchestral recordings. J Electr Comput Eng 2016(8363507):1–19Muñoz-Montoro A, Cabañas-Molero P, Bris-Peñalver F, Combarro E, Cortina R, Alonso P (2017) Discovering the composition of audio files by audio-to-midi alignment. In: Proceedings of the 17th International Conference on Computational and Mathematical Methods in Science and Engineering. pp 1522–1529Orio N, Schwarz D (2001) Alignment of monophonic and polyphonic music to a score. In: Proceedings of the International Computer Music Conference (ICMC), pp 155–158Pätynen J, Pulkki V, Lokki T (2008) Anechoic recording system for symphony orchestra. Acta Acust United Acust 94(6):856–865Raphael C (2010) Music plus one and machine learning. In: Proceedings of the 27th International Conference on Machine Learning (ICML), pp 21–28Rodriguez-Serrano FJ, Carabias-Orti JJ, Vera-Candeas P, Martinez-Munoz D (2016) Tempo driven audio-to-score alignment using spectral decomposition and online dynamic time warping. ACM Trans Intell Syst Technol 8(2):22:1–22:2

A Prospective Study of Aspirin Use and the Risk of Gastrointestinal Bleeding in Men

Data regarding the influence of dose and duration of aspirin use on risk of gastrointestinal bleeding are conflicting.We conducted a prospective cohort study of 32,989 men enrolled in the Health Professionals Follow-up Study (HPFS) in 1994 who provided biennial aspirin data. We estimated relative risk of major gastrointestinal bleeding requiring hospitalization or a blood transfusion.During 14 years of follow-up, 707 men reported an episode of major gastrointestinal bleeding over 377,231 person-years. After adjusting for risk factors, regular aspirin use (≥2 times/week) had a multivariate relative risk (RR) of gastrointestinal bleeding of 1.32 (95% confidence interval [CI], 1.12-1.55) compared to non-regular use. The association was particularly evident for upper gastrointestinal bleeding (multivariate RR, 1.49; 95% CI, 1.16-1.92). Compared to men who denied any aspirin use, multivariate RRs of upper gastrointestinal bleeding were 1.05 (95% CI 0.71-1.52) for men who used 0.5-1.5 standard tablets/week, 1.31 (95% CI 0.88-1.95) for 2-5 aspirin/week, 1.63 (95% CI, 1.15-2.32) for 6-14 aspirin/week and 2.40 (95% CI, 1.10-5.22) for >14 aspirin/week (P(trend)<0.001). The relative risk also appeared to be dose-dependent among short-term users <5 years; P(trend)<.001) and long-term users (≥5 years; P(trend) = 0.015). In contrast, after controlling for dose, increasing duration of use did not appear to be associated with risk (P(trend) = 0.749).Regular aspirin use increases the risk of gastrointestinal bleeding, especially from the upper tract. However, risk of bleeding appears to be more strongly related to dose than to duration of use. Risk of bleeding should be minimized by using the lowest effective dose among short-term and long-term aspirin users

Associations between Screen Time and Physical Activity among Spanish Adolescents

Excessive time in front of a single or several screens could explain a displacement of physical activity. The present study aimed at determining whether screen-time is associated with a reduced level of moderate to vigorous physical activity (MVPA) in Spanish adolescents living in favorable environmental conditions. or more to total screen-time showed a 64% (OR = 0.61, 95% CI, 0.44–0.86) increased risk of failing to achieve the recommended adolescent MVPA level. Participation in organized physical activities and sports competitions were more strongly associated with MVPA than screen-related behaviors.No single screen-related behavior explained the reduction of MVPA in adolescents. However, the total time accumulated through several screen-related behaviors was negatively associated with MVPA level in boys. This association could be due to lower availability of time for exercise as the time devoted to sedentary screen-time activities increases. Participation in organized physical activities seems to counteract the negative impact of excessive time in front of screens on physical activity

Dark Energy Survey Year 3 Results: Galaxy mock catalogs for BAO analysis

The calibration and validation of scientific analysis in simulations is a fundamental tool to ensure unbiased and robust results in observational cosmology. In particular, mock galaxy catalogs are a crucial resource to achieve these goals in the measurement of baryon acoustic oscillation (BAO) in the clustering of galaxies. Here we present a set of 1952 galaxy mock catalogs designed to mimic the Dark Energy Survey Year 3 BAO sample over its full photometric redshift range 0.6 < zphoto < 1.1. The mocks are based upon 488 ICE-COLA fast N-body simulations of full-sky light cones and were created by populating halos with galaxies, using a hybrid halo occupation distribution – halo abundance matching model. This model has ten free parameters, which were determined, for the first time, using an automatic likelihood minimization procedure. We also introduced a novel technique to assign photometric redshift for simulated galaxies, following a two-dimensional probability distribution with VIMOS Public Extragalactic Redshift Survey data. The calibration was designed to match the observed abundance of galaxies as a function of photometric redshift, the distribution of photometric redshift errors, and the clustering amplitude on scales smaller than those used for BAO measurements. An exhaustive analysis was done to ensure that the mocks reproduce the input properties. Finally, mocks were tested by comparing the angular correlation function w(θ), angular power spectrum Cℓ, and projected clustering ξp(r⊥) to theoretical predictions and data. The impact of volume replication in the estimate of the covariance is also investigated. The success in accurately reproducing the photometric redshift uncertainties and the galaxy clustering as a function of redshift render this mock creation pipeline as a benchmark for future analyses of photometric galaxy surveys

MAPK pathway activation in pilocytic astrocytoma

Pilocytic astrocytoma (PA) is the most common tumor of the pediatric central nervous system (CNS). A body of research over recent years has demonstrated a key role for mitogen-activated protein kinase (MAPK) pathway signaling in the development and behavior of PAs. Several mechanisms lead to activation of this pathway in PA, mostly in a mutually exclusive manner, with constitutive BRAF kinase activation subsequent to gene fusion being the most frequent. The high specificity of this fusion to PA when compared with other CNS tumors has diagnostic utility. In addition, the frequency of alteration of this key pathway provides an opportunity for molecularly targeted therapy in this tumor. Here, we review the current knowledge on mechanisms of MAPK activation in PA and some of the downstream consequences of this activation, which are now starting to be elucidated both in vitro and in vivo, as well as clinical considerations and possible future directions

Dark Energy Survey Year 3 Results: Measuring the Survey Transfer Function with Balrog

We describe an updated calibration and diagnostic framework, Balrog, used to directly sample the selection and photometric biases of the Dark Energy Survey (DES) Year 3 (Y3) data set. We systematically inject onto the single-epoch images of a random 20% subset of the DES footprint an ensemble of nearly 30 million realistic galaxy models derived from DES Deep Field observations. These augmented images are analyzed in parallel with the original data to automatically inherit measurement systematics that are often too difficult to capture with generative models. The resulting object catalog is a Monte Carlo sampling of the DES transfer function and is used as a powerful diagnostic and calibration tool for a variety of DES Y3 science, particularly for the calibration of the photometric redshifts of distant "source" galaxies and magnification biases of nearer "lens" galaxies. The recovered Balrog injections are shown to closely match the photometric property distributions of the Y3 GOLD catalog, particularly in color, and capture the number density fluctuations from observing conditions of the real data within 1% for a typical galaxy sample. We find that Y3 colors are extremely well calibrated, typically within ∼1–8 mmag, but for a small subset of objects, we detect significant magnitude biases correlated with large overestimates of the injected object size due to proximity effects and blending. We discuss approaches to extend the current methodology to capture more aspects of the transfer function and reach full coverage of the survey footprint for future analyses

Lensing without borders. I. A blind comparison of the amplitude of galaxy-galaxy lensing between independent imaging surveys

Lensing Without Borders is a cross-survey collaboration created to assess the consistency of galaxy-galaxy lensing signals (ΔΣ) across different data-sets and to carry out end-to-end tests of systematic errors. We perform a blind comparison of the amplitude of ΔΣ using lens samples from BOSS and six independent lensing surveys. We find good agreement between empirically estimated and reported systematic errors which agree to better than 2.3σ in four lens bins and three radial ranges. For lenses with zL &amp;gt; 0.43 and considering statistical errors, we detect a 3-4σ correlation between lensing amplitude and survey depth. This correlation could arise from the increasing impact at higher redshift of unrecognised galaxy blends on shear calibration and imperfections in photometric redshift calibration. At zL &amp;gt; 0.54 amplitudes may additionally correlate with foreground stellar density. The amplitude of these trends is within survey-defined systematic error budgets which are designed to include known shear and redshift calibration uncertainty. Using a fully empirical and conservative method, we do not find evidence for large unknown systematics. Systematic errors greater than 15 per cent (25 per cent) ruled out in three lens bins at 68 per cent (95 per cent) confidence at z &amp;lt; 0.54. Differences with respect to predictions based on clustering are observed to be at the 20-30 per cent level. Our results therefore suggest that lensing systematics alone are unlikely to fully explain the ‘lensing is low’ effect at z &amp;lt; 0.54. This analysis demonstrates the power of cross-survey comparisons and provides a promising path for identifying and reducing systematics in future lensing analyses