Statistical Piano Reduction Controlling Performance Difficulty

We present a statistical-modelling method for piano reduction, i.e. converting an ensemble score into piano scores, that can control performance difficulty. While previous studies have focused on describing the condition for playable piano scores, it depends on player's skill and can change continuously with the tempo. We thus computationally quantify performance difficulty as well as musical fidelity to the original score, and formulate the problem as optimization of musical fidelity under constraints on difficulty values. First, performance difficulty measures are developed by means of probabilistic generative models for piano scores and the relation to the rate of performance errors is studied. Second, to describe musical fidelity, we construct a probabilistic model integrating a prior piano-score model and a model representing how ensemble scores are likely to be edited. An iterative optimization algorithm for piano reduction is developed based on statistical inference of the model. We confirm the effect of the iterative procedure; we find that subjective difficulty and musical fidelity monotonically increase with controlled difficulty values; and we show that incorporating sequential dependence of pitches and fingering motion in the piano-score model improves the quality of reduction scores in high-difficulty cases.Comment: 12 pages, 7 figures, version accepted to APSIPA Transactions on Signal and Information Processin

Guitar Chords Classification Using Uncertainty Measurements of Frequency Bins

This paper presents a method to perform chord classification from recorded audio. The signal harmonics are obtained by using the Fast Fourier Transform, and timbral information is suppressed by spectral whitening. A multiple fundamental frequency estimation of whitened data is achieved by adding attenuated harmonics by a weighting function. This paper proposes a method that performs feature selection by using a thresholding of the uncertainty of all frequency bins. Those measurements under the threshold are removed from the signal in the frequency domain. This allows a reduction of 95.53% of the signal characteristics, and the other 4.47% of frequency bins are used as enhanced information for the classifier. An Artificial Neural Network was utilized to classify four types of chords: major, minor, major 7th, and minor 7th. Those, played in the twelve musical notes, give a total of 48 different chords. Two reference methods (based on Hidden Markov Models) were compared with the method proposed in this paper by having the same database for the evaluation test. In most of the performed tests, the proposed method achieved a reasonably high performance, with an accuracy of 93%

AutoRhythmGuitar: Computer-aided Composition for Rhythm Guitar in the Tab Space

(Abstract to follow

Melody Harmonization

Vedci z oboru informačných technológií oddávna považovali hudbu za obzvlášť zaujímavé umenie. Pravdou je, že história hudby tvorenej počítačom je skoro tak dlhá ako história počítačovej vedy. Programy pre komponovanie, alebo tvorenie hudby" na rôznych úrovniach procesu kompozície boli vyvíjané už od 50tych rokov minulého storočia. Táto bakalárska práca uvádza hlavné prístupy v oblasti automatickej harmonizácie t.j. Problém produkovania hudobného aranžmá (nôt) z daných melódií, a sústreďuje sa na najpoužívanejšie techniky jeho riešenia. Hlavným cieľom tejto práce je návrh a implementácia softvérového systému pre automatickú harmonizáciu, ktorý by mal byť schopný naučiť sa pravidlá harmónie z databázy midi súborov. V tejto práci popíšem existujúce harmonizačné systémy a ďalej sa zameriam hlavne na princípy strojového učenia - teóriu a aplikáciu umelých neurónových sietí a ich použitie pre harmonizáciu.Computer scientists have long been considering music as a particularly interesting art Indeed, the history of computer music is almost as long as the history of computer science. Programs to compose music, or to make music" at various levels of the composition process have been designed since the 50s. This bachelor's thesis surveys the main approaches in the field of automatic harmonization, i.e. the problem of producing musical arrangements (scores) from given melodies, and focuses on the most widely used techniques to do so. The main goal of this paper is the issue of design and implementation of a software system for an automatic music harmonization which should learn the rules of harmony from the database of midi file. In the paper. In this thesis I describe existing systems for harmonization and furthermore I focus mainly on principles of machine learning - theory and application of Artificial Neural Networks and their use for harmonization.

AI Methods in Algorithmic Composition: A Comprehensive Survey

Algorithmic composition is the partial or total automation of the process of music composition by using computers. Since the 1950s, different computational techniques related to Artificial Intelligence have been used for algorithmic composition, including grammatical representations, probabilistic methods, neural networks, symbolic rule-based systems, constraint programming and evolutionary algorithms. This survey aims to be a comprehensive account of research on algorithmic composition, presenting a thorough view of the field for researchers in Artificial Intelligence.This study was partially supported by a grant for the MELOMICS project (IPT-300000-2010-010) from the Spanish Ministerio de Ciencia e Innovación, and a grant for the CAUCE project (TSI-090302-2011-8) from the Spanish Ministerio de Industria, Turismo y Comercio. The first author was supported by a grant for the GENEX project (P09-TIC- 5123) from the Consejería de Innovación y Ciencia de Andalucía

Shape Representation in Primate Visual Area 4 and Inferotemporal Cortex

The representation of contour shape is an essential component of object recognition, but the cortical mechanisms underlying it are incompletely understood, leaving it a fundamental open question in neuroscience. Such an understanding would be useful theoretically as well as in developing computer vision and Brain-Computer Interface applications. We ask two fundamental questions: “How is contour shape represented in cortex and how can neural models and computer vision algorithms more closely approximate this?” We begin by analyzing the statistics of contour curvature variation and develop a measure of salience based upon the arc length over which it remains within a constrained range. We create a population of V4-like cells – responsive to a particular local contour conformation located at a specific position on an object’s boundary – and demonstrate high recognition accuracies classifying handwritten digits in the MNIST database and objects in the MPEG-7 Shape Silhouette database. We compare the performance of the cells to the “shape-context” representation (Belongie et al., 2002) and achieve roughly comparable recognition accuracies using a small test set. We analyze the relative contributions of various feature sensitivities to recognition accuracy and robustness to noise. Local curvature appears to be the most informative for shape recognition. We create a population of IT-like cells, which integrate specific information about the 2-D boundary shapes of multiple contour fragments, and evaluate its performance on a set of real images as a function of the V4 cell inputs. We determine the sub-population of cells that are most effective at identifying a particular category. We classify based upon cell population response and obtain very good results. We use the Morris-Lecar neuronal model to more realistically illustrate the previously explored shape representation pathway in V4 – IT. We demonstrate recognition using spatiotemporal patterns within a winnerless competition network with FitzHugh-Nagumo model neurons. Finally, we use the Izhikevich neuronal model to produce an enhanced response in IT, correlated with recognition, via gamma synchronization in V4. Our results support the hypothesis that the response properties of V4 and IT cells, as well as our computer models of them, function as robust shape descriptors in the object recognition process

심층 신경망 기반의 음악 리드 시트 자동 채보 및 멜로디 유사도 평가

학위논문(박사) -- 서울대학교대학원 : 공과대학 산업공학과, 2023. 2. 이경식.Since the composition, arrangement, and distribution of music became convenient thanks to the digitization of the music industry, the number of newly supplied music recordings is increasing. Recently, due to platform environments being established whereby anyone can become a creator, user-created music such as their songs, cover songs, and remixes is being distributed through YouTube and TikTok. With such a large volume of musical recordings, the demand to transcribe music into sheet music has always existed for musicians. However, it requires musical knowledge and is time-consuming. This thesis studies automatic lead sheet transcription using deep neural networks. The development of transcription artificial intelligence (AI) can greatly reduce the time and cost for people in the music industry to find or transcribe sheet music. In addition, since the conversion from music sources to the form of digital music is possible, the applications could be expanded, such as music plagiarism detection and music composition AI. The thesis first proposes a model recognizing chords from audio signals. Chord recognition is an important task in music information retrieval since chords are highly abstract and descriptive features of music. We utilize a self-attention mechanism for chord recognition to focus on certain regions of chords. Through an attention map analysis, we visualize how attention is performed. It turns out that the model is able to divide segments of chords by utilizing the adaptive receptive field of the attention mechanism. This thesis proposes a note-level singing melody transcription model using sequence-to-sequence transformers. Overlapping decoding is introduced to solve the problem of the context between segments being broken. Applying pitch augmentation and adding a noisy dataset with data cleansing turns out to be effective in preventing overfitting and generalizing the model performance. Ablation studies demonstrate the effects of the proposed techniques in note-level singing melody transcription, both quantitatively and qualitatively. The proposed model outperforms other models in note-level singing melody transcription performance for all the metrics considered. Finally, subjective human evaluation demonstrates that the results of the proposed models are perceived as more accurate than the results of a previous study. Utilizing the above research results, we introduce the entire process of an automatic music lead sheet transcription. By combining various music information recognized from audio signals, we show that it is possible to transcribe lead sheets that express the core of popular music. Furthermore, we compare the results with lead sheets transcribed by musicians. Finally, we propose a melody similarity assessment method based on self-supervised learning by applying the automatic lead sheet transcription. We present convolutional neural networks that express the melody of lead sheet transcription results in embedding space. To apply self-supervised learning, we introduce methods of generating training data by musical data augmentation techniques. Furthermore, a loss function is presented to utilize the training data. Experimental results demonstrate that the proposed model is able to detect similar melodies of popular music from plagiarism and cover song cases.음악 산업의 디지털화를 통해 음악의 작곡, 편곡 및 유통이 편리해졌기 때문에 새롭게 공급되는 음원의 수가 증가하고 있다. 최근에는 누구나 크리에이터가 될 수 있는 플랫폼 환경이 구축되어, 사용자가 만든 자작곡, 커버곡, 리믹스 등이 유튜브, 틱톡을 통해 유통되고 있다. 이렇게 많은 양의 음악에 대해, 음악을 악보로 채보하고자 하는 수요는 음악가들에게 항상 존재했다. 그러나 악보 채보에는 음악적 지식이 필요하고, 시간과 비용이 많이 소요된다는 문제점이 있다. 본 논문에서는 심층 신경망을 활용하여 음악 리드 시트 악보 자동 채보 기법을 연구한다. 채보 인공지능의 개발은 음악 종사자 및 연주자들이 악보를 구하거나 만들기 위해 소모하는 시간과 비용을 크게 줄여 줄 수 있다. 또한 음원에서 디지털 악보 형태로 변환이 가능해지므로, 자동 표절 탐지, 작곡 인공지능 학습 등 다양하게 활용이 가능하다. 리드 시트 채보를 위해, 먼저 오디오 신호로부터 코드를 인식하는 모델을 제안한다. 음악에서 코드는 함축적이고 표현적인 음악의 중요한 특징이므로 이를 인식하는 것은 매우 중요하다. 코드 구간 인식을 위해, 어텐션 매커니즘을 이용하는 트랜스포머 기반 모델을 제시한다. 어텐션 지도 분석을 통해, 어텐션이 실제로 어떻게 적용되는지 시각화하고, 모델이 코드의 구간을 나누고 인식하는 과정을 살펴본다. 그리고 시퀀스 투 시퀀스 트랜스포머를 이용한 음표 수준의 가창 멜로디 채보 모델을 제안한다. 디코딩 과정에서 각 구간 사이의 문맥 정보가 단절되는 문제를 해결하기 위해 중첩 디코딩을 도입한다. 데이터 변형 기법으로 음높이 변형을 적용하는 방법과 데이터 클렌징을 통해 학습 데이터를 추가하는 방법을 소개한다. 정량 및 정성적인 비교를 통해 제안한 기법들이 성능 개선에 도움이 되는 것을 확인하였고, 제안모델이 MIR-ST500 데이터 셋에 대한 음표 수준의 가창 멜로디 채보 성능에서 가장 우수한 성능을 보였다. 추가로 주관적인 사람의 평가에서 제안 모델의 채보 결과가 이전 모델보다 저 정확하다고 인식됨을 확인하였다. 앞의 연구의 결과를 활용하여, 음악 리드 시트 자동 채보의 전체 과정을 제시한다. 오디오 신호로부터 인식한 다양한 음악 정보를 종합하여, 대중 음악 오디오 신호의 핵심을 표현하는 리드 시트 악보 채보가 가능함을 보인다. 그리고 이를 전문가가 제작한 리드시트와 비교하여 분석한다. 마지막으로 리드 시트 악보 자동 채보 기법을 응용하여, 자기 지도 학습 기반 멜로디 유사도 평가 방법을 제안한다. 리드 시트 채보 결과의 멜로디를 임베딩 공간에 표현하는 합성곱 신경망 모델을 제시한다. 자기지도 학습 방법론을 적용하기 위해, 음악적 데이터 변형 기법을 적용하여 학습 데이터를 생성하는 방법을 제안한다. 그리고 준비된 학습 데이터를 활용하는 심층 거리 학습 손실함수를 설계한다. 실험 결과 분석을 통해, 제안 모델이 표절 및 커버송 케이스에서 대중음악의 유사한 멜로디를 탐지할 수 있음을 확인한다.Chapter 1 Introduction 1 1.1 Background and Motivation 1 1.2 Objectives 4 1.3 Thesis Outline 6 Chapter 2 Literature Review 7 2.1 Attention Mechanism and Transformers 7 2.1.1 Attention-based Models 7 2.1.2 Transformers with Musical Event Sequence 8 2.2 Chord Recognition 11 2.3 Note-level Singing Melody Transcription 13 2.4 Musical Key Estimation 15 2.5 Beat Tracking 17 2.6 Music Plagiarism Detection and Cover Song Identi cation 19 2.7 Deep Metric Learning and Triplet Loss 21 Chapter 3 Problem De nition 23 3.1 Lead Sheet Transcription 23 3.1.1 Chord Recognition 24 3.1.2 Singing Melody Transcription 25 3.1.3 Post-processing for Lead Sheet Representation 26 3.2 Melody Similarity Assessment 28 Chapter 4 A Bi-directional Transformer for Musical Chord Recognition 29 4.1 Methodology 29 4.1.1 Model Architecture 29 4.1.2 Self-attention in Chord Recognition 33 4.2 Experiments 35 4.2.1 Datasets 35 4.2.2 Preprocessing 35 4.2.3 Evaluation Metrics 36 4.2.4 Training 37 4.3 Results 38 4.3.1 Quantitative Evaluation 38 4.3.2 Attention Map Analysis 41 Chapter 5 Note-level Singing Melody Transcription 44 5.1 Methodology 44 5.1.1 Monophonic Note Event Sequence 44 5.1.2 Audio Features 45 5.1.3 Model Architecture 46 5.1.4 Autoregressive Decoding and Monophonic Masking 47 5.1.5 Overlapping Decoding 47 5.1.6 Pitch Augmentation 49 5.1.7 Adding Noisy Dataset with Data Cleansing 50 5.2 Experiments 51 5.2.1 Dataset 51 5.2.2 Experiment Con gurations 52 5.2.3 Evaluation Metrics 53 5.2.4 Comparison Models 54 5.2.5 Human Evaluation 55 5.3 Results 56 5.3.1 Ablation Study 56 5.3.2 Note-level Transcription Model Comparison 59 5.3.3 Transcription Performance Distribution Analysis 59 5.3.4 Fundamental Frequency (F0) Metric Evaluation 60 5.4 Qualitative Analysis 62 5.4.1 Visualization of Ablation Study 62 5.4.2 Spectrogram Analysis 65 5.4.3 Human Evaluation 67 Chapter 6 Automatic Music Lead Sheet Transcription 68 6.1 Post-processing for Lead Sheet Representation 68 6.2 Lead Sheet Transcription Results 71 Chapter 7 Melody Similarity Assessment with Self-supervised Convolutional Neural Networks 77 7.1 Methodology 77 7.1.1 Input Data Representation 77 7.1.2 Data Augmentation 78 7.1.3 Model Architecture 82 7.1.4 Loss Function 84 7.1.5 De nition of Distance between Songs 85 7.2 Experiments 87 7.2.1 Dataset 87 7.2.2 Training 88 7.2.3 Evaluation Metrics 88 7.3 Results 89 7.3.1 Quantitative Evaluation 89 7.3.2 Qualitative Evaluation 99 Chapter 8 Conclusion 107 8.1 Summary and Contributions 107 8.2 Limitations and Future Research 110 Bibliography 111 국문초록 126박

Biomechanical Modelling of Musical Performance: A Case Study of the Guitar

Merged with duplicate record 10026.1/2517 on 07.20.2017 by CS (TIS)Computer-generated musical performances are often criticised for being unable to match the expressivity found in performances by humans. Much research has been conducted in the past two decades in order to create computer technology able to perform a given piece music as expressively as humans, largely without success. Two approaches have been often adopted to research into modelling expressive music performance on computers. The first focuses on sound; that is, on modelling patterns of deviations between a recorded human performance and the music score. The second focuses on modelling the cognitive processes involved in a musical performance. Both approaches are valid and can complement each other. In this thesis we propose a third complementary approach, focusing on the guitar, which concerns the physical manipulation of the instrument by the performer: a biomechanical approach. The essence of this thesis is a study on capturing, analyzing and modelling information about motor and biomechanical processes of guitar performance. The focus is on speed, precision, and force of a guitarist's left-hand. The overarching questions behind our study are: 1) Do unintentional actions originating from motor and biomechanical functions during musical performance contribute a material "human feel" to the performance? 2) Would it be possible determine and quantify such unintentional actions? 3) Would it be possible to model and embed such information in a computer system? The contributionst o knowledgep ursued in this thesis include: a) An unprecedented study of guitar mechanics, ergonomics, and playability; b) A detailed study of how the human body performs actions when playing the guitar; c) A methodologyt o formally record quantifiable data about such actionsin performance; d) An approach to model such information, and e) A demonstration of how the above knowledge can be embeddedin a system for music performance