When someone wishes to find the lyrics for a song they typically go online and use a search engine. There are a large number of lyrics available on the internet as the effort required to transcribe and post lyrics is minimal. These lyrics are promptly returned to the user with customary search engine page ranking formula deciding the ordering of these results based on links, views, clicks, etc. However the content, and specifically, the accuracy of the lyrics in question are not analysed or used in any way to determine the rank of the lyrics, despite this being of concern to the searcher. In this work, we show that online lyrics are often inaccurate and the ranking methods used by search engines do not distinguish the more accurate annotations. We present an alternative method for ranking lyrics based purely on the collection of lyrics themselves using the Lyrics Concurrence.

With the constant improvements in the technical capabilities and bandwidth available to mobile phones, mobile audio and video streaming services are booming. This allows music enthusiasts to watch their favourite music videos instead of only listening to the audio tracks, thus augmenting their listening experience to be multimodal. Usually the highly compressed audio tracks in these videos result in poorer quality music, compared to music the user might already have locally on their phone or playing through another sound source. In this paper we present MuViSync Mobile, a mobile phone application that synchronises real-time high quality music, either stored locally or input through the microphone, with the corresponding streaming music video. We extend previous work on music to music video synchronisation by proposing an alternative algorithm for higher efficiency with similar alignment accuracy, which we tested with music video examples including simulated noise. This algorithm correctly aligns 90% of the audio frames to within 100 ms of the known alignment. We also describe its implementation on an iPhone.

With over 4.5 million tablatures and chord sequences (collectively known as tabs), the web holds vast quantities of hand annotated scores in non-standardised text files. These scores are typically error-prone and incomplete, and tab collections contain many duplicates, making retrieval of high quality tabs difficult. Despite this, tabs are by far the most popular means of sharing musical instructions on the internet. We have developed tools that use text analysis and alignment for the automatic retrieval, interpretation and analysis of such tabs in order to filter and estimate the most accurate tabs from the multitude available. We show that the standard means of ranking tabs, such as search engine ranks or user ratings, have little correlation with the accuracy of a tab and that a better ranking method is to use features such as the concurrency between tabs of the same song. We also compare the quality of top-ranked tabs with state-of-the-art chord transcription output and find that the latter provides a more reliable source of chord symbols with an accuracy rate 10% higher than the ranked hand annotations.

Music recommendation systems built on top of music information retrieval (MIR) technologies are usually designed to provide new ways to discover and listen to digital music collections. However, they do not typically assist in another important aspect of musical activity, music learning. In this study we present the application Hotttabs, an online music recommendation system dedicated to guitar learning. Hotttabs makes use of The Echo Nest music platform to retrieve the latest popular or hot songs based on editorial, social and charts/sales criteria, and YouTube to find relevant guitar video tutorials. The audio tracks of the YouTube videos are processed with an automatic chord extraction algorithm in order to provide a visual feedback of the chord labels synchronised with the video. Guitar tablatures, a form of music notation showing instrument fingerings, are mined from the web and their chord sequences are extracted. The tablatures are then clustered based on the songs' chord sequences complexity so that guitarists can pick up those adapted to their performance skills.

Dynamic Time Warping (DTW) is used to find alignments between two related streams of information and can be used to link data, recognise patterns or find similarities. Typically, DTW requires the complete series of both input streams in advance and has quadratic time and space requirements. As such DTW is unsuitable for real-time applications and is inefficient for aligning long sequences. We present Windowed Time Warping (WTW), a variation on DTW that, by dividing the path into a series of DTW windows and making use of path cost estimation, achieves alignments with an accuracy and efficiency superior to other leading modifications and with the capability of synchronising in real-time. We demonstrate this method in a score following application. Evaluation of the WTW score following system found 97.0% of audio note onsets were correctly aligned within 2000 ms of the known time. Results also show reductions in execution times over state-of-theart efficient DTW modifications.

Although guitar tablature is the most prevalent musical score format on the internet, score following programs are only made for traditional musical scores or MIDI. The following work demonstrates a score following method for guitar tablature (tabs). In this method, a guitar tab parser interprets the score from HTML or ASCII text tabs which is then synthesised with guitar-like parameters. Finally, real-time audio to audio synchronisation methods are then used to accurately track the musicians position within the tab. A prototype application has been made to demonstrate this technique.

Before the advent of Hidden Markov Models(HMM)-based speech recognition, many speech applications were built using pattern matching algorithms like the Dynamic Time Warping (DTW) algorithm, which are generally robust to noise and easy to implement. The standard DTW algorithm usually suffers from lack of flexibility on start-end matching points and has high computational costs. Although some DTW-based algorithms have been proposed over the years to solve either one of these problems, none is able to discover multiple alignment paths with low computational costs. In this paper, we present an “unbounded” version on the DTW (U-DTW in short) that is computationally lightweight and allows for total flexibility on where the matching segment occurs. Results on a word matching database show very competitive performances both in accuracy and processing time compared to existing alternatives.

In recent years, the popularity of compressed music files and online music downloads has increased dramatically. Today's users own large digital collections of high quality music on their computers and portable devices to be played in their homes or on the go. In addition, music videos are being offered online both for free and through monthly subscriptions, opening up the opportunity to turn the music listening activity into a multimedia experience. The work presented in this paper addresses the challenge of music audio and music video synchronisation. In particular, we have developed a prototype, named MuViSync, to automatically synchronise music videos to the songs that users are listening to in real-time. At the core of the MuViSync prototype are novel audio synchronization algorithms to tackle the differences in tempo, pitch, sampling rates, structure, and introductions and endings that are common in the various digital recordings of the same song in modern music. The music and the music video are initially aligned and then kept in sync within the limits of human perception. In experiments with 320 matching pairs of audio files and music videos, the proposed algorithms successfully synchronise music and video to within 100 milliseconds of each other in over 90% of the cases.

The computer games industry has recently been producing titles in a new genre called ‘music’ that toys with engaging the user in musical expression. The technology used in these games has allowed for novel interfaces for representing musical instructions which has yet to be tried within musical practice and tuition. The games themselves have greatly simplified the instruments and the music created to the point where the skills learnt are not transferrable to the actual instruments that they seek to recreate. The aim of this work is to explore the potential to move from this category of entertainment systems based on musical expression towards tutoring applications that support learning musical instruments in an entertaining and rewarding experience. Note-Scroller (Figure 1) is an interface that has been designed to bridge this gap and act as a case study for evaluating the potential of such a movement. It is hoped that Note-Scroller will be fun and intuitive to use, teaching users how to play music on a piano-style keyboard.

Changes in the molecular weight distribution of components in green coffee during roasting were investigated using high performance gel filtration chromatography (HPGFC) with TSK-PW 4000 columns. The chromatographic separation of sample extracts obtained from green and roasted coffees, after different degrees of roasting, was monitored by refractive index (RI) detection and UV detection at 280, 325 and 420 nm. The chromatograms obtained with RI detection showed significant differences in molecular weight profiles. UV detection showed similar patterns at 280 and 325 nm, suggesting that phenolic compounds were probably bound to proteins. The formation of pigments was clearly demonstrated when chromatography was carried out with detection at 420 nm and the coloured material was found to be distributed throughout the molecular weight range studied. The use of HPGFC provided a more rapid analysis compared with traditional gel filtration and proved to be useful in monitoring changes in molecular weight which occur during coffee roasting.

A comparative assessment of HPLC methods for vitamin analysis was designed in which a number of institutions were asked to carry out the determination of ascorbic acid and thiamin in three samples (1, a mixture of thiamin and ascorbic acid in glucose; and 2 and 3, fortified breakfast cereals). Coefficients of variation between laboratories for sample 1 (ascorbic acid 5.6 and thiamin 6.9%) were much lower than for samples 2 and 3 (ascorbic acid 23 and 19% and thiamin 47 and 34%, respectively), the latter being considerably greater than is desirable. It is concluded that HPLC will not become a widely accepted technique for the determination of vitamins in foods until all the stages of the analysis, including extraction, clean-up and HPLC, are thoroughly validated.

A method, based on high-performance liquid chromatography, is described for the determination of chlorogenic acid isomers in instant coffee. Identification of the individual components was assisted by the preparation of isomeric mixtures by the isomerisation of available compounds and quantification based on published ultraviolet molar absorptivities. A number of extraction and clearing techniques were studied to determine the optimum conditions for the recovery of all the isomers present. The developed method was applied to a wide range of commercially available instant coffees.

AbstractA simple, rapid high performance liquid chromatography method is reported for the simultaneous analysis of trigonelline and caffeine (1,3,7‐trimethylxanthine) in coffee, and theobromine (3,7‐dimethylxanthine) and caffeine in samples of cocoa, drinking chocolate, tea and cola. Chromatography was carried out on Spherisorb‐ODS columns with gradient elution. The eluate was monitored at 272 nm with an ultraviolet spectrophotometer and quantification was achieved with external standards. Results for different brands of instant coffees, one decaffeinated coffee, and for samples of cocoa, drinking chocolate, tea and cola are reported.

Chemischer InformationsdienstVolume 6, Issue 41 Natural Products ChemInform Abstract: AMINO-ACIDS AND PEPTIDES PART 38, USE OF 4-PICOLYLOXYCARBONYLHYDRAZIDES AS HANDLES TO FACILITATE PEPTIDE SYNTHESIS, SYNTHESIS OF FRAGMENTS RELATED TO PORCINE GASTRIC INHIBITORY POLYPEPTIDE ROBERT MACRAE, ROBERT MACRAESearch for more papers by this authorGEOFFREY T. YOUNG, GEOFFREY T. YOUNGSearch for more papers by this author ROBERT MACRAE, ROBERT MACRAESearch for more papers by this authorGEOFFREY T. YOUNG, GEOFFREY T. YOUNGSearch for more papers by this author First published: October 14, 1975 https://doi.org/10.1002/chin.197541392AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume6, Issue41October 14, 1975 RelatedInformation

The use of the 4-picolyloxycarbonylhydrazide (4-pyridylmethoxycarbonylhydrazide) of the carboxy-terminal amino-acid provides both protection of the hydrazide group during peptide synthesis and a weakly basic ‘handle’ by which the product can readily be isolated after each coupling reaction. The procedure is illustrated by the synthesis of t-butoxycarbonyl-L-leucyl-L-alanylglycyl-L-valine hydrazide (5) and of the 4-picolyloxycarbonylhydrazides of a number of fragments related to the N-terminal sequence of porcine gastric inhibitory polypeptide. The 4-picolyloxycarbonyl group was removed by catalytic hydrogenolysis and by electrolytic reduction. The 4-picolyloxycarbonylhydrazides of eight-t-butoxycarbonylamino-acids are described.