{"record":{"leader":"cx  r22     2  45","datafield":[{"ind2":" ","ind1":" ","subfield":{"code":"a","content":"20200708afrey50      ba0"},"tag":100},{"ind2":" ","ind1":" ","subfield":[{"code":"a","content":"eng"},{"code":2,"content":"639-2"}],"tag":101},{"ind2":" ","ind1":" ","subfield":{"code":"a","content":2007},"tag":103},{"ind2":" ","ind1":" ","subfield":[{"code":"a","content":"k"},{"code":"f","content":"fre"}],"tag":104},{"ind2":" ","ind1":" ","subfield":[{"code":"a","content":0},{"code":"b","content":"#"},{"code":"c","content":"#"}],"tag":106},{"ind2":" ","ind1":" ","subfield":{"code":"a","content":"AFNOR"},"tag":152},{"ind2":" ","ind1":" ","subfield":{"code":"a","content":"Oeuvre Textuelle"},"tag":189},{"ind2":" ","ind1":" ","subfield":[{"code":7,"content":"ba0yba0"},{"code":"t","content":"Model-based techniques for flexible speech and audio coding"}],"tag":241},{"ind2":" ","ind1":" ","subfield":[{"code":7,"content":"ba0yba0y"},{"code":"a","content":"L\u2019objectif de cette thèse est de développer des techniques de codage de parole et audio optimales et plus flexibles que avec l\u2019état de l\u2019art, pouvant s\u2019adapter en temps réel à différentes contraintes (débit, largeur de bande, retard). Cette problématique est étudiée à l\u2019aide de différents outils : modélisation statistique, théorie de la quantification à haut débit, codage entropique flexible. On propose d\u2019abord une nouvelle technique de codage flexible des coefficients de prédiction linéaire (LPC) combinant une transformée de Karhumen-Loeve (KLT) et une quantification scalaire basée sur un modèle gaussien généralisé. Les performances sont équivalentes à celle du quantificateur utilisé dans l\u2019AMR-WB. De plus la complexité est moindre. Puis, on propose deux techniques de codage audio par transformée flexible, l\u2019une utilisant le codage « stack-run » et l\u2019autre le codage par plans de bits basé modèle. Dans les deux cas, le signal après pondération perceptuelle et transformation discrète en cosinus modifié (MDCT) est modélisé par une distribution gaussienne généralisée qui sert à optimiser le codage. La qualité du codeur stack-run est meilleure que ITU-T G.722.1 à bas débit et équivalente à haut débit. Par contre, le codeur stack-run est plus complexe et son coût mémoire est faible. L\u2019avantage du codage par plans de bits est d\u2019être scalable en débit. Nous proposons d\u2019utiliser le modèle gaussien généralisé afin d\u2019initialiser les tables de probabilités du codage arithmétique utilise�� dans le codage par plan de bits. La qualité associée est inférieure à celle du codeur stack-run à bas débit et équivalente à haut débit. Par contre, la complexité de calcul est proche de G.722.1."}],"tag":300},{"ind2":" ","ind1":" ","subfield":[{"code":7,"content":"ba0yba0y"},{"code":"a","content":"The objective of this thesis is to develop optimal speech and audio coding techniques which are more flexible than the state of the art and can adapt in real-time to various constraints (rate, bandwidth, delay). This problem is addressed using several tools : statistical models, high-rate quantization theory, flexible entropy coding. Firstly, a novel method of flexible coding for linear prediction coding (LPC) coefficients is proposed using Karhunen-Loeve transform (KLT) and scalar quantization based on generalized Gaussian modelling. This method has a performance equivalent to the LPC quantizer used in AMR-WB with a lower complexity. Then, two transform audio coding structures are proposed using either stack-run coding or model-based bit plane coding. In both case the coefficients after perceptual weighting and modified discrete cosine transform (MDCT) are approximated by a generalized Gaussian distribution. The coding of MDCT coefficients is optimized according to this model. The performance is compared with that of ITU-T G.7222.1. The stack-run coder is better than G.7222.1 at low bit rates and equivalent at high bit rates. However, the computational complexity of the proposed stack-run coder is higher and the memory requirement is low. The bit plane coder has the advantage of being bit rate scalable. The generalized Gaussian model is used to initialize the probability tables of an arithmetic coder. The bit plane coder is worse than stack-run coding at low bit rates and equivalent at high bit rates. It has a computational complexity close to G.7222.1 while memory requirement is still low."}],"tag":300},{"ind2":0,"ind1":" ","subfield":[{"code":"b","content":"Thèse de doctorat"},{"code":"c","content":"Automatique, traitement du signal et des images"},{"code":"e","content":"Nice"},{"code":"d","content":2007}],"tag":328},{"ind2":" ","ind1":" ","subfield":[{"code":7,"content":"ba0yba0"},{"code":"t","content":"Model-based techniques for flexible speech and audio coding"}],"tag":441},{"ind2":1,"ind1":" ","subfield":[{"code":3,"content":136842240},{"code":7,"content":"ba0yba03"},{"code":"a","content":"Oger"},{"code":"b","content":"Marie"},{"code":"f","content":"1979-...."},{"code":4,"content":"070"}],"tag":501},{"ind2":1,"ind1":" ","subfield":[{"code":3,"content":"076368890"},{"code":7,"content":"ba0yba03"},{"code":"a","content":"Antonini"},{"code":"b","content":"Marc"},{"code":"f","content":"19..-...."},{"code":4,"content":727}],"tag":501},{"ind2":1,"ind1":" ","subfield":[{"code":3,"content":136843778},{"code":7,"content":"ba0yba03"},{"code":"a","content":"Ragot"},{"code":"b","content":"Stéphane"},{"code":"f","content":"19..-...."},{"code":4,"content":727}],"tag":501},{"ind2":2,"ind1":0,"subfield":[{"code":3,"content":"059079800"},{"code":7,"content":"ba0yba03"},{"code":"a","content":"École doctorale Sciences et technologies de l'information et de la communication"},{"code":"c","content":"Nice"},{"code":"c","content":"1992-...."},{"code":4,"content":996}],"tag":511},{"ind2":2,"ind1":0,"subfield":[{"code":3,"content":"026403498"},{"code":7,"content":"ba0yba03"},{"code":"a","content":"Université de Nice"},{"code":"c","content":"1965-2019"},{"code":4,"content":295}],"tag":511},{"ind2":2,"ind1":0,"subfield":[{"code":3,"content":"059078995"},{"code":7,"content":"ba0yba03"},{"code":"a","content":"Université de Nice-Sophia Antipolis"},{"code":"b","content":"Faculté des sciences"},{"code":4,"content":295}],"tag":511},{"ind2":" ","ind1":" ","subfield":[{"code":3,"content":"027245799"},{"code":"a","content":"Synthèse automatique de la parole"},{"code":2,"content":"rameau"}],"tag":606},{"ind2":" ","ind1":" ","subfield":[{"code":3,"content":"027282767"},{"code":"a","content":"Codage"},{"code":2,"content":"rameau"}],"tag":606},{"ind2":" ","ind1":" ","subfield":[{"code":3,"content":"027425118"},{"code":"a","content":"Processus gaussiens"},{"code":2,"content":"rameau"}],"tag":606},{"ind2":" ","ind1":" ","subfield":[{"code":3,"content":"027674134"},{"code":"a","content":"Modèles linéaires (statistique)"},{"code":2,"content":"rameau"}],"tag":606},{"ind2":" ","ind1":" ","subfield":[{"code":7,"content":"ba0yba0"},{"code":3,"content":"027253139"},{"code":"a","content":"Thèses et écrits académiques"},{"code":2,"content":"rameau"}],"tag":608},{"ind2":" ","ind1":" ","subfield":[{"code":"a","content":620},{"code":2,"content":"TEF"}],"tag":686},{"ind2":3,"ind1":" ","subfield":[{"code":"a","content":"FR"},{"code":"b","content":"Abes"},{"code":"c","content":20240529},{"code":"g","content":"AFNOR"}],"tag":801}],"controlfield":[{"tag":"001","content":247842818},{"tag":"003","content":"http://www.idref.fr/247842818"},{"tag":"004","content":20200708},{"tag":"005","content":20240529073201},{"tag":"006","content":"0499"},{"tag":"007","content":"0499"},{"tag":"008","content":"Tr2"}]}}