Kể từ khi MPEG-7 cung cấp một khuôn khổ thành lập với một tập lớn các mô tả, tiêu chuẩn được sử dụng như là một ví dụ để minh họa cho khái niệm. Các định nghĩa toán học của tất cả các định dạng MPEG-7 mô tả âm thanh ở mức độ thấp được vạch ra chi tiết. | ORGANIZATION OF THE BOOK 11 The purpose of Chapter 2 is to provide the reader with a detailed overview of low-level audio descriptors. To a large extent this chapter provides the foundations and definitions for most of the remaining chapters of the book. Since MPEG-7 provides an established framework with a large set of descriptors the standard is used as an example to illustrate the concept. The mathematical definitions of all MPEG-7 low-level audio descriptors are outlined in detail. Other established low-level descriptors beyond MPEG-7 are introduced. To help the reader visualize the kind of information that these descriptors convey some experimental results are given to illustrate the definitions. In Chapter 3 the reader is introduced to the concepts of sound similarity and sound classification. Various classifiers and their properties are discussed. Low-level descriptors introduced in the previous chapter are employed for illustration. The MPEG-7 standard is again used as a starting point to explain the practical implementation of sound classification systems. The performance of MPEG-7 systems is compared with the well-established MFCC feature extraction method. The chapter provides in great detail simulation results of various systems for sound classification. Chapter 4 focuses on MPEG-7 SpokenContent description. It is possible to follow most of the chapter without reading the other parts of the book. The primary goal is to provide the reader with a detailed overview of ASR and its use for MPEG-7 SpokenContent description. The structure of the MPEG-7 SpokenContent description itself is presented in detail and discussed in the context of the spoken document retrieval SDR application. The contribution of the MPEG-7 SpokenContent tool to the standardization and development of future SDR applications is emphasized. Many application examples and experimental results are provided to illustrate the concept. Music description tools for specifying the properties
