|
发表于 2009-8-27 17:27:22
|
显示全部楼层
论坛年底应该给楼主发个奖章什么的
这个问题讨论到今天还以这种方法继续的话是不会有结果的。在我看来只有寻求第三方权威的解答。
What Hi-Fi 和 Stereophile 什么时候有答复还不知道。人家声明没有资源和义务一一答复所有来信。
这是美国斯坦福大学去年冬季 Perceptual Audio Coding 项目的一小段文档,里面简单介绍了标准WAV文件的结构组成和分析方法。
http://ccrma.stanford.edu/courses/422/projects/WaveFormat/
既然2个WAV文件开头不一样,楼主可以以它为参照,完整比较一下2个文件的差异。
如果分析结果是两个文件内容一致,那请看下面内容:
Perceptual Audio Coding 项目去年是由 Marina Bosi 教授带领的。引用该教授的课程 handbook 内容如下:
The need for significant reduction in data rate for wide-band digital audio signal transmission and storage has led to the development of psychoacoustics-based data compression techniques. In this approach, the limitations of human hearing are exploited to remove inaudible components of audio signals. The degree of bit rate reduction achievable without sacrificing perceived quality using these methods greatly exceeds that possible using lossless techniques alone. Perceptual audio coders are currently used in many applications including Digital Radio and Television, Digital Sound on Film, Multimedia/Internet Audio, and Electronic Music Distribution (EMD).
In this course, the basic principles of perceptual audio coding will be reviewed. State-of-the-art audio coding schemes, e.g. AC-3; MPEG Layers I, II, and III (MP3); MPEG AAC; MPEG-4, will be presented. In-class demonstrations will allow students to hear the quality of state-of-the-art implementations at varying data rates and they will be required to program their own simple perceptual audio coder during the course.
课程推荐读物 M. Bosi and R. Goldberg, "Introduction to Digital Audio Coding and Standards", Klewer Academic Publishers 2003.
由此可见,Marina Bosi 教授肯定了人耳有听力上限,并且有实验环境验证这一切,算是能够给出权威答复的人选。
楼主这么执着这一问题,可以联系一下这位教授。以美国斯坦福大学的资源,验证这两个WAV文件是否有音质差异是不在话下的。 |
|