主页：https://ccrma.stanford.edu/~scottl/thesis.html
题目：Audio Representations for Data Compression and Compressed Domain Processing
Following are some sound (*.wav) examples referred to in Appendix A of the thesis. In this set of sound examples, the sines+transients+noise compression scheme at 32 kbps/ch described in the thesis is compared to MPEG-AAC also at 32 kbps/ch. The MPEG-AAC examples were encoded using source code from FhG during October 1998.
- Original version of Mozart's Le Nozze di Figaro
- Figaro, compressed using MPEG-AAC at 32 kbps
- Figaro, compressed using sines+transients+noise as described in the thesis at 32 kbps
The individual sines, transients, and noise components from the previous sound file are shown separately.
- Figaro, just multiresolution sinusoids
- Figaro, just residual Bark-band noise
- Figaro, just transform-coded transients
- Figaro, just high frequency Bark-band noise
The next set of sound examples shows another comparison of between the thesis, sines+transients+noise system versus MPEG-AAC, but this time a pop piece is used instead.
- Original version of It Takes Two by Rob Base & DJ E-Z Rock
- It Takes Two, compressed using MPEG-AAC at 32 kbps
- It Takes Two, compressed using sines+transients+noise as described in the thesis at 32 kbps
The individual sines, transients, and noise components from the previous sound file are shown separately.
- It Takes Two, just multiresolution sinusoids
- It Takes Two, just residual Bark-band noise
- It Takes Two, just transform-coded transients
- It Takes Two, just high frequency Bark-band noise
The next several examples show the ability to perform pitch and time-scale modifications in the compressed domain. That is, while the audio is being decoded, it is also being time and/or pitch scaled. There is no need for external post-processing modification algorithms. All the following examples use the pop example, It Takes Two. The first two examples show the sound quality difference in slowing down music using the quantized sines+transients+noise system in this thesis versus the quality from commerically available software, Cool Edit.
- It Takes Two, time-scale modified two times slower using sines+transients+noise
- It Takes Two, time-scale modified two times slower using commercially available CoolEdit
- It Takes Two, time-scale modified using sines+transients+noise, looped using various time-scaling rates, from {2.0, 1.6, 1.2, 1.0, 0.8, 0.6, 0.5}
- It Takes Two, pitch-scale modified using sines+transients+noise, looped using various pitch-scaling rates, from {0.89, 0.94, 1.00, 1.06, 1.12}
This URL: http://www-ccrma.stanford.edu/~scottl/thesis.html
Last modified: December 3, 1998
Author: Scott Levine