Beat This

A Beat Synchronization Project
Kileen Cheng Bobak Nazer Jyoti Uppuluri Ryan Verret


Beat Detection Algorithm

Frequency Filterbank
Comb Filter

Block Diagram

Matlab Code
Matlab Plots

Time Scaling Algorithm

Matlab Code


Phase Alignment Algorithm

Matlab Code
Matlab Plots



Music Samples






About The Gang


You Are Visitor

  Time Scaling Algorithm

 The second most important goal of our project was to scale the time of the signal while maintaining the same pitch. There are a variety of methods to accomplish this task, some significantly more complex than others. The method that we chose was fairly simple and easy to implement. The results were consistently better when we chose to speed up signals rather than slow them down. This was accomplished by removing samples in such a way as to not perceptively change the audible frequencies. Blocks of samples were deleted every 80 ms which corresponds to a frequency of 12.5 Hz. Since the human ear cannot detect changes below 20 Hz, this did not change any frequencies that affected the sound quality. It did, however, produce very brief interruptions in the signal, but were not noticeable when combined with another signal in the final step.

  Matlab Code

  • timescale.m - scales the length of a singal to compression times its % original length, where compression is less than one.



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