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Project 5: Discrete Cosine Transform & Audio Compression

For the third problem, we will use the MDCT+windowing function from the previous problem to compress chords of multiple tones layered on top of one another. For the sake of demonstration, a basic C Major chord (C-E-G-C) will be compressed at different degrees of bit quanitzation.

Relevant files: prob2codec.m, question3.m, and prob3.txt.
\( b = 2 \)

\( b = 3 \)

\( b = 4 \)

\( b = 5 \)

\( b = 6 \)

\( b = 8 \)

As expected, higher values of \(b\) produce more accurate approximations. At \(b = 8\), next to no error can be heard. Plotting # of quantization bits vs RMSE shows a roughly logarithmic relationship, with each extra bit of precision cutting error roughly in half:

\(b\) 2 3 4 5 6 8
rmse 0.01449 0.00727 0.00378 0.00211 0.00115 0.00036
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