Status Report #11: (12/7) Eugene

  • Finished up our final design report
  • Tested directional microphone, which doesn’t have correct driver configurations to let us read in and output sound
  • Tested HomePod, which is much more resilient to our exploit. We chalk this up to a much more robust system of speakers designed to more effectively parse out sound than a low-power, single-mic, always-on system.

Status Report #10: (11/30) Spencer

  • Met with Prof. Stern wrt how to proceed in our attack
  • Rewrote Matlab version of attack code
  • Finished various dtw + mfcc implementations
    • Constantly polling in 30ms frames vs. triggering only at a given threshold
    • DTW incorporation causes much lower false positive rate. Can play music or some verbal sounds without triggering automatically, which is far better than our midpoint demo.
    • Seems a little bit too slow running in practice for jamming an iPhone. Could be due to my hardware being older than Eugene’s since the attack seems to work on his computer.

Status Report #9: (11/23) Cyrus

  • Met with Stern on Wednesday to try to fix issues with our MFCC + DTW code.
  • The librosa library we were using in Python does not provide enough options for tweaking the algorithm to our specific application, and hence we decided to switch to MATLAB after a second meeting with Professor Stern.
  • Verification of our algorithm requires the use of spectrograms, and we are currently having trouble replicating spectrograms in MATLAB for audio samples whose spectrograms are already known.


Status Report #9: (11/23) Spencer

  • Met with Prof. Stern multiple times to try resolving the issues we had with our pipeline.
  • Verification of our results with the Librosa MFCC + FastDTW chain is difficult due to the untransparent nature of the code.
  • We switched to Matlab to try making a more transparent, verifiable, and well supported pipeline.
  • Currently we are having trouble creating spectrograms that verify the results that we care about – the warped data should have a similar spectrogram to the reference sample to be warped, with the utterances in the same locations.
  • Will continue to explore fixes with this pipeline.

Status Report #9: (11/23) Eugene

  • After meeting with Stern on Wednesday, I spent time trying to apply DTW to MFCC coefficients to identify how to map between two signals. Initial results proved unfruitful.
  • Following Spencer’s and Cyrus’ meeting with Stern on Friday, I tried to re-implement our code in MATLAB for more robust tools, and more support + documentation.
  • Barring installation errors with MATLAB, we are currently blocked on interpreting spectrogram results so will need to meet with Stern (again) to resolve.