Hugo’s Status Report 2/15

Continuing on where I left off last week, this week I spent my time looking into the specific methods for implementing the system. Because I am our primary audio processing lead, my work revolved around fleshing out not only systems for vocal removal, but also how generally getting the full outline for how our data is being passed around and what kind of processing we need to do. First, after our proposal presentation, we had a slight change of path with regards to how we want to do scoring for our game. Originally, we had intended to work with pitch detection but now wanted to find something that more accurately captured the karaoke experience for the average user. We came up with a series of new metrics and strategies, and are continuing to analyze and pick a specific plan. Then, I took time to investigate the vocal removal aspect. Because this is currently such a fundamental part of the project it is imperative that this works as expected. I used matlab to do some tests by passing through audio files to see the effects of our original bandpass and bandstop filtering idea. In the end, this was not effective. Although the bandpass could kind of get a weak signal that almost isolated the vocal (often leaving in percussion), the bandstop filter was next to useless at removing the vocals from the backing track. So, I moved on to testing methods that take advantage of audio in stereo format to cancel out the vocals by subtracting the left and right channels. In the end, this did provide favorable results while still allowing us to work with a hardware system as we had originally hoped. Then I took time to read into the actual wiring and built up a design for splitting the two audio channels, passing through our subtractor, adding in the microphone input, and outputting to a speaker. I also took some time to look at possible speaker options and assessed whether this was a part that we wanted to allocate substantial amount of the budget to, as it is crucial that the sound quality is high for the product to reach our user requirements.