Processing Audio

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Audio Files
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Yesterday I began looking at the audio files that I had collected a few weeks ago.

In my original audio recordings, I had two sessions.  While post processing these I originally normalized the volume on an utterance-by-utterance basis.  Of course, for my purposes, this is incorrect as it throws out all of the relativistic intensity values that we might utilize.  So I had to go back to the original two recordings, sound-normalize those and then chunk them into individual wave files again.

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Resynthesis Code
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I also worked with the code a bit.  The code for duration and pitch resythensis is complete but I am still trying to figure out what the output should be.  By that I mean, we started with utterance vs word level resythensis.  Today I tried phone level resynthensis.  It was brought on by a particular issue with 'bobby'.  In one broad production it came out something like [bavi] however, the [v] was not particularly salient--until I synthesized it into the contrastive focus context.

I thought that this was an artefact of the resynthesis code but it is not.  This became apparent when I tried phone-level resynthesis.  The phone-level resynthesis is only working for duration.  Because in pitch resynthesis we sample a constant number of points per sample region (something that should be changed anyways) phone-level resynthesis may not work for pitch.  We should instead to change from a set number of samples to time-based sampling.

(As an aside, it is interesting how one particular variant of a consonant ([v] for /b/) is perceived in a focused vs broad condition.  Also, it is interesting how there are pops and clicks in our speech that we don't even notice.  In all of my productions of "Bobby" there is a click half-way through that I cannot hear when I produce it (unless I am simply unable to reproduce it now?).  I'm not sure where it comes from.)

I don't think this issue is worth dealing with now, so for this first experiment we won't worry about phone-level resynthesis.  The question remains as to what to do for duration.

Next, my job is to select the audio stimuli that I will use in the experiment, generate word and phone-level textgrids, and create the hypothetical stimuli for use in this experiment.

First Post on Perception of Prominence Correlates

Since this is my first post on the matter I'll briefly explain the purpose of the project which I am titling 'Perception of Prominence Correlates'.  The goal is to see what acoustic values exactly drive perception of meaning-based acoustically marked words in an utterance.  Specifically, I am looking at words in subject position in contrastive focus vs. broad focus.  E.g. the response "Did Mary see the movie" and response "No, *John* saw the movie" vs. "What happened yesterday" "*John* saw the movie".  Where in the first case John is acoustically marked--the word may be uttered with more acoustic intensity, longer, and with a sharper or higher pitch accent than in the second situation.

To do this task, I collect these two responses and iteratively resynthesize the contrastive condition to be like the broad condition.  I am able to do this with word duration and the pitch contour (both of which, I am still fine-tuning) however, I don't have a good way to do this for intensity.  I may try some things if I have time but otherwise the experiment will be run without those.  I am using LMEDS to run this experiment.

From this experiment, broadly speaking, I hope to find out what triggers the perception of contrastive focus.  What drives perception?  Are the cue thresholds (largely) consistent within a person?  Across people?