Problem 1
Contents
Record Audio
r = audiorecorder(16000,16,1); recordblocking(r,2) recspeech = getaudiodata(r,'double'); %figure(1) %plot(recspeech)
Parts a, b, and c
[speech Fs] = wavread('PatOKeefe'); t = 0:1/Fs:length(speech)/Fs-1/Fs; figure(1) subplot(311) plot(t,speech) narrow_N = round(.02*Fs); narrow_OL = round(0.97*narrow_N); wideband_N = round(narrow_N/4); wideband_OL = round(0.9*wideband_N); subplot(312) spectrogram(speech,narrow_N,narrow_OL,0:100:8000,Fs,'yaxis'); title('Narrowband'); subplot(313) spectrogram(speech,wideband_N,wideband_OL,0:100:8000,Fs,'yaxis'); title('Wideband');
Part d
length_30ms = round(.03*Fs); % find appropriate sample start positions vowelOneStartSample = round(0.29*Fs); vowelTwoStartSample =round(1.14*Fs); % isolate 30ms of interest for both vowels wave1 = speech(vowelOneStartSample:vowelOneStartSample+length_30ms); wave2 = speech(vowelTwoStartSample:vowelTwoStartSample+length_30ms); waveOne = wave1*hamming(length(wave1))'; waveTwo = wave2*hamming(length(wave2))'; % find the transform of the two segments WAVEONE = fft(waveOne,2^nextpow2(waveOne)); WAVETWO = fft(waveTwo,2^nextpow2(waveTwo)); W1_Mag = 20*log10(abs(WAVEONE)); W2_Mag = 20*log10(abs(WAVETWO)); W1_Phase = unwrap(angle(WAVEONE)); W2_Phase = unwrap(angle(WAVETWO)); figure(1) subplot(311) plot(linspace(vowelOneStartSample/Fs,vowelOneStartSample/Fs+.03,length(wave1)),wave1); axis tight,grid on title('Waveform for /@/'),xlabel('Time (sec)'),ylabel('Amplitude'); subplot(312) plot(linspace(0,Fs/2,length(W1_Mag)/2),W1_Mag(1:length(W1_Mag)/2)); axis tight,grid on title('Magnitude Spectrum'),xlabel('Frequency (Hz)'),ylabel('Magnitude (dB)'); subplot(313) plot(linspace(0,Fs/2,length(W1_Phase)/2),W1_Phase(1:length(W1_Phase)/2)) axis tight,grid on title('Phase Spectrum'),xlabel('Frequency (Hz)'),ylabel('Radius'); figure(2) subplot(311) plot(linspace(vowelTwoStartSample/Fs,vowelTwoStartSample/Fs+.03,length(wave2)),wave2); axis tight,grid on title('Waveform for /o/'),xlabel('Time (sec)'),ylabel('Amplitude'); subplot(312) plot(linspace(0,Fs/2,length(W2_Mag)/2),W2_Mag(1:length(W2_Mag)/2)); axis tight,grid on title('Magnitude Spectrum'),xlabel('Frequency (Hz)'),ylabel('Magnitude (dB)'); subplot(313) plot(linspace(0,Fs/2,length(W2_Phase)/2),W2_Phase(1:length(W2_Phase)/2)) axis tight,grid on title('Phase Spectrum'),xlabel('Frequency (Hz)'),ylabel('Radius');
