I am about to present my work that I have created in MATLAB, but I am having trouble manipulating my data into a presentable form using the plot function.
My code looks like this:
[inputname, pathname] = uigetfile('*.wav', 'Select WAV-file');
thumb1 = inputname; %# Get filename information
fprintf('\n%s is being turned into a 30s thumbnail...\n', thumb1);
fprintf('Please wait..!\n\n');
%# load the signal
[y, fs, nb] = wavread(thumb1);
y = mean(y,2); %# stereo, take avrg of 2 channels
%# Calculate frame energy
fWidth = round(fs*10e-3); %# 10ms
numFrames = floor(length(y)/fWidth);
energy = zeros(1,numFrames);
for f=1:numFrames
energy(f) = sum( y((f-1)*fWidth+1:f*fWidth).^2 );
end
Basically I want to plot the energy of the track over time (in seconds).
plot(energy)
nearly does what I require, but I have an unusual amount of blank space at the end of the track which is not present in the .wav file
. This blank space is the main issue that I’m having. Ideally I would like the x axis to be displayed in seconds! Any help would be much appreciated.
edit1:
Using the first suggested method:
There’s also
which sets “tight” limits for the axis. See doc: http://www.mathworks.com/help/techdoc/ref/axis.html