Hi Joshua,
First, sorry we had a local funtion name with the same name as a function we ship. We are fixing this.
The function you copied and you're working off does not do well when the audio has multiple channels (for example, stereo). I suspect this is why you are seeing this error. If you only care about one channel, you can use indexing to just use the first channel of the audio. If you care about all channels, use this code instead (it uses the documented vggishPreprocess function. Make sure you do not have local function with that name around):
function [predictor,response,segmentsPerFile] = vggishPreprocessDatastore(ads,overlap)
% Preallocate cell arrays for the predictors and responses
numFiles = numel(ads.Files);
predictor = cell(numFiles,1);
response = predictor;
segmentsPerFile = zeros(numFiles,1);
% Extract predictors and responses for each file
for ii = 1:numFiles
[audioIn,info] = read(ads);
duration = size(audioIn,1)/info.SampleRate;
if duration>=0.975
% Use the documented vggishPreprocess function
predictor{ii} = vggishPreprocess(audioIn,info.SampleRate,"OverlapPercentage",overlap);
numHops = size(predictor{ii},4);
response{ii} = repelem(info.Label,numHops);
segmentsPerFile(ii) = numHops;
else % signal too short - no results
predictor{ii} = [];
response{ii} = [];
segmentsPerFile(ii)=0;
end
end
% Concatenate predictors and responses into arrays
predictor = cat(4,predictor{:});
response = cat(2,response{:});
end
