Add Matlab script for converting LTV files in the long test vector branch to...

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% This script creates 16 kHz and 32 kHz versions of all wav-files in the

% same folder. This assumes that the input file will contain ltv48 as the

% starting pattern. It will replace them with ltv16 or ltv32 in the result.

%

% Note, MASA metadata and ISM metadata will not be converted as the same

% metadata can be used with lower sample rates.

d = dir('ltv48*.wav');

for n = 1:length(d)

    filename = d(n).name;

    disp(['Processing input file: ', filename]);

    [x, fs] = audioread(filename);

    if fs ~= 48000

        error('Input file is not with 48 kHz sample rate. Aborting.');

    end

    % Process 32 kHz

    x32 = resample(x, 32000, 48000);

    % Check if clipping would occur and normalize when necessary

    maxAbsVal = max(abs(x32),[],'all');

    if (maxAbsVal >= 1.0)

        warning('Clipping would occur, normalizing output');

        x32 = x32 .* (0.98/maxAbsVal);

    end

    audiowrite(['ltv32', filename(6:end)], x32, 32000);

    % Process 16 kHz

    x16 = resample(x, 16000, 48000);

    % Check if clipping would occur and normalize when necessary

    maxAbsVal = max(abs(x16),[],'all');

    if (maxAbsVal >= 1.0)

        warning('Clipping would occur, normalizing output');

        x16 = x16 .* (0.98/maxAbsVal);

    end

    audiowrite(['ltv16', filename(6:end)], x16, 16000);

end