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#include <stdio.h>
#include <stdlib.h>
#include <alsa/asoundlib.h>
      
#define BUF_BYTES 128

int main (int argc, char *argv[]) {
    int err;
    unsigned char buf[BUF_BYTES];
    

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function segs = get_segments(o)

segs = [];

if o(1), st = 1; state = 1;
else state = 2; end

for i = 2 : length(o)
    if o(i)
        if state == 2

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function mkdir_if_not_exist(dirpath)
    if dirpath(end) ~= '/', dirpath = [dirpath '/']; end
    if (exist(dirpath, 'dir') == 0), mkdir(dirpath); end
end

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function [ao, bo, offset, y] = align(a, b)
% align two signals a and b
% ao and bo are aligned ones with same length
% y is the correlation xcorr(a, b)
% a_ind + offset -> b_ind
% if offset >= 0, cut a, else cut b

an = length(a); bn = length(b);

N = max(an, bn);

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function t = get_threshold(v)
% pitch the lowest 20% 

[m, inds] = sort(v);

P = fix(0.2 * length(v));
nt = m(P);

P = fix(0.8 * length(v));
nt2 = m(P);

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function val = init_option(options, name, default_val)
% usage lamda = init_option(options, 'lamda', 0.01);
    if isfield(options, name), val = options.(name); else val = default_val; end
end

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function [I, J, xvals] = get_local_maxima(imcor, radius)
% a = rand(10);
% [I, J, xvals] = get_local_maxima(a, 3);
% figure, imagesc(a); hold on; scatter(J, I);

[m, n] = size(imcor);
nim = ones(m + radius * 2, n + radius * 2) * 1e-10;
nim(radius + (1:m), radius + (1:n)) = imcor;

cols = im2col(nim, [2*radius + 1, 2 * radius + 1], 'sliding');

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int nextpow2 (int x) {
    if (x < 0)
        return 0;
    --x;
    x |= x >> 1;
    x |= x >> 2;
    x |= x >> 4;
    x |= x >> 8;
    x |= x >> 16;
    return x+1;

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# given a directory or a set of files
# concatenate the binary files
# output a single binary file

# usage:
# ruby concatenate_binary_files "/xxx/xx/*.bin" "/xxx/xx.bin"

infiles = ARGV[0]
outpath = ARGV[1]
File.open(outpath, 'wb') do |outfile|

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#include "mex.h"
// undef needed for LCC compiler
#undef EXTERN_C

// mex mex_show_sparse.cpp -O -largeArrayDims
// a = sparse(rand(10)<0.1)
// mex_show_sparse(a);
// b = a .* rand(10)
// mex_show_sparse(b);
void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[]) {