1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
|
// Copyright (C) 2018 - IIT Bombay - FOSSEE
//
// This file must be used under the terms of the CeCILL.
// This source file is licensed as described in the file COPYING, which
// you should have received as part of this distribution. The terms
// are also available at
// http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt
// Author:[insert name]
// Organization: FOSSEE, IIT Bombay
// Email: toolbox@scilab.in
//Function y=upfirdn(xin,h,p,q)
//
//this function upsamples the input data xin by factor "p", filters it using fiter coefficients "h" and the downsamples this filtered data by a factor "q".
//Esentially it is a cascade of three processes:
//1)Upsampling(Interpolation)
//2)Filtering
//3)Downsampling(Decimation)
//Test cases:
//1.yout=upfirdn (1:100, 1, 1, 1)
//Expected output: yout=1:100
//2.yout=upfirdn (1:100, 1, 1, 2)
//Expected outut: yout=1:2:100
function yout = upfirdn(xin,h,p,q)
[nargout,nargin]=argn();
if(nargin < 2)
error("usage : yout = upfirdn(xin,h,p,q)");
end
if(nargin < 3)
p = 1;
q = 1;
end
if(nargin < 4)
q = 1;
end
if(floor(p) ~= p | floor(q) ~= q | p < 1 | q < 1)
error('p and q must be positive integer');
end
yout = upsample(xin,p);
yout = filter(h,1,yout);
yout = downsample(yout,q);
endfunction
|
