--- /dev/null
+## Copyright (C) 2004 Josep Mones i Teixidor
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 2 of the License, or
+## (at your option) any later version.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+## GNU General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program; If not, see <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {@var{B} = } padarray (@var{A},@var{padsize})
+## @deftypefnx {Function File} {@var{B} = } padarray (@var{A},@var{padsize},@var{padval})
+## @deftypefnx {Function File} {@var{B} = } padarray (@var{A},@var{padsize},@var{padval},@var{direction})
+## Pads an array in a configurable way.
+##
+## B = padarray(A,padsize) pads an array @var{A} with zeros, where
+## @var{padsize} defines the amount of padding to add in each dimension
+## (it must be a vector of positive integers).
+##
+## Each component of @var{padsize} defines the number of elements of
+## padding that will be added in the corresponding dimension. For
+## instance, [4,5] adds 4 elements of padding in first dimension (vertical)
+## and 5 in second dimension (horizontal).
+##
+## B = padarray(A,padsize,padval) pads @var{A} using the value specified
+## by @var{padval}. @var{padval} can be a scalar or a string. Possible
+## values are:
+##
+## @table @asis
+## @item 0
+## Pads with 0 as described above. This is the default behaviour.
+## @item Scalar
+## Pads using @var{padval} as a padding value.
+## @item "Circular"
+## Pads with a circular repetition of elements in @var{A} (similar to
+## tiling @var{A}).
+## @item "Replicate"
+## Pads replicating values of @var{A} which are at the border of the
+## array.
+## @item "Symmetric"
+## Pads with a mirror reflection of @var{A}.
+## @item "Reflect"
+## Same as "symmetric", but the borders are not used in the padding.
+## @end table
+##
+## B = padarray(A,padsize,padval,direction) pads @var{A} defining the
+## direction of the pad. Possible values are:
+##
+## @table @asis
+## @item "Both"
+## For each dimension it pads before the first element the number
+## of elements defined by @var{padsize} and the same number again after
+## the last element. This is the default value.
+## @item "Pre"
+## For each dimension it pads before the first element the number of
+## elements defined by @var{padsize}.
+## @item "Post"
+## For each dimension it pads after the last element the number of
+## elements defined by @var{padsize}.
+## @end table
+## @end deftypefn
+
+## Author: Josep Mones i Teixidor <jmones@puntbarra.com>
+
+function B = padarray(A, padsize, padval = 0, direction = "both")
+ # Check parameters
+ if (nargin < 2 || nargin > 4)
+ print_usage();
+ endif
+
+ if (!isvector(padsize) || !isnumeric(padsize) || any(padsize < 0) || any(padsize != round(padsize)))
+ error("padarray: padsize must be a vector of positive integers.");
+ endif
+ if (!isscalar(padval) && !ischar(padval))
+ error("padarray: third input argument must be a string or a scalar");
+ endif
+ if (!ischar(direction) || strcmpi(direction, {"pre", "post", "both"}))
+ error("padarray: fourth input argument must be 'pre', 'post', or 'both'");
+ endif
+
+ ## Assure padsize is a row vector
+ padsize = padsize(:).';
+
+ # Check direction
+ pre = any(strcmpi(direction, {"pre", "both"}));
+ post = any(strcmpi(direction, {"post", "both"}));
+
+ B = A;
+ dim = 1;
+ for s = padsize
+ if (s > 0)
+ # padding in this dimension was requested
+ ds = size(B);
+ ds = [ds, ones(1,dim-length(ds))]; # data size
+ ps = ds;
+ ps(dim) = s; # padding size
+
+ if (ischar(padval))
+ # Init a "index all" cell array. All cases need it.
+ idx = cell(1, length(ds));
+ for i = 1:length(ds)
+ idx{i} = 1:ds(i);
+ endfor
+
+ switch (padval)
+ case ("circular")
+ complete = 0;
+ D = B;
+ if (ps(dim) > ds(dim))
+ complete = floor(ps(dim)/ds(dim));
+ ps(dim) = rem(ps(dim), ds(dim));
+ endif
+ if (pre)
+ for i = 1:complete
+ B = cat(dim, D, B);
+ endfor
+ idxt = idx;
+ idxt{dim} = ds(dim)-ps(dim)+1:ds(dim);
+ B = cat(dim, D(idxt{:}), B);
+ endif
+ if (post)
+ for i = 1:complete
+ B = cat(dim, B, D);
+ endfor
+ idxt = idx;
+ idxt{dim} = 1:ps(dim);
+ B = cat(dim, B, D(idxt{:}));
+ endif
+ # end circular case
+
+ case ("replicate")
+ if (pre)
+ idxt = idx;
+ idxt{dim} = 1;
+ pad = B(idxt{:});
+ # can we do this without the loop?
+ for i = 1:s
+ B = cat(dim, pad, B);
+ endfor
+ endif
+ if (post)
+ idxt = idx;
+ idxt{dim} = size(B, dim);
+ pad = B(idxt{:});
+ for i = 1:s
+ B = cat(dim, B, pad);
+ endfor
+ endif
+ # end replicate case
+
+ case ("symmetric")
+ if (ps(dim) > ds(dim))
+ error("padarray: padding is longer than data using symmetric padding");
+ endif
+ if (pre)
+ idxt = idx;
+ idxt{dim} = ps(dim):-1:1;
+ B = cat(dim, B(idxt{:}), B);
+ endif
+ if (post)
+ idxt = idx;
+ sbd = size(B, dim);
+ idxt{dim} = sbd:-1:sbd-ps(dim)+1;
+ B = cat(dim, B, B(idxt{:}));
+ endif
+ # end symmetric case
+
+ case ("reflect")
+ if (ps(dim) > ds(dim)-1)
+ error("padarray: padding is longer than data using 'reflect' padding");
+ endif
+ if (pre)
+ idxt = idx;
+ idxt{dim} = (ps(dim):-1:1) + 1;
+ B = cat(dim, B(idxt{:}), B);
+ endif
+ if (post)
+ idxt = idx;
+ sbd = size(B, dim)-1;
+ idxt{dim} = sbd:-1:sbd-ps(dim)+1;
+ B = cat(dim,B,B(idxt{:}));
+ endif
+ # end reflect case
+
+ otherwise
+ error("padarray: invalid string in padval parameter.");
+
+ endswitch
+ # end cases where padval is a string
+
+ elseif (isscalar(padval))
+ # Handle fixed value padding
+ if (padval == 0)
+ pad = zeros(ps, class(A)); ## class(pad) = class(A)
+ else
+ pad = padval*ones(ps, class(A)); ## class(pad) = class(A)
+ endif
+ if (pre && post)
+ # check if this is not quicker than just 2 calls (one for each)
+ B = cat(dim, pad, B, pad);
+ elseif (pre)
+ B = cat(dim, pad, B);
+ elseif (post)
+ B = cat(dim, B, pad);
+ endif
+ endif
+ endif
+ dim+=1;
+ endfor
+endfunction
+
+%!demo
+%! padarray([1,2,3;4,5,6],[2,1])
+%! % pads [1,2,3;4,5,6] with a whole border of 2 rows and 1 columns of 0
+
+%!demo
+%! padarray([1,2,3;4,5,6],[2,1],5)
+%! % pads [1,2,3;4,5,6] with a whole border of 2 rows and 1 columns of 5
+
+%!demo
+%! padarray([1,2,3;4,5,6],[2,1],0,'pre')
+%! % pads [1,2,3;4,5,6] with a left and top border of 2 rows and 1 columns of 0
+
+%!demo
+%! padarray([1,2,3;4,5,6],[2,1],'circular')
+%! % pads [1,2,3;4,5,6] with a whole 'circular' border of 2 rows and 1 columns
+%! % border 'repeats' data as if we tiled blocks of data
+
+%!demo
+%! padarray([1,2,3;4,5,6],[2,1],'replicate')
+%! % pads [1,2,3;4,5,6] with a whole border of 2 rows and 1 columns which
+%! % 'replicates' edge data
+
+%!demo
+%! padarray([1,2,3;4,5,6],[2,1],'symmetric')
+%! % pads [1,2,3;4,5,6] with a whole border of 2 rows and 1 columns which
+%! % is symmetric to the data on the edge
+
+% Test default padval and direction
+%!assert(padarray([1;2],[1]), [0;1;2;0]);
+%!assert(padarray([3,4],[0,2]), [0,0,3,4,0,0]);
+%!assert(padarray([1,2,3;4,5,6],[1,2]), \
+%! [zeros(1,7);0,0,1,2,3,0,0;0,0,4,5,6,0,0;zeros(1,7)]);
+
+% Test padding on 3D array
+%!test
+%! int8(0); % fail for octave <= 2.1.57 without crashing
+%! assert(padarray([1,2,3;4,5,6],[3,2,1]), cat(3, \
+%! zeros(8,7), \
+%! [zeros(3,7); [zeros(2,2), [1,2,3;4,5,6], zeros(2,2)]; zeros(3,7)], \
+%! zeros(8,7)));
+
+% Test if default param are ok
+%!assert(padarray([1,2],[4,5])==padarray([1,2],[4,5],0));
+%!assert(padarray([1,2],[4,5])==padarray([1,2],[4,5],0,'both'));
+
+% Test literal padval
+%!assert(padarray([1;2],[1],i), [i;1;2;i]);
+
+% Test directions (horizontal)
+%!assert(padarray([1;2],[1],i,'pre'), [i;1;2]);
+%!assert(padarray([1;2],[1],i,'post'), [1;2;i]);
+%!assert(padarray([1;2],[1],i,'both'), [i;1;2;i]);
+
+% Test directions (vertical)
+%!assert(padarray([1,2],[0,1],i,'pre'), [i,1,2]);
+%!assert(padarray([1,2],[0,1],i,'post'), [1,2,i]);
+%!assert(padarray([1,2],[0,1],i,'both'), [i,1,2,i]);
+
+% Test vertical padsize
+%!assert(padarray([1,2],[0;1],i,'both'), [i,1,2,i]);
+
+% Test circular padding
+%!test
+%! A=[1,2,3;4,5,6];
+%! B=repmat(A,7,9);
+%! assert(padarray(A,[1,2],'circular','pre'), B(2:4,2:6));
+%! assert(padarray(A,[1,2],'circular','post'), B(3:5,4:8));
+%! assert(padarray(A,[1,2],'circular','both'), B(2:5,2:8));
+%! % This tests when padding is bigger than data
+%! assert(padarray(A,[5,10],'circular','both'), B(2:13,3:25));
+
+% Test replicate padding
+%!test
+%! A=[1,2;3,4];
+%! B=kron(A,ones(10,5));
+%! assert(padarray(A,[9,4],'replicate','pre'), B(1:11,1:6));
+%! assert(padarray(A,[9,4],'replicate','post'), B(10:20,5:10));
+%! assert(padarray(A,[9,4],'replicate','both'), B);
+
+% Test symmetric padding
+%!test
+%! A=[1:3;4:6];
+%! HA=[3:-1:1;6:-1:4];
+%! VA=[4:6;1:3];
+%! VHA=[6:-1:4;3:-1:1];
+%! B=[VHA,VA,VHA; HA,A,HA; VHA,VA,VHA];
+%! assert(padarray(A,[1,2],'symmetric','pre'), B(2:4,2:6));
+%! assert(padarray(A,[1,2],'symmetric','post'), B(3:5,4:8));
+%! assert(padarray(A,[1,2],'symmetric','both'), B(2:5,2:8));
+
+% Repeat some tests with int* uint* class types
+%!assert(padarray(int8([1;2]),[1]), int8([0;1;2;0]));
+%!assert(padarray(uint8([3,4]),[0,2]), uint8([0,0,3,4,0,0]));
+%!assert(padarray(int16([1;2]),[1],4), int16([4;1;2;4]));
+%!assert(padarray(uint16([1;2]),[1],0), uint16([0;1;2;0]));
+%!assert(padarray(int32([1;2]),[1],int32(4),'pre'), int32([4;1;2]));
+%!assert(padarray(uint32([1;2]),[1],6,'post'), uint32([1;2;6]));
+
+% Test circular padding with int* uint* class types
+%!test
+%! A=int8([1,2,3;4,5,6]);
+%! B=repmat(A,7,9);
+%! assert(padarray(A,[1,2],'circular','pre'), B(2:4,2:6));
+%! assert(padarray(A,[1,2],'circular','post'), B(3:5,4:8));
+%! assert(padarray(A,[1,2],'circular','both'), B(2:5,2:8));
+%! % This tests when padding is bigger than data
+%! assert(padarray(A,[5,10],'circular','both'), B(2:13,3:25));
+
+% Test replicate padding with int* uint* class types
+%!test
+%! A=uint8([1,2;3,4]);
+%! B=[ones(10,5,"uint8")*1,ones(10,5,"uint8")*2; \
+%! ones(10,5,"uint8")*3,ones(10,5,"uint8")*4];
+%! assert(padarray(A,[9,4],'replicate','pre'), B(1:11,1:6));
+%! assert(padarray(A,[9,4],'replicate','post'), B(10:20,5:10));
+%! assert(padarray(A,[9,4],'replicate','both'), B);
+
+% Test symmetric padding with int* uint* class types
+%!test
+%! A=int16([1:3;4:6]);
+%! HA=int16([3:-1:1;6:-1:4]);
+%! VA=int16([4:6;1:3]);
+%! VHA=int16([6:-1:4;3:-1:1]);
+%! B=[VHA,VA,VHA; HA,A,HA; VHA,VA,VHA];
+%! assert(padarray(A,[1,2],'symmetric','pre'), B(2:4,2:6));
+%! assert(padarray(A,[1,2],'symmetric','post'), B(3:5,4:8));
+%! assert(padarray(A,[1,2],'symmetric','both'), B(2:5,2:8));
+
+
+
+%
+% $Log$
+% Revision 1.2 2007/03/23 16:14:37 adb014
+% Update the FSF address
+%
+% Revision 1.1 2006/08/20 12:59:35 hauberg
+% Changed the structure to match the package system
+%
+% Revision 1.6 2005/09/08 02:00:17 pkienzle
+% [for Bill Denney] isstr -> ischar
+%
+% Revision 1.5 2004/09/03 18:33:11 pkienzle
+% skip tests which use cat(3,X,Y) for octave <= 2.1.57
+%
+% Revision 1.4 2004/09/03 13:37:10 jmones
+% Corrected behaviour for int* and uint* types
+%
+% Revision 1.3 2004/08/15 19:21:50 jmones
+% support column vector padsize
+%
+% Revision 1.2 2004/08/11 15:04:59 pkienzle
+% Convert dos line endings to unix line endings
+%
+% Revision 1.1 2004/08/08 21:20:25 jmones
+% uintlut and padarray functions added
+%
+%
git://git.creatis.insa-lyon.fr / CreaPhase.git / blobdiff