[981280]: blockproc / blockana.m Maximize Restore History

Download this file

blockana.m    209 lines (190 with data), 7.0 kB

  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
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
function [c, fola] = blockana(F, f, fola)
%BLOCKANA Blockwise analysis interface
% Usage: c=blockana(F, f)
%
% Input parameters:
% Fa : Analysis frame object.
% f : Block of signal.
% fola : Explicitly defined overlap
% Output parameters:
% c : Block coefficients.
% fola : Stored overlap
%
% `c=blockana(Fa,f)` calculates the coefficients *c* of the signal block *f* using
% the frame defined by *F*. The block overlaps are handled according to the
% `F.blokalg`. Assuming |blockana| is called in the loop only once, *fola*
% can be omitted and the overlaps are handled in the background
% automatically.
%
% See also: block, blocksyn, blockplay
%
% References: dogrhove12 ltfatnote026
if nargin<2
error('%s: Too few input parameters.',upper(mfilename));
end;
if ~isstruct(F)
error('%s: First agument must be a frame definition structure.',upper(mfilename));
end;
if nargin<3
fola = [];
end
if ~isfield(F,'blockalg')
F.blockalg = 'naive';
end
% Block length
Lb = size(f,1);
% Next block index start (from a global point of view, starting with zero)
nextSb = block_interface('getPos');
% Block index start (from a global point of view, starting with zero)
Sb = nextSb-Lb;
do_sliced = strcmp(F.blockalg,'sliced');
do_segola = strcmp(F.blockalg,'segola');
if strcmp(F.blockalg,'naive')
% Most general. Should work for anything.
% Produces awful block artifacts when coefficients are altered.
f = [f; zeros(F.L-size(f,1),size(f,2))];
c = F.frana(f);
elseif do_sliced || do_segola
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% STEP 1) Determine overlap lengths
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if do_sliced
% Sliced real-time block processing
% Equal block length assumtion
Sbolen = Lb;
nextSbolen = Lb;
else
if ~isfield(F,'winLen')
error('%s: Frame does not have FIR windows.',upper(mfilename));
end
% Window length
Lw = F.winLen;
switch(F.type)
case 'fwt'
J = F.J;
w = F.g;
m = numel(w.h{1}.h);
a = w.a(1);
if Lb<a^J
error('%s: Minimum block length is %i.',upper(mfilename),a^J);
end
rred = (a^J-1)/(a-1)*(m-a);
Sbolen = rred + mod(Sb,a^J);
nextSbolen = rred + mod(nextSb,a^J);
case {'dgtreal','dgt','dwilt','wmdct'}
a = F.a;
Sbolen = ceil((Lw-1)/a)*a + mod(Sb,a);
nextSbolen = ceil((Lw-1)/a)*a + mod(nextSb,a);
case {'filterbank','filterbankreal','ufilterbank','ufilterbankreal'}
a = F.lcma;
if Lw-1 < a
Sbolen = mod(Sb,a);
nextSbolen = mod(nextSb,a);
else
Sbolen = ceil((Lw-1)/a)*a + mod(Sb,a);
nextSbolen = ceil((Lw-1)/a)*a + mod(nextSb,a);
end
%Sbolen = ceil((Lw-1)/a)*a + mod(Sb,a);
%nextSbolen = ceil((Lw-1)/a)*a + mod(nextSb,a);
otherwise
error('%s: Unsupported frame.',upper(mfilename));
end
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% STEP 2) Common overlap handling
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Append the previous block
fext = [loadOverlap(Sbolen,size(f,2),fola);f];
% Save the current block
if nargout>1
fola = storeOverlap(fext,nextSbolen);
else
storeOverlap(fext,nextSbolen);
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% STEP 3) Do the rest
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if do_sliced
% Multiply by the slicing window (all channels)
fwin = bsxfun(@times,F.sliwin,fext);
% If some padding is necessary, do it symmetrically
pad = F.L-size(fwin,1);
W = size(fwin,2);
fwin = [zeros(floor(pad/2),W);...
fwin;...
zeros(ceil(pad/2),W)];
% Apply transform
c = F.frana(fwin);
else
switch(F.type)
case 'fwt'
c = block_fwt(fext,w,J);
case {'dgtreal','dgt','dwilt','wmdct'}
Lwl = floor(Lw/2);
Lext = Sbolen + Lb - nextSbolen + Lwl;
startc = ceil(Lwl/a)+1;
endc = ceil((Lext)/a);
% Pad with zeros to comply with the frame requirements
fext = [fext; zeros(F.L-size(fext,1),size(fext,2))];
c = F.frana(fext(1:F.L,:));
% Pick just valid coefficients
cc = F.coef2native(c,size(c));
cc = cc(:,startc:endc,:);
c = F.native2coef(cc);
case {'filterbank','filterbankreal'}
% Subsampling factors
a = F.a(:,1);
% Filter lengths
gl = F.g_info.gl;
% Filter offsets
Lwl = max(gl+F.g_info.offset-1);
Lext = Sbolen + Lb - nextSbolen + Lwl;
startc = ceil(Lwl./a)+1;
endc = ceil((Lext)./a);
fext = [fext; zeros(F.L-size(fext,1),size(fext,2))];
c = F.frana(fext(1:F.L,:));
cc = F.coef2native(c,size(c));
cc = cellfun(@(cEl,sEl,eEl) cEl(sEl:eEl,:),cc,num2cell(startc),num2cell(endc),'UniformOutput',0);
c = F.native2coef(cc);
end
end
else
error('%s: Frame was not created with blockaccel.',upper(mfilename));
end
end % BLOCKANA
function overlap = loadOverlap(L,chan,overlap)
%LOADOVERLAP Loads overlap
%
%
if isempty(overlap)
overlap = block_interface('getAnaOverlap');
end
% Supply zeros if it is empty
if isempty(overlap)
overlap = zeros(L,chan,block_interface('getClassId'));
end
Lo = size(overlap,1);
if nargin<1
L = Lo;
end
% If required more than stored, do zero padding
if L>Lo
oTmp = zeros(L,size(overlap,2));
oTmp(end-Lo+1:end) = oTmp(end-Lo+1:end)+overlap;
overlap = oTmp;
else
overlap = overlap(end-L+1:end,:);
end
end % LOADOVERLAP
function overlap = storeOverlap(fext,L)
%STOREOVERLAP Stores overlap
%
%
if L>size(fext,1)
error('%s: Storing more samples than passed.',upper(mfilename));
end
overlap = fext(end-L+1:end,:);
if nargout<1
block_interface('setAnaOverlap',overlap);
end
end % STOREOVERLAP