samer@0: % abufsig - Arrow which produces multiple buffered frames from a signal
samer@0: %
samer@0: % abufsig :: 
samer@0: %    signal(C,R),
samer@0: %    N:natural ~'block size',
samer@0: %    M:natural ~'hop size',
samer@0: %    L:natural ~'buffer width'
samer@0: % -> arrow({},{[[N*C,L]]}).
samer@0: %
samer@0: % abufsig :: 
samer@0: %    signal(C,R),
samer@0: %    N:natural ~'block size',
samer@0: %    M:natural ~'hop size'
samer@0: % -> arrow({},{[[N*C,1]]]}).
samer@0: %
samer@0: % abufsig :: 
samer@0: %    signal(C,R),
samer@0: %    N:natural ~'block size',
samer@0: % -> arrow({},{[[C*N,1]]]}).
samer@0: %
samer@0: % If hop size is omitted, it defaults to the block size.
samer@0: % If buffer width is omitted, it defaults to 1.
samer@0: 
samer@0: function o=abufsig(source,block,hop,width)
samer@0: 	if nargin<4, width=1; end
samer@0: 	if nargin<3, hop=block; end
samer@0: 
samer@0: 	ch=channels(source);
samer@0: 	if (mod(block,ch)>0 || mod(hop,ch))
samer@0: 		error('Block size and hop must be a multiple of channel count'); 
samer@0: 	end
samer@0: 
samer@0: 	if width==1,
samer@0: 		o=asignal(source,block/ch,hop/ch)*arr(@flt);
samer@0: 	else
samer@0: 		olap = block-hop;
samer@0: 		span = (hop*(width-1)+block);	
samer@0: 		jump = (hop*width);
samer@0: 		o=asignal(source,span/ch,jump/ch)*arr(@buf);
samer@0: 	end
samer@0: 
samer@0: 	function y=flt(x), y=x(:); end
samer@0: 	function y=buf(x), y=buffer(x(:),block,olap,'nodelay'); end
samer@0: end
samer@0: