% Setiv1.m
%
%


% Initialization
	clear all; pack;
	clc; pause(0.5);

% Setable Parameters
	viewgraphs = 0;	% if 1 then show plot, fft, specgram
							% warning, takes forever
	fileext = '.wav';
	workingRAM = 400;  % in Mb, RAM available after loading matlab
	workingdir = 'E:\MATLABR11\work\';



% 	READING, NORMALIZING AND WRITING OUT THE DATA

% User picks wav file from directory's list   
%	cd(workingdir)
%  for testing pick a specific file
filename = 'min15';	% 96 sec at work, 150 sec at home
%filename = 'hour';	% 368 sec at work
ext = '.wav';
filen = strcat(workingdir, filename, ext);

%d = dir('*.au')
%str = {d.name};
%[s,v] = listdlg('PromptString','Select data file:',...
%                'SelectionMode','single',...
%                'ListString',str)
%npts = auread(char(str(s)), 'size')	% # of points in au file

% load wavefile into workspace
	disp('Reading in wav file');
	[y,fs,format] = wavread16(filen);
	T = 1/fs;	% T is the period
	npts = size(y);

% Normalize the data
	% set range to -1 to 1 and remove mean
%	if format(6) = 8 	% 8 bits, -128 to +128
		y = (y - mean(y))/128;		% assume for now 8 bit mono
%	end
	
% write file out since it is too big to keep in memory
	disp('Writing out normalized raw file');
	rawfile = strcat(workingdir, filename, '.raw');
	fid = fopen(rawfile, 'w');	
	if fid==-1
		error('Failure to open raw file for writing');
	end
	count = fwrite(fid, y, 'double');
	fclose(fid);
	if count ~= npts(1)
		error('Failure to write out complete raw file');
	end
	
% clear large data matrix and repack memory
	clear y
	pack


% PROCESSING 2^n SIZED BLOCKS OF DATA 

% Givens
%	1. Window size runs from 2^14 for 2 sec 
%		to 2^19 for 64 secs

% How much to read at a time to process
%			  n			2^n			# of 2^n windows possible
%											with padding on last window
% ------------------------------------------------------
%a = [[14:19; 	2.^(14:19)]' ceil((npts(1)./2.^(14:19))')]
%a =       14       16384        1758
%          15       32768         879
%          16       65536         440
%          17      131072         220
%          18      262144         110
%          19      524288          55


fid = fopen(rawfile, 'r');	
if fid==-1
	error('Failure to open raw file for reading');
end

disp('Begining Processing');
tic
for powerof2 = 14:19	% should be 14:19
	disp(['Window Size = 2^', num2str(powerof2)]);
	% total # vectors possible with 2^powerof2 for file size
	totalnumwindows = ceil((npts(1)/2^(powerof2)));
	if totalnumwindows < 2
		break
	end
	disp([num2str(totalnumwindows),...
			' total number of windows this size']);
	% nww = # of vectors of size 2^powerof2 to read in at a time.
	nww = floor((workingRAM-50)*1000000/(8*10*2^powerof2));
	disp(['Processing ', num2str(nww), ' windows as a matrix']);
	% set file position pointer at begining of file
	pause(0.5); % for disp to appear
	frewind(fid);
	for k =1:nww:totalnumwindows
% BEGINING MAIN PROCESSING AREA FOR VECTORIZED OPERATIONS 
		Y = fread(fid, [2^powerof2 nww], 'double');
		%pause(0.2);	% for control-C halting for program
		fftY = abs(fft(Y, 2^powerof2));
% END OF MAIN PROCESSING AREA FOR VECTORIZED OPERATIONS
		size(fftY)
		if viewgraphs 	% takes forever
			for kk = 1:nww
				subplot(3,1,1);	plot(Y(:,kk))
				subplot(3,1,2);	bar(fftY(1:(2^powerof2/2+1),kk))
				subplot(3,1,3);	specgram(Y(:,kk))
				drawnow; pause(1);	% graphs won't update without delay
			end % kk for loop
		end % visual if
	end % k for loop
end % powerof2 loop
t = toc; disp(['elapsed time: ',num2str(round(t)), ' sec'])

fclose(fid);
	
disp('Finished Setiv1.m')