%ALPHA 0.6 FOR RGB PWM REACTIVE LIGHTING : AS IF ACTUALLY SAMPLING
%Joe Swelland 5/11/2018
%==========================================================================
%ALPHA 0.5 : Introduction of Peak Detection
%Import Audio
[clip, Fs] = audioread('hose5.wav'); %Import test song
clipt = clip(:,1);

%=======================================================================
%FILTERING
%-----------------------------------------------------------------------
%controls
lowfc = 150;
midfc = 600;
highfc = midfc;
intensity = 1; %background intensity

%COLOR ASSIGNMENTS (RANDOMLY CHOSEN)
%LOW SPECTRUM - BLUE
[lowA, lowB] = butter(4,lowfc/(Fs/2));
%MID SPECTRUM - GREEN
[midA, midB] = butter(4,[lowfc/(Fs/2) midfc/(Fs/2)]);
%HIGH SPECTRUM - RED
[highA, highB] = butter(4,highfc/(Fs/2), 'high');

%SIGNAL FILTERING
%LOW
lowFl = intensity * filter(lowA,lowB,clipt);
%MID
midFl = intensity * filter(midA,midB,clipt);
%HIGH
highFl = intensity * filter(highA,highB,clipt);

%======================================================================
%UPDATE FRAMES : to hold value of color for X duration
%----------------------------------------------------------------------
%controls
cnt = 0; %iterator
interval = 0.05; %time in seconds for color duration
win = interval * Fs;

%LOW
blueFrame = zeros(length(clipt),1);
maxVolume = 0;
for i=1:length(clipt)
    volume = abs(lowFl(i));
    if (cnt > win)
        maxVolume = volume;
        cnt = 0;
    else
        cnt = cnt + 1; %increment window counter
        if (volume > maxVolume)
            maxVolume = volume;
            cnt = 0; %reset window counter
        end
    end
    blueFrame(i) = maxVolume;
end
%MID
greenFrame = zeros(length(clipt),1);
maxVolume = 0;
for i=1:length(clipt)
    volume = abs(midFl(i));
    if (cnt > win)
        maxVolume = volume;
        cnt = 0;
    else
        cnt = cnt + 1; %increment window counter
        if (volume > maxVolume)
            maxVolume = volume;
            cnt = 0; %reset window counter
        end
    end
    greenFrame(i) = maxVolume;
end
%HIGH
redFrame = zeros(length(clipt),1);
maxVolume = 0;
for i=1:length(clipt)
    volume = abs(highFl(i));
    if (cnt > win)
        maxVolume = volume;
        cnt = 0;
    else
        cnt = cnt + 1; %increment window counter
        if (volume > maxVolume)
            maxVolume = volume;
            cnt = 0; %reset window counter
        end
    end
    redFrame(i) = maxVolume;
end

%==========================================================================
%BUMP DETECTOR
%--------------------------------------------------------------------------
%controls
volume = 0;
avgTot = 0;
avgLog = zeros((floor(0.07*Fs)),1);
currAvg = zeros(length(clipt),1);
logSlope = zeros(length(clipt),1);
a = 1; %iterator
lastAvg = 0;
up = 1;
peak = 0;
n = 0; %iterator
%lowAvgLog=zeros(length(clipt),1);


for i=1:length(clipt)
    volume = abs(clipt(i)); %grab current sample
    if (a > (floor(0.07 * Fs))) %average array rollover
        a = 1;
        avgTot = avgTot - avgLog(a);
        avgLog(a) = volume;
        avgTot = avgTot + avgLog(a);
    else %non-rollover
        avgTot = avgTot - avgLog(a);
        avgLog(a) = volume;
        avgTot = avgTot + avgLog(a);
        a = a + 1;
    end
   %Update average
   currAvg(i) = avgTot/(0.07*Fs);
   %Slope Detection of Average
   if (up) %Upwards mode
       if (currAvg(i) > lastAvg)
           lastAvg = currAvg(i);
           n = 0;
       elseif (currAvg(i) < lastAvg)
           if (n >(0.5*Fs)) %will only switch to down if no new max in entire window length n
             %peak detected, follow down next
             if (abs(currAvg(i) - lastAvg) > lastAvg/4) %if the change is tiny, probably not a big enough slope change
               up = 0;
               peak = 0; %sound peak detected toggle
             end
             n = 0; %reset window counter
           else
              n = n + 1; %increment window counter
           end
       end
   elseif (up==0) %Downwards mode, works mostly same as upwards.
       if (currAvg(i) < lastAvg)
           lastAvg = currAvg(i);
           n = 0;
       elseif (currAvg(i) > lastAvg)
           if (n > (0.5*Fs))
               %trough detected, follow up next
               if (abs(currAvg(i) - lastAvg) > currAvg(i)/4)
                    up = 1;
                    peak = 1;
               end
               n = 0;
           else
               n = n + 1;
           end
       end
   end
   %if currently in a sound bump
   if (peak)
       logSlope(i) = 1 - fade; %decay intensity of bump
       fade = fade + logSlope(i)/10000; %decay rate, made it up.
   else
       logSlope(i) = 0; %if not bumping, bump effect = 0
       fade = 0;
   end
end

%==========================================================================
%ADD BUMP TO FRAMES : still under develeopment. not sure how I want to have
%a bump effect color.
%--------------------------------------------------------------------------
for i=1:length(clipt)
    if (blueFrame(i) > redFrame(i) && blueFrame(i) > greenFrame(i) && logSlope(i))
        greenFrame(i) = redFrame(i) + logSlope(i);
        %redFrame(i) = greenFrame(i) + logSlope(i);
        %blueFrame(i) = blueFrame(i);
    elseif (redFrame(i) > blueFrame(i) && redFrame(i) > greenFrame(i) && logSlope(i))
        %greenFrame(i) = greenFrame(i) + logSlope(i);
        blueFrame(i) = blueFrame(i) + logSlope(i);
        %redFrame(i) = redFrame(i);
    elseif (greenFrame(i) > blueFrame(i) && greenFrame(i) > redFrame(i) && logSlope(i))
        redFrame(i) = redFrame(i) + logSlope(i);
        %blueFrame(i) = blueFrame(i) + logSlope(i);
        %greenFrame(i) = greenFrame(i);
    end
end

%==========================================================================
%SIMULATION OF LIGHTS : draws a "square" frame of color representing the
%RGB output to the LED
%--------------------------------------------------------------------------
%controls
spacing = 5;%width in pixels of each color frame
draw_start = 0; %seconds
draw_time = 120; %seconds
current = 1; %image array index for colors
total_samples = draw_time * Fs; %total samples expected to be drawn.
squares = total_samples/(interval*Fs); %amount of squares of color to draw. Squares SHOULD be length = interval seconds
next = current + spacing; %jump pixels to next color
move = 0; %reseting just incase
drw_smple_start = draw_start*Fs; %image sample start
stream=zeros(500, floor(squares), 3); %create image stream

for i=1:floor(squares)
    move = move + (interval*Fs);

    %SQUARE CREATION
    stream(:,current:next,1)= redFrame(drw_smple_start+move); %RED
    stream(:,current:next,2)= greenFrame(drw_smple_start+move); %GREEN
    stream(:,current:next,3)= blueFrame(drw_smple_start+move); %BLUE
    %Move to next box
    current = current + spacing;
    next = next + spacing;
end

figure(1)
imshow(stream)