Fixes for TNS, Level 2 finalization

Level_2/AACoder2.m

@@ -27,10 +27,6 @@ function AACSeq2 = AACoder2(fNameIn)
         nextFrameStart = (i + 1) * 1024 + 1;
         nextFrameStop = nextFrameStart + 2047;
         frameTypes{i+1} = SSC(1, originalAudioData(nextFrameStart:nextFrameStop, :), frameTypes{i});
-
-%         if strcmp(frameTypes{i+1}, 'ESH')
-%             i
-%         end
     end
 
     % Assigns a type to the last frame

Level_2/TNS.m

@@ -22,8 +22,9 @@ function [frameFout, TNScoeffs] = TNS(frameFin, frameType)
     SHORT_WINDOW_NUMBER_OF_BANDS = 42;
     % Declares constant order of the linear prediction filter
     LPF_ORDER = 4;
-    % Declares constant coefficients' resolution
+    % Declares constant coefficients' resolution, in the form of number of
-    COEF_RES = 4;
+    % decimal digits used
+    COEF_RES = 1;
 
     % Declares persistent variable holding the TNS tables and initializes if empty
     persistent TNSTables;
@@ -37,26 +38,13 @@ function [frameFout, TNScoeffs] = TNS(frameFin, frameType)
         for band = 1:LONG_WINDOW_NUMBER_OF_BANDS - 1
             bandEnergy(band) = sumsqr(frameFin(TNSTables.B219a(band, 2) + 1:TNSTables.B219a(band + 1, 2)));
         end
-        bandEnergy(LONG_WINDOW_NUMBER_OF_BANDS) = sumsqr( ...
+        bandEnergy(LONG_WINDOW_NUMBER_OF_BANDS) = sumsqr(frameFin( ...
-            frameFin(TNSTables.B219a(LONG_WINDOW_NUMBER_OF_BANDS, 2) + 1:...
+            TNSTables.B219a(LONG_WINDOW_NUMBER_OF_BANDS, 2) + 1:end));
-            TNSTables.B219a(LONG_WINDOW_NUMBER_OF_BANDS, 3) + 1));
 
         % Calculates the normalization factors
-        
-        % PROBABLY WRONG, THE ONE BELLOW SHOULD BE RIGHT AND BETTER
-%         normalizationFactor(1024) = 0;
-%         for normIndex = 1:1024
-%             bandIndices = find(TNSTables.B219a(:, 2) >= (normIndex - 1), 1);
-%             if ~isempty(bandIndices)
-%                 normalizationFactor(normIndex) = sqrt(bandEnergy(bandIndices));
-%             else
-%                 normalizationFactor(normIndex) = sqrt(bandEnergy(find(TNSTables.B219a(:, 3) >= normIndex - 1, 1)));
-%             end
-%         end
-
         bandIndices = quantiz(0:1023, TNSTables.B219a(:, 2) - 1);
         normalizationFactor = sqrt(bandEnergy(bandIndices));
-        
+
         % Smooths normalization factors
         for normIndex = 1023:-1:1
             normalizationFactor(normIndex) = (normalizationFactor(normIndex) + normalizationFactor(normIndex + 1)) / 2;
@@ -72,58 +60,34 @@ function [frameFout, TNScoeffs] = TNS(frameFin, frameType)
         [linPredCoeff, ~] = lpc(normalizedFrameFin, LPF_ORDER);
 
         % Quantizes these coefficients
-        quantizedLinPredCoeff(LPF_ORDER) = 0;
+        quantizedLinPredCoeff = round(linPredCoeff, COEF_RES);
-        for coeffIndex = 2:length(linPredCoeff)
+
-            quantizedLinPredCoeff(coeffIndex - 1) = asin(linPredCoeff(coeffIndex));
-            if linPredCoeff(coeffIndex) >= 0
-                quantizedLinPredCoeff(coeffIndex - 1) = round(quantizedLinPredCoeff(coeffIndex - 1) * ...
-                    (bitshift(1, COEF_RES - 1) - 0.5) / (pi / 2));
-                quantizedLinPredCoeff(coeffIndex - 1) = quantizedLinPredCoeff(coeffIndex - 1) / ...
-                    (bitshift(1, COEF_RES - 1) - 0.5) / (pi / 2);
-                quantizedLinPredCoeff(coeffIndex - 1) = sin (quantizedLinPredCoeff(coeffIndex - 1));
-            else
-                quantizedLinPredCoeff(coeffIndex - 1) = round(quantizedLinPredCoeff(coeffIndex - 1) * ...
-                    (bitshift(1, COEF_RES - 1) + 0.5) / (pi / 2));
-                quantizedLinPredCoeff(coeffIndex - 1) = quantizedLinPredCoeff(coeffIndex - 1) / ...
-                    (bitshift(1, COEF_RES - 1) + 0.5) / (pi / 2);
-                quantizedLinPredCoeff(coeffIndex - 1) = sin (quantizedLinPredCoeff(coeffIndex - 1));
-            end
-        end
-        
         % Filters MDCT coefficients
-        if ~isstable(1, [1 (quantizedLinPredCoeff * (-1))])
+        if ~isstable(1, quantizedLinPredCoeff)
             error('TNS, l[79]: Inverse filter not stable!');
         else
-            TNScoeffs = quantizedLinPredCoeff;
+            TNScoeffs = quantizedLinPredCoeff(2:end);
-            frameFout = filter([1 (quantizedLinPredCoeff * (-1))], 1, frameFin);
+            frameFout = filter(quantizedLinPredCoeff, 1, frameFin);
         end
     else
         % Initializes output vectors
         TNScoeffs(LPF_ORDER * 8) = 0;
         frameFout(1024) = 0;
-        
+
         bandEnergy(SHORT_WINDOW_NUMBER_OF_BANDS) = 0;
         for subFrameIndex = 1:8
             subFrame = frameFin((subFrameIndex - 1) * 128 + 1:subFrameIndex * 128);
-            
+
             % Calculates the energy per band
             for band = 1:SHORT_WINDOW_NUMBER_OF_BANDS - 1
                 bandEnergy(band) = sumsqr(subFrame(TNSTables.B219b(band, 2) + 1:TNSTables.B219b(band + 1, 2)));
             end
-            bandEnergy(SHORT_WINDOW_NUMBER_OF_BANDS) = sumsqr( ...
+            bandEnergy(SHORT_WINDOW_NUMBER_OF_BANDS) = sumsqr(subFrame( ...
-                subFrame(TNSTables.B219b(SHORT_WINDOW_NUMBER_OF_BANDS, 2) + 1:...
+                TNSTables.B219b(SHORT_WINDOW_NUMBER_OF_BANDS, 2) + 1:end));
-                TNSTables.B219b(SHORT_WINDOW_NUMBER_OF_BANDS, 3) + 1));
 
             % Calculates the normalization factors
-            normalizationFactor(128) = 0;
+            bandIndices = quantiz(0:127, TNSTables.B219b(:, 2) - 1);
-            for normIndex = 1:128
+            normalizationFactor = sqrt(bandEnergy(bandIndices));
-                bandIndices = find(TNSTables.B219b(:, 2) >= normIndex - 1, 1);
-                if ~isempty(bandIndices)
-                    normalizationFactor(normIndex) = sqrt(bandEnergy(bandIndices));
-                else
-                    normalizationFactor(normIndex) = sqrt(bandEnergy(find(TNSTables.B219b(:, 3) <= normIndex - 1, 1)));
-                end
-            end
 
             % Smooths normalization factors
             for normIndex = 127:-1:1
@@ -140,33 +104,16 @@ function [frameFout, TNScoeffs] = TNS(frameFin, frameType)
             [linPredCoeff, ~] = lpc(normalizedFrameFin, LPF_ORDER);
 
             % Quantizes these coefficients
-            quantizedLinPredCoeff(LPF_ORDER) = 0;
+            quantizedLinPredCoeff = round(linPredCoeff, COEF_RES);
-            for coeffIndex = 1:length(linPredCoeff)
-                quantizedLinPredCoeff(coeffIndex - 1) = asin(linPredCoeff(coeffIndex));
-                if linPredCoeff(coeffIndex) >= 0
-                    quantizedLinPredCoeff(coeffIndex - 1) = round(quantizedLinPredCoeff(coeffIndex - 1) * ...
-                        (bitshift(1, COEF_RES - 1) - 0.5) / (pi / 2));
-                    quantizedLinPredCoeff(coeffIndex - 1) = quantizedLinPredCoeff(coeffIndex - 1) / ...
-                    (bitshift(1, COEF_RES - 1) - 0.5) / (pi / 2);
-                    quantizedLinPredCoeff(coeffIndex - 1) = sin (quantizedLinPredCoeff(coeffIndex - 1));
-                else
-                    quantizedLinPredCoeff(coeffIndex - 1) = round(quantizedLinPredCoeff(coeffIndex - 1) * ...
-                        (bitshift(1, COEF_RES - 1) + 0.5) / (pi / 2));
-                    quantizedLinPredCoeff(coeffIndex - 1) = quantizedLinPredCoeff(coeffIndex - 1) / ...
-                    (bitshift(1, COEF_RES - 1) + 0.5) / (pi / 2);
-                    quantizedLinPredCoeff(coeffIndex - 1) = sin (quantizedLinPredCoeff(coeffIndex - 1));
-                end
-            end
 
             % Filters MDCT coefficients
-            if ~isstable(1, [1 (quantizedLinPredCoeff * (-1))])
+            if ~isstable(1, quantizedLinPredCoeff)
                 error('TNS, l[79]: Inverse filter not stable!');
             else
-                TNScoeffs((subFrameIndex - 1) * 4 + 1:subFrameIndex * 4) = quantizedLinPredCoeff;
+                TNScoeffs((subFrameIndex - 1) * 4 + 1:subFrameIndex * 4) = quantizedLinPredCoeff(2:end);
                 frameFout((subFrameIndex - 1) * 128 + 1:subFrameIndex * 128) = ...
-                    filter([1 (quantizedLinPredCoeff * (-1))], 1, subFrame);
+                    filter(quantizedLinPredCoeff, 1, subFrame);
             end
         end
     end
 end
-

Level_2/iTNS.m

@@ -25,14 +25,14 @@ function frameFout = iTNS(frameFin, frameType, TNScoeffs)
 
     if ~strcmp(frameType, 'ESH')
         % Inverses MDCT coefficients filtering
-        frameFout = filter(1, [1 (-1 * TNScoeffs)], frameFin);
+        frameFout = filter(1, [1 TNScoeffs], frameFin);
     else
         for subFrameIndex = 1:8
             subFrame = frameFin((subFrameIndex - 1) * 128 + 1:subFrameIndex * 128);
 
             % Inverses MDCT coefficients filtering
             frameFout((subFrameIndex - 1) * 128 + 1:subFrameIndex * 128) = ...
-                filter(1, [1 (-1 * TNScoeffs)], subFrame);
+                filter(1, [1 TNScoeffs((subFrameIndex - 1) * 4 + 1:subFrameIndex * 4)], subFrame);
         end
     end
 end