deriving post filter freqs from decoded mask when dec-in-time, seems to work OK

git-svn-id: https://svn.code.sf.net/p/freetel/code@2750 01035d8c-6547-0410-b346-abe4f91aad63

diff --git a/codec2-dev/octave/newamp.m b/codec2-dev/octave/newamp.m
index 1f0b4e8fb025796e6238c59fab9bfbd5985883d6..b6cecba953bf2607860f0a080cbc347cf202a216 100644 (file)
--- a/codec2-dev/octave/newamp.m
+++ b/codec2-dev/octave/newamp.m
@@ -271,7 +271,7 @@ function [decmaskdB masker_freqs_kHz min_error mse_log1 mse_log2] = make_decmask
 
       % quantise the deltas
 
-      masker_amps_dB_lin_delta_ = zeros(4,1);
+      masker_amps_dB_lin_delta_ = zeros(Nsamples,1);
       if amp_quant == 1
         for i=1:Nsamples
           masker_amps_dB_lin_delta_(i) = quantise(-21:3:21, masker_amps_dB_lin_delta(i));

diff --git a/codec2-dev/octave/newamp_batch.m b/codec2-dev/octave/newamp_batch.m
index 6c0129ac01bdec96f30ed1ffbcec65b6c4afb7ec..f7c6118eeae72c2eba9cfd4e617ea51c6c30343d 100644 (file)
--- a/codec2-dev/octave/newamp_batch.m
+++ b/codec2-dev/octave/newamp_batch.m
@@ -21,7 +21,7 @@ function [non_masked_f_log non_masked_amp_log] = newamp_batch(samname, optional_
   more off;
 
   max_amp = 80;
-  decimate_in_freq = 1;
+  decimate_in_freq = 0;
   postfilter = 1;
   decimate_in_time = 1;
   synth_phase = 1;
@@ -74,7 +74,12 @@ function [non_masked_f_log non_masked_amp_log] = newamp_batch(samname, optional_
       [decmaskdB masker_freqs_kHz] = make_decmask_abys(maskdB, AmdB, Wo, L, mask_sample_freqs_kHz, freq_quant, amp_quant);
       non_masked_amp = decmaskdB;
       non_masked_amp_log = [non_masked_amp_log; non_masked_amp'];
+
+      % Save this for decoder, so it knows where to apply post filter
+      % Basically the frequencies of the AbyS samples
+
       non_masked_m(f,:) = min(round(masker_freqs_kHz/(Wo*4/pi)),L);
+
       non_masked_m_log = [non_masked_m_log; non_masked_m(f,:)'];
       non_masked_f_log = [non_masked_f_log; masker_freqs_kHz];
       maskdB_ = decmaskdB;
@@ -94,25 +99,52 @@ function [non_masked_f_log non_masked_amp_log] = newamp_batch(samname, optional_
   % decoder loop -----------------------------------------------------
 
   for f=1:frames
+    %printf("frame: %d\n", f);
     L = min([model_(f,2) max_amp-1]);
     Wo = model_(f,1);
     Am_ = model_(f,3:(L+2));
 
     maskdB_ = 20*log10(Am_);
     mask_sample_freqs_kHz = (1:L)*Wo*4/pi;
+    %maskdB_ = mask_model(maskdB_, Wo, L);
 
     if decimate_in_time
       % decimate mask samples in time
-      maskdB_ = decimate_frame_rate(maskdB_, model_, 4, f, frames, mask_sample_freqs_kHz);
+      maskdB_ = decimate_frame_rate(model_, 4, f, frames, mask_sample_freqs_kHz);
+
+      % find turning points - prototype for finding PF freqs when we decimate in time
+
+      d = maskdB_(2:L) - maskdB_(1:L-1);
+      tp = [];
+      for m=1:L-2
+        if (d(m) > 0) && (d(m+1) < 0)
+          tp = [tp m+1];
+        end
+      end
+      a_non_masked_m = tp;
+    else
+      % read non-maksed (PF freqs) from analysis stage
+      % number of non-masked samples is variable when not using AbyS,
+      % but fixed when using AbyS
+
+      m = max(find(non_masked_m(f,:) > 0)); 
+      a_non_masked_m = non_masked_m(f,1:m);
+
     end
 
     % post filter - bump up samples by 6dB, reduce mask by same level to normalise gain
 
     if postfilter
+
+      % Apply post filter - enhances formants, suppresses others, as pe Part 1 blog
+      % Pretty simple but makes a big difference
+
       maskdB_pf = maskdB_ - 6;
-      m = max(find(non_masked_m(f,:) > 0));
-      a_non_masked_m = non_masked_m(f,1:m);
       maskdB_pf(a_non_masked_m) = maskdB_pf(a_non_masked_m) + 6;
+
+      Am_ = zeros(1,max_amp);
+      Am_ = 10 .^ (maskdB_pf(1:L-1)/20); 
+      model_(f,3:(L+1)) = Am_;
     else
       maskdB_pf = maskdB_;
     end
@@ -122,15 +154,33 @@ function [non_masked_f_log non_masked_amp_log] = newamp_batch(samname, optional_
     fwrite(fam, Am_, "float32");
 
     if synth_phase
+
       % synthesis phase spectra from magnitiude spectra using minimum phase techniques
+
       fft_enc = 512;
-      model_(f,3:(L+2)) = 10 .^ (maskdB_pf(1:L)/20);
+      model_(f,3:(L+2)) = 10 .^ (maskdB_(1:L)/20);
       phase = determine_phase(model_, f);
       assert(length(phase) == fft_enc);
       Aw = zeros(1, fft_enc*2); 
       Aw(1:2:fft_enc*2) = cos(phase);
       Aw(2:2:fft_enc*2) = -sin(phase);
- 
+
+      if 0
+         % optional plotting to ensure amd and phase aligned on a few frames
+         figure(1)
+         clf;
+         subplot(211)
+         plot(mask_sample_freqs_kHz, maskdB_);
+         hold on;
+         plot(mask_sample_freqs_kHz, maskdB_pf,'g');
+         hold off;
+         axis([0 4 0 70])
+
+         subplot(212)
+         plot((0:(fft_enc/2)-1)*8000/fft_enc, phase(1:fft_enc/2))
+         axis([0 4000 -pi pi])
+         k = kbhit();         
+      end 
       fwrite(faw, Aw, "float32");    
     end
   end

diff --git a/codec2-dev/octave/newamp_fbf.m b/codec2-dev/octave/newamp_fbf.m
index aeea6163449d7cc9051afa21564daa546256bb33..9a4463b576f0446bb32bf60a33f764706830ad46 100644 (file)
--- a/codec2-dev/octave/newamp_fbf.m
+++ b/codec2-dev/octave/newamp_fbf.m
@@ -69,7 +69,6 @@ function newamp_fbf(samname, f=10)
     end
 
     [maskdB Am_freqs_kHz] = mask_model(AmdB, Wo, L);
-    [maskdB2 Am_freqs_kHz2] = mask_model(maskdB, Wo, L);
 
     %plot(Am_freqs_kHz*1000, maskdB, 'g');
     %plot(Am_freqs_kHz2*1000, maskdB2, 'r');
@@ -84,9 +83,17 @@ function newamp_fbf(samname, f=10)
 
     % decimate in frequency
 
-    if 1
     mask_sample_freqs_kHz = (1:L)*Wo*4/pi;
     [decmaskdB masker_freqs_kHz min_error mse_log1 mse_log2] = make_decmask_abys(maskdB, AmdB, Wo, L, mask_sample_freqs_kHz, freq_quant, amp_quant);
+
+    % find turning points - prototype for finding PF freqs when we decimate in time
+    
+    d = decmaskdB(2:L) - decmaskdB(1:L-1);
+    tp = [];
+    for m=1:L-1
+      if (d(m) > 0) && (d(m+1) < 0)
+        tp = [tp m+1];
+      end
     end
 
     figure(2)
@@ -94,10 +101,9 @@ function newamp_fbf(samname, f=10)
     tonef_kHz = masker_freqs_kHz;
     nlm = length(tonef_kHz);
 
-    if 1
     plot(tonef_kHz*1000, zeros(1,nlm), ';AbyS Mask Freqs;bk+');
     plot(mask_sample_freqs_kHz*1000, decmaskdB, ';AbyS Mask;m');
-    end
+    plot(tp*Wo*4000/pi, 5*ones(1,length(tp)), ';PF Freqs;r+');
     legend('boxoff');
     %plot(mask_sample_freqs_kHz*1000, min_error);
     hold off;