From 1c25bbc96121f10cd1a6756d06faddf64da6de7e Mon Sep 17 00:00:00 2001
From: drowe67 <drowe67@01035d8c-6547-0410-b346-abe4f91aad63>
Date: Fri, 11 Aug 2017 07:47:14 +0000
Subject: [PATCH] reas results with 2 bit slope and 1 bit mag quantiser 1-3k,
 with dec by 4, and refactored to quantiser callbacks

git-svn-id: https://svn.code.sf.net/p/freetel/code@3352 01035d8c-6547-0410-b346-abe4f91aad63
---
 codec2-dev/octave/closed_quant_slope.m |  3 +++
 codec2-dev/octave/open_quant_slope.m   |  4 ++++
 codec2-dev/octave/vq_search_slope.m    | 16 ++++++++++++----
 3 files changed, 19 insertions(+), 4 deletions(-)
 create mode 100644 codec2-dev/octave/closed_quant_slope.m
 create mode 100644 codec2-dev/octave/open_quant_slope.m

diff --git a/codec2-dev/octave/closed_quant_slope.m b/codec2-dev/octave/closed_quant_slope.m
new file mode 100644
index 00000000..7d5a465b
--- /dev/null
+++ b/codec2-dev/octave/closed_quant_slope.m
@@ -0,0 +1,3 @@
+function b = closed_quant_slope(b)
+  b(1) = max(0.5, b(1));
+end
diff --git a/codec2-dev/octave/open_quant_slope.m b/codec2-dev/octave/open_quant_slope.m
new file mode 100644
index 00000000..20965547
--- /dev/null
+++ b/codec2-dev/octave/open_quant_slope.m
@@ -0,0 +1,4 @@
+function b = open_quant_slope(b)
+  b(2) = quantise([-1 -0.5 0.5 1], b(2));
+  b(1) = quantise([0.5 1.0], b(1));
+end
diff --git a/codec2-dev/octave/vq_search_slope.m b/codec2-dev/octave/vq_search_slope.m
index f0c6cb82..7f4d3349 100644
--- a/codec2-dev/octave/vq_search_slope.m
+++ b/codec2-dev/octave/vq_search_slope.m
@@ -27,9 +27,9 @@ function [idx contrib errors b_log2] = vq_search_slope(vq, data, closed_quant_fn
     for i=1:nVec
       c = [sum(target) target*(1:nCols)' target*vq(i,:)' ]';
       b = inv(A(:,:,i))*c;
-      if nargin == 3;
+      if nargin >= 3;
         b = feval(closed_quant_fn,b);
-      end;  
+      end
       b_log(i,:) = b; 
       
       diff(i,:) = target - (b(1)*vq(i,:) + b(2)*(1:nCols) + b(3));
@@ -43,9 +43,17 @@ function [idx contrib errors b_log2] = vq_search_slope(vq, data, closed_quant_fn
     errors(f) = mn; 
     idx(f) = min_ind(1);
     b = b_log(min_ind,:);
-    b_log2(f,:) = b;
+
+    % optional quantisation performed after error min loop
+    % - note we recalc gain to match energy after quantisation
     
-    %printf("f: %d i: %d mg: %f sl: %f g: %f\n", f, idx(f), b(1), b(2), b(3));
+    if nargin == 4
+      b = feval(open_quant_fn, b);
+      b(3) = (sum(target) - sum(b(1)*vq(min_ind,:) + b(2)*(1:nCols)))/nCols;    
+    end
+
+    printf("f: %d i: %d mg: %f sl: %f g: %f\n", f, idx(f), b(1), b(2), b(3));
+    b_log2(f,:) = b;
     contrib(f,:) = b(1)*vq(min_ind,:) + b(2)*(1:nCols) + b(3);
   end
 
-- 
2.25.1