Enabling "plain folding" in case we don't even have enough bits for intra-frame

prediction

1 files changed, 20 insertions, 8 deletions

diff --git a/libcelt/bands.c b/libcelt/bands.c
index 599e7fb..c7ffc10 100644
--- a/libcelt/bands.c
+++ b/libcelt/bands.c
@@ -259,10 +259,16 @@ void quant_bands(const CELTMode *m, float *X, float *P, float *W, struct alloc_d
       theta = .007*(B*(eBands[i+1]-eBands[i]))/(.1f+abs(q));
 
       /* If pitch isn't available, use intra-frame prediction */
-      if (eBands[i] >= m->pitchEnd)
-         intra_prediction(X+B*eBands[i], W+B*eBands[i], B*(eBands[i+1]-eBands[i]), q, norm, P+B*eBands[i], B, eBands[i], enc);
-
-      if (q != 0)
+      if (eBands[i] >= m->pitchEnd || q<=0)
+      {
+         q -= 1;
+         if (q<0)
+            intra_fold(X+B*eBands[i], B*(eBands[i+1]-eBands[i]), q, norm, P+B*eBands[i], B, eBands[i]);
+         else
+            intra_prediction(X+B*eBands[i], W+B*eBands[i], B*(eBands[i+1]-eBands[i]), q, norm, P+B*eBands[i], B, eBands[i], enc);
+      }
+      
+      if (q > 0)
       {
          exp_rotation(P+B*eBands[i], B*(eBands[i+1]-eBands[i]), theta, -1, B, 8);
          exp_rotation(X+B*eBands[i], B*(eBands[i+1]-eBands[i]), theta, -1, B, 8);
@@ -305,10 +311,16 @@ void unquant_bands(const CELTMode *m, float *X, float *P, struct alloc_data *all
       theta = .007*(B*(eBands[i+1]-eBands[i]))/(.1f+abs(q));
 
       /* If pitch isn't available, use intra-frame prediction */
-      if (eBands[i] >= m->pitchEnd)
-         intra_unquant(X+B*eBands[i], B*(eBands[i+1]-eBands[i]), q, norm, P+B*eBands[i], B, eBands[i], dec);
-
-      if (q != 0)
+      if (eBands[i] >= m->pitchEnd || q<=0)
+      {
+         q -= 1;
+         if (q<0)
+            intra_fold(X+B*eBands[i], B*(eBands[i+1]-eBands[i]), q, norm, P+B*eBands[i], B, eBands[i]);
+         else
+            intra_unquant(X+B*eBands[i], B*(eBands[i+1]-eBands[i]), q, norm, P+B*eBands[i], B, eBands[i], dec);
+      }
+      
+      if (q > 0)
       {
          exp_rotation(P+B*eBands[i], B*(eBands[i+1]-eBands[i]), theta, -1, B, 8);
          alg_unquant(X+B*eBands[i], B*(eBands[i+1]-eBands[i]), q, P+B*eBands[i], 0.7, dec);