Fix FS#10174 by correcting an oversimplification of the AAC window switching code I introduced with the unified IMDCT library. Should significantly improve accuracy for all AAC files.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@20821 a1c6a512-1295-4272-9138-f99709370657

3 files changed, 24 insertions, 9 deletions

diff --git a/apps/codecs/libfaad/filtbank.c b/apps/codecs/libfaad/filtbank.c
index e5c1bd3870..90175d953c 100644
--- a/apps/codecs/libfaad/filtbank.c
+++ b/apps/codecs/libfaad/filtbank.c
@@ -198,8 +198,8 @@ static INLINE void mdct(fb_info *fb, real_t *in_data, real_t *out_data, uint16_t
 
 ALIGN real_t transf_buf[2*1024] IBSS_ATTR;
 
-void ifilter_bank(uint8_t window_sequence,
-                  real_t *freq_in,
+void ifilter_bank(uint8_t window_sequence, uint8_t window_shape,
+                  uint8_t window_shape_prev, real_t *freq_in,
                   real_t *time_out, real_t *overlap,
                   uint8_t object_type, uint16_t frame_len)
 {
@@ -232,10 +232,22 @@ void ifilter_bank(uint8_t window_sequence,
         (void) object_type;
 #endif
 
-        window_long       = sine_long_1024;
+    /*AAC uses two different window shapes depending on spectal features*/
+    if(window_shape == 0){
+        window_long  = sine_long_1024;
+        window_short = sine_short_128;
+    } else {
+        window_long  = kbd_long_1024;
+        window_short = kbd_short_128;            
+    }
+    
+    if(window_shape_prev == 0){
+        window_long_prev  = sine_long_1024;
+        window_short_prev = sine_short_128;
+    } else {
         window_long_prev  = kbd_long_1024;
-        window_short      = sine_short_128;
         window_short_prev = kbd_short_128;
+    }
 
 #ifdef LD_DEC
     }
diff --git a/apps/codecs/libfaad/filtbank.h b/apps/codecs/libfaad/filtbank.h
index 24c6017a35..8c9f1e3490 100644
--- a/apps/codecs/libfaad/filtbank.h
+++ b/apps/codecs/libfaad/filtbank.h
@@ -43,8 +43,8 @@ void filter_bank_ltp(fb_info *fb,
                      uint16_t frame_len);
 #endif
 
-void ifilter_bank(uint8_t window_sequence, 
-                  real_t *freq_in,
+void ifilter_bank(uint8_t window_sequence,  uint8_t window_shape,
+                  uint8_t window_shape_prev, real_t *freq_in,
                   real_t *time_out, real_t *overlap,
                   uint8_t object_type, uint16_t frame_len);
 
diff --git a/apps/codecs/libfaad/specrec.c b/apps/codecs/libfaad/specrec.c
index de57c4b7ce..4998828eff 100644
--- a/apps/codecs/libfaad/specrec.c
+++ b/apps/codecs/libfaad/specrec.c
@@ -960,7 +960,8 @@ uint8_t reconstruct_single_channel(NeAACDecHandle hDecoder, ic_stream *ics,
     if (hDecoder->object_type != SSR)
     {
 #endif
-        ifilter_bank(ics->window_sequence,spec_coef,
+        ifilter_bank(ics->window_sequence,ics->window_shape,
+            hDecoder->window_shape_prev[sce->channel],spec_coef,
             hDecoder->time_out[sce->channel], hDecoder->fb_intermed[sce->channel],
             hDecoder->object_type, hDecoder->frameLength);
 #ifdef SSR_DEC
@@ -1198,10 +1199,12 @@ uint8_t reconstruct_channel_pair(NeAACDecHandle hDecoder, ic_stream *ics1, ic_st
     if (hDecoder->object_type != SSR)
     {
 #endif
-        ifilter_bank(ics1->window_sequence, spec_coef1,
+        ifilter_bank(ics1->window_sequence,ics1->window_shape, 
+            hDecoder->window_shape_prev[cpe->channel],spec_coef1,
             hDecoder->time_out[cpe->channel], hDecoder->fb_intermed[cpe->channel],
             hDecoder->object_type, hDecoder->frameLength);
-        ifilter_bank(ics2->window_sequence,spec_coef2,
+        ifilter_bank(ics2->window_sequence,ics2->window_shape,
+            hDecoder->window_shape_prev[cpe->paired_channel], spec_coef2,
             hDecoder->time_out[cpe->paired_channel], hDecoder->fb_intermed[cpe->paired_channel],
             hDecoder->object_type, hDecoder->frameLength);
 #ifdef SSR_DEC