libtremor: port over ffmpeg's windowing code

Use the windowing approach from ffmpeg in tremor, does the mdct doubling, windowing and overlap add in one go.
Also uses less memory so all the processing buffers fit in iram on targets with small iram for the common blocksizes (256/2048) now.

Speeds up decoding of vorbis files by 3MHz for 256/2048 and 20MHz for 512/4096 files on h300.
Speeds up decoding of vorbis files by 3MHz for 256/2048 and 4.5MHz for 512/4096 on the beast.
Speeds up decoding of vorbis files by 0.3MHz for 256/2048 and 1MHz for 512/4096 on c200v1.


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30580 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 12 insertions, 16 deletions

diff --git a/apps/codecs/libtremor/mapping0.c b/apps/codecs/libtremor/mapping0.c
index 9042b9c..084d5e0 100644
--- a/apps/codecs/libtremor/mapping0.c
+++ b/apps/codecs/libtremor/mapping0.c
@@ -302,7 +302,6 @@ static int mapping0_inverse(vorbis_block *vb,vorbis_look_mapping *l){
   vorbis_dsp_state     *vd=vb->vd;
   vorbis_info          *vi=vd->vi;
   codec_setup_info     *ci=(codec_setup_info *)vi->codec_setup;
-  private_state        *b=(private_state *)vd->backend_state;
   vorbis_look_mapping0 *look=(vorbis_look_mapping0 *)l;
   vorbis_info_mapping0 *info=look->map;
 
@@ -329,8 +328,8 @@ static int mapping0_inverse(vorbis_block *vb,vorbis_look_mapping *l){
     if(floormemo[i])
       nonzero[i]=1;
     else
-      nonzero[i]=0;      
-    memset(vb->pcm[i],0,sizeof(*vb->pcm[i])*n/2);
+      nonzero[i]=0;
+    memset(vd->floors + i * ci->blocksizes[vb->W]/2,0,sizeof(ogg_int32_t)*n/2);
   }
 
   /* channel coupling can 'dirty' the nonzero listing */
@@ -351,7 +350,7 @@ static int mapping0_inverse(vorbis_block *vb,vorbis_look_mapping *l){
           zerobundle[ch_in_bundle]=1;
         else
           zerobundle[ch_in_bundle]=0;
-        pcmbundle[ch_in_bundle++]=vb->pcm[j];
+        pcmbundle[ch_in_bundle++] = vd->floors + j * ci->blocksizes[vb->W]/2;
       }
     }
 
@@ -365,8 +364,8 @@ static int mapping0_inverse(vorbis_block *vb,vorbis_look_mapping *l){
 
   /* channel coupling */
   for(i=info->coupling_steps-1;i>=0;i--){
-    ogg_int32_t *pcmM=vb->pcm[info->coupling_mag[i]];
-    ogg_int32_t *pcmA=vb->pcm[info->coupling_ang[i]];
+    ogg_int32_t *pcmM = vd->floors + info->coupling_mag[i] * ci->blocksizes[vb->W]/2;
+    ogg_int32_t *pcmA = vd->floors + info->coupling_ang[i] * ci->blocksizes[vb->W]/2;
     channel_couple(pcmM,pcmA,n);
   }
 
@@ -378,24 +377,21 @@ static int mapping0_inverse(vorbis_block *vb,vorbis_look_mapping *l){
 
   /* transform the PCM data; takes PCM vector, vb; modifies PCM vector */
   /* only MDCT right now.... */
-
   for(i=0;i<vi->channels;i++){
-    ogg_int32_t *pcm=vb->pcm[i];
+    ogg_int32_t *pcm = vd->floors + i*ci->blocksizes[vb->W]/2;
     int submap=info->chmuxlist[i];
     
     if(nonzero[i]) {
       /* compute and apply spectral envelope */
       look->floor_func[submap]->
         inverse2(vb,look->floor_look[submap],floormemo[i],pcm);
-        
-      ff_imdct_calc(ci->blocksizes_nbits[vb->W],
-                    (int32_t*)pcm,
-                    (int32_t*)pcm);
-      /* window the data */
-      _vorbis_apply_window(pcm,b->window,ci->blocksizes,vb->lW,vb->W,vb->nW);
+
+      ff_imdct_half(ci->blocksizes_nbits[vb->W],
+                    (int32_t*)vd->residues[vd->ri] + i*ci->blocksizes[vb->W]/2,
+                    (int32_t*)&vd->floors[i*ci->blocksizes[vb->W]/2]);
     }
-    else 
-      memset(pcm, 0, sizeof(ogg_int32_t)*n);
+    else
+      memset(vd->residues[vd->ri] + i*ci->blocksizes[vb->W]/2, 0, sizeof(ogg_int32_t)*n/2);
   }
 
   //for(j=0;j<vi->channels;j++)