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Vorbis optimizations: allocation of PCM buffers in IRAM, avoiding copying.

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Slight code improvements to the MDCT functions.


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@6590 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Pedro Vasconcelos 2005-06-06 23:01:51 +00:00
parent 127f14210f
commit 0f10e898f0
11 changed files with 110 additions and 132 deletions
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27
apps/codecs/Tremor/synthesis.c
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@ -24,6 +24,17 @@
#include "misc.h"
#include "os.h"
/* IRAM buffer keep the block pcm data; only for windows size upto 2048
for space restrictions. No real compromise, larger window sizes
are only used for very low quality settings (q<0?) */
/* max 2 channels on the ihp-1xx (stereo), 2048 samples (2*2048*4=16Kb) */
#define IRAM_PCM_END 2048
#define CHANNELS 2
static ogg_int32_t *ipcm_vect[CHANNELS] IDATA_ATTR;
static ogg_int32_t ipcm_buff[CHANNELS*IRAM_PCM_END] IDATA_ATTR;
int vorbis_synthesis(vorbis_block *vb,ogg_packet *op,int decodep){
vorbis_dsp_state *vd=vb->vd;
private_state *b=(private_state *)vd->backend_state;
@ -65,10 +76,18 @@ int vorbis_synthesis(vorbis_block *vb,ogg_packet *op,int decodep){
if(decodep){
/* alloc pcm passback storage */
vb->pcmend=ci->blocksizes[vb->W];
vb->pcm=(ogg_int32_t **)_vorbis_block_alloc(vb,sizeof(*vb->pcm)*vi->channels);
for(i=0;i<vi->channels;i++)
vb->pcm[i]=(ogg_int32_t *)_vorbis_block_alloc(vb,vb->pcmend*sizeof(*vb->pcm[i]));
if (vi->channels <= CHANNELS && vb->pcmend<=IRAM_PCM_END) {
/* use statically allocated iram buffer */
vb->pcm = ipcm_vect;
for(i=0; i<CHANNELS; i++)
vb->pcm[i] = &ipcm_buff[i*IRAM_PCM_END];
} else {
/* dynamic allocation (slower) */
vb->pcm=(ogg_int32_t **)_vorbis_block_alloc(vb,sizeof(*vb->pcm)*vi->channels);
for(i=0;i<vi->channels;i++)
vb->pcm[i]=(ogg_int32_t *)_vorbis_block_alloc(vb,vb->pcmend*sizeof(*vb->pcm[i]));
}
/* unpack_header enforces range checking */
type=ci->map_type[ci->mode_param[mode]->mapping];