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Added decoder code (not working yet)

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This commit is contained in:
Jean-Marc Valin 2007-12-07 11:29:45 +11:00
parent bb57fe44e2
commit 269d40a5c0
3 changed files with 153 additions and 10 deletions
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143
libcelt/celt.c
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@ -41,7 +41,7 @@
#define MAX_PERIOD 1024
struct CELTState {
struct CELTEncoder {
const CELTMode *mode;
int frame_size;
int block_size;
@ -67,12 +67,12 @@ struct CELTState {
CELTState *celt_encoder_new(const CELTMode *mode)
CELTEncoder *celt_encoder_new(const CELTMode *mode)
{
int i, N, B;
N = mode->mdctSize;
B = mode->nbMdctBlocks;
CELTState *st = celt_alloc(sizeof(CELTState));
CELTEncoder *st = celt_alloc(sizeof(CELTEncoder));
st->mode = mode;
st->frame_size = B*N;
@ -97,7 +97,7 @@ CELTState *celt_encoder_new(const CELTMode *mode)
return st;
}
void celt_encoder_destroy(CELTState *st)
void celt_encoder_destroy(CELTEncoder *st)
{
if (st == NULL)
{
@ -162,7 +162,7 @@ static void compute_mdcts(mdct_lookup *mdct_lookup, float *window, float *in, fl
}
int celt_encode(CELTState *st, short *pcm)
int celt_encode(CELTEncoder *st, short *pcm)
{
int i, N, B;
N = st->block_size;
@ -278,3 +278,136 @@ int celt_encode(CELTState *st, short *pcm)
return 0;
}
/****************************************************************************/
/* Decoder */
/****************************************************************************/
struct CELTDecoder {
const CELTMode *mode;
int frame_size;
int block_size;
int nb_blocks;
ec_byte_buffer buf;
ec_enc enc;
float preemph;
float preemph_memD;
mdct_lookup mdct_lookup;
float *window;
float *mdct_overlap;
float *out_mem;
float *oldBandE;
};
CELTDecoder *celt_decoder_new(const CELTMode *mode)
{
int i, N, B;
N = mode->mdctSize;
B = mode->nbMdctBlocks;
CELTDecoder *st = celt_alloc(sizeof(CELTDecoder));
st->mode = mode;
st->frame_size = B*N;
st->block_size = N;
st->nb_blocks = B;
ec_byte_writeinit(&st->buf);
mdct_init(&st->mdct_lookup, 2*N);
st->window = celt_alloc(2*N*sizeof(float));
st->mdct_overlap = celt_alloc(N*sizeof(float));
st->out_mem = celt_alloc(MAX_PERIOD*sizeof(float));
for (i=0;i<N;i++)
st->window[i] = st->window[2*N-i-1] = sin(.5*M_PI* sin(.5*M_PI*(i+.5)/N) * sin(.5*M_PI*(i+.5)/N));
st->oldBandE = celt_alloc(mode->nbEBands*sizeof(float));
st->preemph = 0.8;
return st;
}
void celt_decoder_destroy(CELTDecoder *st)
{
if (st == NULL)
{
celt_warning("NULL passed to celt_encoder_destroy");
return;
}
mdct_clear(&st->mdct_lookup);
celt_free(st->window);
celt_free(st->mdct_overlap);
celt_free(st->out_mem);
celt_free(st->oldBandE);
celt_free(st);
}
int celt_decode(CELTDecoder *st, short *pcm)
{
int i, N, B;
N = st->block_size;
B = st->nb_blocks;
float X[B*N]; /**< Interleaved signal MDCTs */
float P[B*N]; /**< Interleaved pitch MDCTs*/
float bandE[st->mode->nbEBands];
float gains[st->mode->nbPBands];
int pitch_index;
compute_mdcts(&st->mdct_lookup, st->window, st->out_mem+pitch_index, P, N, B);
//haar1(P, B*N);
{
float bandEp[st->mode->nbEBands];
compute_band_energies(st->mode, P, bandEp);
normalise_bands(st->mode, P, bandEp);
}
/* Apply pitch gains */
/* Decode fixed codebook */
/* Merge pitch and fixed codebook */
/* Synthesis */
denormalise_bands(st->mode, X, bandE);
//inv_haar1(X, B*N);
CELT_MOVE(st->out_mem, st->out_mem+B*N, MAX_PERIOD-B*N);
/* Compute inverse MDCTs */
for (i=0;i<B;i++)
{
int j;
float x[2*N];
float tmp[N];
/* De-interleaving the sub-frames */
for (j=0;j<N;j++)
tmp[j] = X[B*j+i];
mdct_backward(&st->mdct_lookup, tmp, x);
for (j=0;j<2*N;j++)
x[j] = st->window[j]*x[j];
for (j=0;j<N;j++)
st->out_mem[MAX_PERIOD+(i-B)*N+j] = x[j]+st->mdct_overlap[j];
for (j=0;j<N;j++)
st->mdct_overlap[j] = x[N+j];
for (j=0;j<N;j++)
{
float tmp = st->out_mem[MAX_PERIOD+(i-B)*N+j] + st->preemph*st->preemph_memD;
st->preemph_memD = tmp;
pcm[i*N+j] = (short)floor(.5+tmp);
}
}
}