ref: 4a275d4d8f77afa8d308c2e9998bb5843944ac8c
dir: /libcelt/celt.c/
/* Copyright (c) 2007-2008 CSIRO
Copyright (c) 2007-2009 Xiph.Org Foundation
Copyright (c) 2008 Gregory Maxwell
Written by Jean-Marc Valin and Gregory Maxwell */
/*
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
- Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
- Neither the name of the Xiph.org Foundation nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#define CELT_C
#include "os_support.h"
#include "mdct.h"
#include <math.h>
#include "celt.h"
#include "pitch.h"
#include "kiss_fftr.h"
#include "bands.h"
#include "modes.h"
#include "entcode.h"
#include "quant_bands.h"
#include "psy.h"
#include "rate.h"
#include "stack_alloc.h"
#include "mathops.h"
#include "float_cast.h"
#include <stdarg.h>
static const celt_word16 preemph = QCONST16(0.8f,15);
#ifdef FIXED_POINT
static const celt_word16 transientWindow[16] = {
279, 1106, 2454, 4276, 6510, 9081, 11900, 14872,
17896, 20868, 23687, 26258, 28492, 30314, 31662, 32489};
#else
static const float transientWindow[16] = {
0.0085135, 0.0337639, 0.0748914, 0.1304955,
0.1986827, 0.2771308, 0.3631685, 0.4538658,
0.5461342, 0.6368315, 0.7228692, 0.8013173,
0.8695045, 0.9251086, 0.9662361, 0.9914865};
#endif
#define ENCODERVALID 0x4c434554
#define ENCODERPARTIAL 0x5445434c
#define ENCODERFREED 0x4c004500
/** Encoder state
@brief Encoder state
*/
struct CELTEncoder {
celt_uint32 marker;
const CELTMode *mode; /**< Mode used by the encoder */
int frame_size;
int block_size;
int overlap;
int channels;
int pitch_enabled; /* Complexity level is allowed to use pitch */
int pitch_permitted; /* Use of the LTP is permitted by the user */
int pitch_available; /* Amount of pitch buffer available */
int force_intra;
int delayedIntra;
celt_word16 tonal_average;
int fold_decision;
celt_word16 gain_prod;
/* VBR-related parameters */
celt_int32 vbr_reservoir;
celt_int32 vbr_drift;
celt_int32 vbr_offset;
celt_int32 vbr_count;
celt_int32 vbr_rate; /* Target number of 16th bits per frame */
celt_word16 * restrict preemph_memE;
celt_sig * restrict preemph_memD;
celt_sig *in_mem;
celt_sig *out_mem;
celt_word16 *oldBandE;
#ifdef EXP_PSY
celt_word16 *psy_mem;
struct PsyDecay psy;
#endif
};
static int check_encoder(const CELTEncoder *st)
{
if (st==NULL)
{
celt_warning("NULL passed as an encoder structure");
return CELT_INVALID_STATE;
}
if (st->marker == ENCODERVALID)
return CELT_OK;
if (st->marker == ENCODERFREED)
celt_warning("Referencing an encoder that has already been freed");
else
celt_warning("This is not a valid CELT encoder structure");
return CELT_INVALID_STATE;
}
CELTEncoder *celt_encoder_create(const CELTMode *mode, int channels, int *error)
{
int N, C;
CELTEncoder *st;
if (check_mode(mode) != CELT_OK)
{
if (error)
*error = CELT_INVALID_MODE;
return NULL;
}
#ifdef DISABLE_STEREO
if (channels > 1)
{
celt_warning("Stereo support was disable from this build");
if (error)
*error = CELT_BAD_ARG;
return NULL;
}
#endif
if (channels < 0 || channels > 2)
{
celt_warning("Only mono and stereo supported");
if (error)
*error = CELT_BAD_ARG;
return NULL;
}
N = mode->mdctSize;
C = channels;
st = celt_alloc(sizeof(CELTEncoder));
if (st==NULL)
{
if (error)
*error = CELT_ALLOC_FAIL;
return NULL;
}
st->marker = ENCODERPARTIAL;
st->mode = mode;
st->frame_size = N;
st->block_size = N;
st->overlap = mode->overlap;
st->channels = channels;
st->vbr_rate = 0;
st->pitch_enabled = 1;
st->pitch_permitted = 1;
st->pitch_available = 1;
st->force_intra = 0;
st->delayedIntra = 1;
st->tonal_average = QCONST16(1.,8);
st->fold_decision = 1;
st->in_mem = celt_alloc(st->overlap*C*sizeof(celt_sig));
st->out_mem = celt_alloc((MAX_PERIOD+st->overlap)*C*sizeof(celt_sig));
st->oldBandE = (celt_word16*)celt_alloc(C*mode->nbEBands*sizeof(celt_word16));
st->preemph_memE = (celt_word16*)celt_alloc(C*sizeof(celt_word16));
st->preemph_memD = (celt_sig*)celt_alloc(C*sizeof(celt_sig));
#ifdef EXP_PSY
st->psy_mem = celt_alloc(MAX_PERIOD*sizeof(celt_word16));
psydecay_init(&st->psy, MAX_PERIOD/2, st->mode->Fs);
#endif
if ((st->in_mem!=NULL) && (st->out_mem!=NULL) && (st->oldBandE!=NULL)
#ifdef EXP_PSY
&& (st->psy_mem!=NULL)
#endif
&& (st->preemph_memE!=NULL) && (st->preemph_memD!=NULL))
{
if (error)
*error = CELT_OK;
st->marker = ENCODERVALID;
return st;
}
/* If the setup fails for some reason deallocate it. */
celt_encoder_destroy(st);
if (error)
*error = CELT_ALLOC_FAIL;
return NULL;
}
void celt_encoder_destroy(CELTEncoder *st)
{
if (st == NULL)
{
celt_warning("NULL passed to celt_encoder_destroy");
return;
}
if (st->marker == ENCODERFREED)
{
celt_warning("Freeing an encoder which has already been freed");
return;
}
if (st->marker != ENCODERVALID && st->marker != ENCODERPARTIAL)
{
celt_warning("This is not a valid CELT encoder structure");
return;
}
/*Check_mode is non-fatal here because we can still free
the encoder memory even if the mode is bad, although calling
the free functions in this order is a violation of the API.*/
check_mode(st->mode);
celt_free(st->in_mem);
celt_free(st->out_mem);
celt_free(st->oldBandE);
celt_free(st->preemph_memE);
celt_free(st->preemph_memD);
#ifdef EXP_PSY
celt_free (st->psy_mem);
psydecay_clear(&st->psy);
#endif
st->marker = ENCODERFREED;
celt_free(st);
}
static inline celt_int16 FLOAT2INT16(float x)
{
x = x*CELT_SIG_SCALE;
x = MAX32(x, -32768);
x = MIN32(x, 32767);
return (celt_int16)float2int(x);
}
static inline celt_word16 SIG2WORD16(celt_sig x)
{
#ifdef FIXED_POINT
x = PSHR32(x, SIG_SHIFT);
x = MAX32(x, -32768);
x = MIN32(x, 32767);
return EXTRACT16(x);
#else
return (celt_word16)x;
#endif
}
static int transient_analysis(celt_word32 *in, int len, int C, int *transient_time, int *transient_shift)
{
int c, i, n;
celt_word32 ratio;
VARDECL(celt_word32, begin);
SAVE_STACK;
ALLOC(begin, len, celt_word32);
for (i=0;i<len;i++)
begin[i] = ABS32(SHR32(in[C*i],SIG_SHIFT));
for (c=1;c<C;c++)
{
for (i=0;i<len;i++)
begin[i] = MAX32(begin[i], ABS32(SHR32(in[C*i+c],SIG_SHIFT)));
}
for (i=1;i<len;i++)
begin[i] = MAX32(begin[i-1],begin[i]);
n = -1;
for (i=8;i<len-8;i++)
{
if (begin[i] < MULT16_32_Q15(QCONST16(.2f,15),begin[len-1]))
n=i;
}
if (n<32)
{
n = -1;
ratio = 0;
} else {
ratio = DIV32(begin[len-1],1+begin[n-16]);
}
if (ratio < 0)
ratio = 0;
if (ratio > 1000)
ratio = 1000;
ratio *= ratio;
if (ratio > 2048)
*transient_shift = 3;
else
*transient_shift = 0;
*transient_time = n;
RESTORE_STACK;
return ratio > 20;
}
/** Apply window and compute the MDCT for all sub-frames and
all channels in a frame */
static void compute_mdcts(const CELTMode *mode, int shortBlocks, celt_sig * restrict in, celt_sig * restrict out, int _C)
{
const int C = CHANNELS(_C);
if (C==1 && !shortBlocks)
{
const mdct_lookup *lookup = MDCT(mode);
const int overlap = OVERLAP(mode);
mdct_forward(lookup, in, out, mode->window, overlap);
} else {
const mdct_lookup *lookup = MDCT(mode);
const int overlap = OVERLAP(mode);
int N = FRAMESIZE(mode);
int B = 1;
int b, c;
VARDECL(celt_word32, x);
VARDECL(celt_word32, tmp);
SAVE_STACK;
if (shortBlocks)
{
lookup = &mode->shortMdct;
N = mode->shortMdctSize;
B = mode->nbShortMdcts;
}
ALLOC(x, N+overlap, celt_word32);
ALLOC(tmp, N, celt_word32);
for (c=0;c<C;c++)
{
for (b=0;b<B;b++)
{
int j;
for (j=0;j<N+overlap;j++)
x[j] = in[C*(b*N+j)+c];
mdct_forward(lookup, x, tmp, mode->window, overlap);
/* Interleaving the sub-frames */
for (j=0;j<N;j++)
out[(j*B+b)+c*N*B] = tmp[j];
}
}
RESTORE_STACK;
}
}
/** Compute the IMDCT and apply window for all sub-frames and
all channels in a frame */
static void compute_inv_mdcts(const CELTMode *mode, int shortBlocks, celt_sig *X, int transient_time, int transient_shift, celt_sig * restrict out_mem, int _C)
{
int c, N4;
const int C = CHANNELS(_C);
const int N = FRAMESIZE(mode);
const int overlap = OVERLAP(mode);
N4 = (N-overlap)>>1;
for (c=0;c<C;c++)
{
int j;
if (transient_shift==0 && C==1 && !shortBlocks) {
const mdct_lookup *lookup = MDCT(mode);
mdct_backward(lookup, X, out_mem+C*(MAX_PERIOD-N-N4), mode->window, overlap);
} else {
VARDECL(celt_word32, x);
VARDECL(celt_word32, tmp);
int b;
int N2 = N;
int B = 1;
int n4offset=0;
const mdct_lookup *lookup = MDCT(mode);
SAVE_STACK;
ALLOC(x, 2*N, celt_word32);
ALLOC(tmp, N, celt_word32);
if (shortBlocks)
{
lookup = &mode->shortMdct;
N2 = mode->shortMdctSize;
B = mode->nbShortMdcts;
n4offset = N4;
}
/* Prevents problems from the imdct doing the overlap-add */
CELT_MEMSET(x+N4, 0, N2);
for (b=0;b<B;b++)
{
/* De-interleaving the sub-frames */
for (j=0;j<N2;j++)
tmp[j] = X[(j*B+b)+c*N2*B];
mdct_backward(lookup, tmp, x+n4offset+N2*b, mode->window, overlap);
}
if (transient_shift > 0)
{
#ifdef FIXED_POINT
for (j=0;j<16;j++)
x[N4+transient_time+j-16] = MULT16_32_Q15(SHR16(Q15_ONE-transientWindow[j],transient_shift)+transientWindow[j], SHL32(x[N4+transient_time+j-16],transient_shift));
for (j=transient_time;j<N+overlap;j++)
x[N4+j] = SHL32(x[N4+j], transient_shift);
#else
for (j=0;j<16;j++)
x[N4+transient_time+j-16] *= 1+transientWindow[j]*((1<<transient_shift)-1);
for (j=transient_time;j<N+overlap;j++)
x[N4+j] *= 1<<transient_shift;
#endif
}
/* The first and last part would need to be set to zero
if we actually wanted to use them. */
for (j=0;j<overlap;j++)
out_mem[C*(MAX_PERIOD-N)+C*j+c] += x[j+N4];
for (j=0;j<overlap;j++)
out_mem[C*(MAX_PERIOD)+C*(overlap-j-1)+c] = x[2*N-j-N4-1];
for (j=0;j<2*N4;j++)
out_mem[C*(MAX_PERIOD-N)+C*(j+overlap)+c] = x[j+N4+overlap];
RESTORE_STACK;
}
}
}
#define FLAG_NONE 0
#define FLAG_INTRA (1U<<13)
#define FLAG_PITCH (1U<<12)
#define FLAG_SHORT (1U<<11)
#define FLAG_FOLD (1U<<10)
#define FLAG_MASK (FLAG_INTRA|FLAG_PITCH|FLAG_SHORT|FLAG_FOLD)
static const int flaglist[8] = {
0 /*00 */ | FLAG_FOLD,
1 /*01 */ | FLAG_PITCH|FLAG_FOLD,
8 /*1000*/ | FLAG_NONE,
9 /*1001*/ | FLAG_SHORT|FLAG_FOLD,
10 /*1010*/ | FLAG_PITCH,
11 /*1011*/ | FLAG_INTRA,
6 /*110 */ | FLAG_INTRA|FLAG_FOLD,
7 /*111 */ | FLAG_INTRA|FLAG_SHORT|FLAG_FOLD
};
static void encode_flags(ec_enc *enc, int intra_ener, int has_pitch, int shortBlocks, int has_fold)
{
int i;
int flags=FLAG_NONE;
int flag_bits;
flags |= intra_ener ? FLAG_INTRA : 0;
flags |= has_pitch ? FLAG_PITCH : 0;
flags |= shortBlocks ? FLAG_SHORT : 0;
flags |= has_fold ? FLAG_FOLD : 0;
for (i=0;i<8;i++)
if (flags == (flaglist[i]&FLAG_MASK))
break;
celt_assert(i<8);
flag_bits = flaglist[i]&0xf;
/*printf ("enc %d: %d %d %d %d\n", flag_bits, intra_ener, has_pitch, shortBlocks, has_fold);*/
if (i<2)
ec_enc_uint(enc, flag_bits, 4);
else if (i<6)
ec_enc_uint(enc, flag_bits, 16);
else
ec_enc_uint(enc, flag_bits, 8);
}
static void decode_flags(ec_dec *dec, int *intra_ener, int *has_pitch, int *shortBlocks, int *has_fold)
{
int i;
int flag_bits;
flag_bits = ec_dec_uint(dec, 4);
/*printf ("(%d) ", flag_bits);*/
if (flag_bits==2)
flag_bits = (flag_bits<<2) | ec_dec_uint(dec, 4);
else if (flag_bits==3)
flag_bits = (flag_bits<<1) | ec_dec_uint(dec, 2);
for (i=0;i<8;i++)
if (flag_bits == (flaglist[i]&0xf))
break;
celt_assert(i<8);
*intra_ener = (flaglist[i]&FLAG_INTRA) != 0;
*has_pitch = (flaglist[i]&FLAG_PITCH) != 0;
*shortBlocks = (flaglist[i]&FLAG_SHORT) != 0;
*has_fold = (flaglist[i]&FLAG_FOLD ) != 0;
/*printf ("dec %d: %d %d %d %d\n", flag_bits, *intra_ener, *has_pitch, *shortBlocks, *has_fold);*/
}
static void deemphasis(celt_sig *in, celt_word16 *pcm, int N, int _C, celt_word16 coef, celt_sig *mem)
{
const int C = CHANNELS(_C);
int c;
for (c=0;c<C;c++)
{
int j;
for (j=0;j<N;j++)
{
celt_sig tmp = MAC16_32_Q15(in[C*(MAX_PERIOD-N)+C*j+c],
coef,mem[c]);
mem[c] = tmp;
pcm[C*j+c] = SCALEOUT(SIG2WORD16(tmp));
}
}
}
static void mdct_shape(const CELTMode *mode, celt_norm *X, int start, int end, int N, int nbShortMdcts, int mdct_weight_shift, int _C)
{
int m, i, c;
const int C = CHANNELS(_C);
for (c=0;c<C;c++)
for (m=start;m<end;m++)
for (i=m+c*N;i<(c+1)*N;i+=nbShortMdcts)
#ifdef FIXED_POINT
X[i] = SHR16(X[i], mdct_weight_shift);
#else
X[i] = (1.f/(1<<mdct_weight_shift))*X[i];
#endif
renormalise_bands(mode, X, C);
}
#ifdef FIXED_POINT
int celt_encode(CELTEncoder * restrict st, const celt_int16 * pcm, celt_int16 * optional_synthesis, unsigned char *compressed, int nbCompressedBytes)
{
#else
int celt_encode_float(CELTEncoder * restrict st, const celt_sig * pcm, celt_sig * optional_synthesis, unsigned char *compressed, int nbCompressedBytes)
{
#endif
int i, c, N, NN, N4;
int has_pitch;
int pitch_index;
int bits;
int has_fold=1;
unsigned coarse_needed;
ec_byte_buffer buf;
ec_enc enc;
VARDECL(celt_sig, in);
VARDECL(celt_sig, freq);
VARDECL(celt_sig, pitch_freq);
VARDECL(celt_norm, X);
VARDECL(celt_ener, bandE);
VARDECL(celt_word16, bandLogE);
VARDECL(int, fine_quant);
VARDECL(celt_word16, error);
VARDECL(int, pulses);
VARDECL(int, offsets);
VARDECL(int, fine_priority);
int intra_ener = 0;
int shortBlocks=0;
int transient_time;
int transient_shift;
const int C = CHANNELS(st->channels);
int mdct_weight_shift = 0;
int mdct_weight_pos=0;
int gain_id=0;
int norm_rate;
SAVE_STACK;
if (check_encoder(st) != CELT_OK)
return CELT_INVALID_STATE;
if (check_mode(st->mode) != CELT_OK)
return CELT_INVALID_MODE;
if (nbCompressedBytes<0 || pcm==NULL)
return CELT_BAD_ARG;
/* The memset is important for now in case the encoder doesn't
fill up all the bytes */
CELT_MEMSET(compressed, 0, nbCompressedBytes);
ec_byte_writeinit_buffer(&buf, compressed, nbCompressedBytes);
ec_enc_init(&enc,&buf);
N = st->block_size;
N4 = (N-st->overlap)>>1;
ALLOC(in, 2*C*N-2*C*N4, celt_sig);
CELT_COPY(in, st->in_mem, C*st->overlap);
for (c=0;c<C;c++)
{
const celt_word16 * restrict pcmp = pcm+c;
celt_sig * restrict inp = in+C*st->overlap+c;
for (i=0;i<N;i++)
{
/* Apply pre-emphasis */
celt_sig tmp = SCALEIN(SHL32(EXTEND32(*pcmp), SIG_SHIFT));
*inp = SUB32(tmp, SHR32(MULT16_16(preemph,st->preemph_memE[c]),3));
st->preemph_memE[c] = SCALEIN(*pcmp);
inp += C;
pcmp += C;
}
}
CELT_COPY(st->in_mem, in+C*(2*N-2*N4-st->overlap), C*st->overlap);
/* Transient handling */
transient_time = -1;
transient_shift = 0;
shortBlocks = 0;
if (st->mode->nbShortMdcts > 1 && transient_analysis(in, N+st->overlap, C, &transient_time, &transient_shift))
{
#ifndef FIXED_POINT
float gain_1;
#endif
/* Apply the inverse shaping window */
if (transient_shift)
{
#ifdef FIXED_POINT
for (c=0;c<C;c++)
for (i=0;i<16;i++)
in[C*(transient_time+i-16)+c] = MULT16_32_Q15(EXTRACT16(SHR32(celt_rcp(Q15ONE+MULT16_16(transientWindow[i],((1<<transient_shift)-1))),1)), in[C*(transient_time+i-16)+c]);
for (c=0;c<C;c++)
for (i=transient_time;i<N+st->overlap;i++)
in[C*i+c] = SHR32(in[C*i+c], transient_shift);
#else
for (c=0;c<C;c++)
for (i=0;i<16;i++)
in[C*(transient_time+i-16)+c] /= 1+transientWindow[i]*((1<<transient_shift)-1);
gain_1 = 1./(1<<transient_shift);
for (c=0;c<C;c++)
for (i=transient_time;i<N+st->overlap;i++)
in[C*i+c] *= gain_1;
#endif
}
shortBlocks = 1;
has_fold = 1;
}
ALLOC(freq, C*N, celt_sig); /**< Interleaved signal MDCTs */
ALLOC(bandE,st->mode->nbEBands*C, celt_ener);
ALLOC(bandLogE,st->mode->nbEBands*C, celt_word16);
/* Compute MDCTs */
compute_mdcts(st->mode, shortBlocks, in, freq, C);
norm_rate = (nbCompressedBytes-5)*8*(celt_uint32)st->mode->Fs/(C*N)>>10;
/* Pitch analysis: we do it early to save on the peak stack space */
/* Don't use pitch if there isn't enough data available yet,
or if we're using shortBlocks */
has_pitch = st->pitch_enabled && st->pitch_permitted && (N <= 512)
&& (st->pitch_available >= MAX_PERIOD) && (!shortBlocks)
&& norm_rate < 50;
if (has_pitch)
{
find_spectral_pitch(st->mode, st->mode->fft, &st->mode->psy, in, st->out_mem, st->mode->window, NULL, 2*N-2*N4, MAX_PERIOD-(2*N-2*N4), &pitch_index, C);
}
/* Deferred allocation after find_spectral_pitch() to reduce
the peak memory usage */
ALLOC(X, C*N, celt_norm); /**< Interleaved normalised MDCTs */
ALLOC(pitch_freq, C*N, celt_sig); /**< Interleaved signal MDCTs */
if (has_pitch)
{
compute_mdcts(st->mode, 0, st->out_mem+pitch_index*C, pitch_freq, C);
has_pitch = compute_pitch_gain(st->mode, freq, pitch_freq, norm_rate, &gain_id, C, &st->gain_prod);
}
if (has_pitch)
apply_pitch(st->mode, freq, pitch_freq, gain_id, 1, C);
compute_band_energies(st->mode, freq, bandE, C);
for (i=0;i<st->mode->nbEBands*C;i++)
bandLogE[i] = amp2Log(bandE[i]);
/* Band normalisation */
normalise_bands(st->mode, freq, X, bandE, C);
if (!shortBlocks && !folding_decision(st->mode, X, &st->tonal_average, &st->fold_decision, C))
has_fold = 0;
/* Don't use intra energy when we're operating at low bit-rate */
intra_ener = st->force_intra || (!has_pitch && st->delayedIntra && nbCompressedBytes > st->mode->nbEBands);
if (shortBlocks || intra_decision(bandLogE, st->oldBandE, st->mode->nbEBands))
st->delayedIntra = 1;
else
st->delayedIntra = 0;
NN = st->mode->eBands[st->mode->nbEBands];
if (shortBlocks && !transient_shift)
{
celt_word32 sum[8]={1,1,1,1,1,1,1,1};
int m;
for (c=0;c<C;c++)
{
m=0;
do {
celt_word32 tmp=0;
for (i=m+c*N;i<c*N+NN;i+=st->mode->nbShortMdcts)
tmp += ABS32(X[i]);
sum[m++] += tmp;
} while (m<st->mode->nbShortMdcts);
}
m=0;
#ifdef FIXED_POINT
do {
if (SHR32(sum[m+1],3) > sum[m])
{
mdct_weight_shift=2;
mdct_weight_pos = m;
} else if (SHR32(sum[m+1],1) > sum[m] && mdct_weight_shift < 2)
{
mdct_weight_shift=1;
mdct_weight_pos = m;
}
m++;
} while (m<st->mode->nbShortMdcts-1);
#else
do {
if (sum[m+1] > 8*sum[m])
{
mdct_weight_shift=2;
mdct_weight_pos = m;
} else if (sum[m+1] > 2*sum[m] && mdct_weight_shift < 2)
{
mdct_weight_shift=1;
mdct_weight_pos = m;
}
m++;
} while (m<st->mode->nbShortMdcts-1);
#endif
if (mdct_weight_shift)
{
mdct_shape(st->mode, X, mdct_weight_pos+1, st->mode->nbShortMdcts, N, st->mode->nbShortMdcts, mdct_weight_shift, C);
renormalise_bands(st->mode, X, C);
}
}
encode_flags(&enc, intra_ener, has_pitch, shortBlocks, has_fold);
if (has_pitch)
{
ec_enc_uint(&enc, pitch_index, MAX_PERIOD-(2*N-2*N4));
ec_enc_uint(&enc, gain_id, 16);
}
if (shortBlocks)
{
if (transient_shift)
{
ec_enc_uint(&enc, transient_shift, 4);
ec_enc_uint(&enc, transient_time, N+st->overlap);
} else {
ec_enc_uint(&enc, mdct_weight_shift, 4);
if (mdct_weight_shift && st->mode->nbShortMdcts!=2)
ec_enc_uint(&enc, mdct_weight_pos, st->mode->nbShortMdcts-1);
}
}
ALLOC(fine_quant, st->mode->nbEBands, int);
ALLOC(pulses, st->mode->nbEBands, int);
/* Bit allocation */
ALLOC(error, C*st->mode->nbEBands, celt_word16);
coarse_needed = quant_coarse_energy(st->mode, bandLogE, st->oldBandE, nbCompressedBytes*8/3, intra_ener, st->mode->prob, error, &enc, C);
coarse_needed = ((coarse_needed*3-1)>>3)+1;
/* Variable bitrate */
if (st->vbr_rate>0)
{
celt_word16 alpha;
celt_int32 delta, vbr_bound;
/* The target rate in 16th bits per frame */
celt_int32 target=st->vbr_rate;
/* Shortblocks get a large boost in bitrate, but since they
are uncommon long blocks are not greatly effected */
if (shortBlocks)
target*=2;
else if (st->mode->nbShortMdcts > 1)
target-=(target+14)/28;
/* The average energy is removed from the target and the actual
energy added*/
target=target+st->vbr_offset-588+ec_enc_tell(&enc, BITRES);
/* In VBR mode the frame size must not be reduced so much that it would result in the coarse energy busting its budget */
target=IMAX(coarse_needed,(target+64)/128);
nbCompressedBytes=IMIN(nbCompressedBytes,target);
/* Make the adaptation coef (alpha) higher at the beginning */
if (st->vbr_count < 990)
{
st->vbr_count++;
alpha = celt_rcp(SHL32(EXTEND32(st->vbr_count+10),16));
/*printf ("%d %d\n", st->vbr_count+10, alpha);*/
} else
alpha = QCONST16(.001f,15);
/* By how much did we "miss" the target on that frame */
delta = (8<<BITRES)*(celt_int32)nbCompressedBytes - st->vbr_rate;
/* How many bits have we used in excess of what we're allowed */
st->vbr_reservoir += delta;
/*printf ("%d\n", st->vbr_reservoir);*/
/* Compute the offset we need to apply in order to reach the target */
st->vbr_drift += MULT16_32_Q15(alpha,delta-st->vbr_offset-st->vbr_drift);
st->vbr_offset = -st->vbr_drift;
/*printf ("%d\n", st->vbr_drift);*/
/* We could use any multiple of vbr_rate as bound (depending on the delay) */
vbr_bound = st->vbr_rate;
if (st->vbr_reservoir > vbr_bound)
{
/* Busted the reservoir -- reduce the rate */
int adjust = 1+(st->vbr_reservoir-vbr_bound-1)/(8<<BITRES);
nbCompressedBytes -= adjust;
st->vbr_reservoir -= adjust*(8<<BITRES);
st->vbr_offset -= 8<<BITRES;
/*printf ("-%d\n", adjust);*/
} else if (st->vbr_reservoir < 0)
{
/* We're under the min value -- increase rate */
int adjust = 1-(st->vbr_reservoir-1)/(8<<BITRES);
st->vbr_reservoir += adjust*(8<<BITRES);
nbCompressedBytes += adjust;
st->vbr_offset += 8<<BITRES;
/*printf ("+%d\n", adjust);*/
}
/* This moves the raw bits to take into account the new compressed size */
ec_byte_shrink(&buf, nbCompressedBytes);
}
ALLOC(offsets, st->mode->nbEBands, int);
ALLOC(fine_priority, st->mode->nbEBands, int);
for (i=0;i<st->mode->nbEBands;i++)
offsets[i] = 0;
bits = nbCompressedBytes*8 - ec_enc_tell(&enc, 0) - 1;
compute_allocation(st->mode, offsets, bits, pulses, fine_quant, fine_priority, C);
quant_fine_energy(st->mode, bandE, st->oldBandE, error, fine_quant, &enc, C);
/* Residual quantisation */
if (C==1)
quant_bands(st->mode, X, bandE, pulses, shortBlocks, has_fold, nbCompressedBytes*8, 1, &enc);
#ifndef DISABLE_STEREO
else
quant_bands_stereo(st->mode, X, bandE, pulses, shortBlocks, has_fold, nbCompressedBytes*8, &enc);
#endif
quant_energy_finalise(st->mode, bandE, st->oldBandE, error, fine_quant, fine_priority, nbCompressedBytes*8-ec_enc_tell(&enc, 0), &enc, C);
/* Re-synthesis of the coded audio if required */
if (st->pitch_available>0 || optional_synthesis!=NULL)
{
if (st->pitch_available>0 && st->pitch_available<MAX_PERIOD)
st->pitch_available+=st->frame_size;
if (mdct_weight_shift)
{
mdct_shape(st->mode, X, 0, mdct_weight_pos+1, N, st->mode->nbShortMdcts, mdct_weight_shift, C);
}
/* Synthesis */
denormalise_bands(st->mode, X, freq, bandE, C);
CELT_MOVE(st->out_mem, st->out_mem+C*N, C*(MAX_PERIOD+st->overlap-N));
if (has_pitch)
apply_pitch(st->mode, freq, pitch_freq, gain_id, 0, C);
compute_inv_mdcts(st->mode, shortBlocks, freq, transient_time, transient_shift, st->out_mem, C);
/* De-emphasis and put everything back at the right place
in the synthesis history */
if (optional_synthesis != NULL) {
deemphasis(st->out_mem, optional_synthesis, N, C, preemph, st->preemph_memD);
}
}
ec_enc_done(&enc);
RESTORE_STACK;
return nbCompressedBytes;
}
#ifdef FIXED_POINT
#ifndef DISABLE_FLOAT_API
int celt_encode_float(CELTEncoder * restrict st, const float * pcm, float * optional_synthesis, unsigned char *compressed, int nbCompressedBytes)
{
int j, ret, C, N;
VARDECL(celt_int16, in);
SAVE_STACK;
if (check_encoder(st) != CELT_OK)
return CELT_INVALID_STATE;
if (check_mode(st->mode) != CELT_OK)
return CELT_INVALID_MODE;
if (pcm==NULL)
return CELT_BAD_ARG;
C = CHANNELS(st->channels);
N = st->block_size;
ALLOC(in, C*N, celt_int16);
for (j=0;j<C*N;j++)
in[j] = FLOAT2INT16(pcm[j]);
if (optional_synthesis != NULL) {
ret=celt_encode(st,in,in,compressed,nbCompressedBytes);
for (j=0;j<C*N;j++)
optional_synthesis[j]=in[j]*(1/32768.);
} else {
ret=celt_encode(st,in,NULL,compressed,nbCompressedBytes);
}
RESTORE_STACK;
return ret;
}
#endif /*DISABLE_FLOAT_API*/
#else
int celt_encode(CELTEncoder * restrict st, const celt_int16 * pcm, celt_int16 * optional_synthesis, unsigned char *compressed, int nbCompressedBytes)
{
int j, ret, C, N;
VARDECL(celt_sig, in);
SAVE_STACK;
if (check_encoder(st) != CELT_OK)
return CELT_INVALID_STATE;
if (check_mode(st->mode) != CELT_OK)
return CELT_INVALID_MODE;
if (pcm==NULL)
return CELT_BAD_ARG;
C=CHANNELS(st->channels);
N=st->block_size;
ALLOC(in, C*N, celt_sig);
for (j=0;j<C*N;j++) {
in[j] = SCALEOUT(pcm[j]);
}
if (optional_synthesis != NULL) {
ret = celt_encode_float(st,in,in,compressed,nbCompressedBytes);
for (j=0;j<C*N;j++)
optional_synthesis[j] = FLOAT2INT16(in[j]);
} else {
ret = celt_encode_float(st,in,NULL,compressed,nbCompressedBytes);
}
RESTORE_STACK;
return ret;
}
#endif
int celt_encoder_ctl(CELTEncoder * restrict st, int request, ...)
{
va_list ap;
if (check_encoder(st) != CELT_OK)
return CELT_INVALID_STATE;
va_start(ap, request);
if ((request!=CELT_GET_MODE_REQUEST) && (check_mode(st->mode) != CELT_OK))
goto bad_mode;
switch (request)
{
case CELT_GET_MODE_REQUEST:
{
const CELTMode ** value = va_arg(ap, const CELTMode**);
if (value==0)
goto bad_arg;
*value=st->mode;
}
break;
case CELT_SET_COMPLEXITY_REQUEST:
{
int value = va_arg(ap, celt_int32);
if (value<0 || value>10)
goto bad_arg;
if (value<=2) {
st->pitch_enabled = 0;
st->pitch_available = 0;
} else {
st->pitch_enabled = 1;
if (st->pitch_available<1)
st->pitch_available = 1;
}
}
break;
case CELT_SET_PREDICTION_REQUEST:
{
int value = va_arg(ap, celt_int32);
if (value<0 || value>2)
goto bad_arg;
if (value==0)
{
st->force_intra = 1;
st->pitch_permitted = 0;
} else if (value==1) {
st->force_intra = 0;
st->pitch_permitted = 0;
} else {
st->force_intra = 0;
st->pitch_permitted = 1;
}
}
break;
case CELT_SET_VBR_RATE_REQUEST:
{
celt_int32 value = va_arg(ap, celt_int32);
if (value<0)
goto bad_arg;
if (value>3072000)
value = 3072000;
st->vbr_rate = ((st->mode->Fs<<3)+(st->block_size>>1))/st->block_size;
st->vbr_rate = ((value<<7)+(st->vbr_rate>>1))/st->vbr_rate;
}
break;
case CELT_RESET_STATE:
{
const CELTMode *mode = st->mode;
int C = st->channels;
if (st->pitch_available > 0) st->pitch_available = 1;
CELT_MEMSET(st->in_mem, 0, st->overlap*C);
CELT_MEMSET(st->out_mem, 0, (MAX_PERIOD+st->overlap)*C);
CELT_MEMSET(st->oldBandE, 0, C*mode->nbEBands);
CELT_MEMSET(st->preemph_memE, 0, C);
CELT_MEMSET(st->preemph_memD, 0, C);
st->delayedIntra = 1;
}
break;
default:
goto bad_request;
}
va_end(ap);
return CELT_OK;
bad_mode:
va_end(ap);
return CELT_INVALID_MODE;
bad_arg:
va_end(ap);
return CELT_BAD_ARG;
bad_request:
va_end(ap);
return CELT_UNIMPLEMENTED;
}
/**********************************************************************/
/* */
/* DECODER */
/* */
/**********************************************************************/
#ifdef NEW_PLC
#define DECODE_BUFFER_SIZE 2048
#else
#define DECODE_BUFFER_SIZE MAX_PERIOD
#endif
#define DECODERVALID 0x4c434454
#define DECODERPARTIAL 0x5444434c
#define DECODERFREED 0x4c004400
/** Decoder state
@brief Decoder state
*/
struct CELTDecoder {
celt_uint32 marker;
const CELTMode *mode;
int frame_size;
int block_size;
int overlap;
int channels;
ec_byte_buffer buf;
ec_enc enc;
celt_sig * restrict preemph_memD;
celt_sig *out_mem;
celt_sig *decode_mem;
celt_word16 *oldBandE;
int last_pitch_index;
int loss_count;
};
int check_decoder(const CELTDecoder *st)
{
if (st==NULL)
{
celt_warning("NULL passed a decoder structure");
return CELT_INVALID_STATE;
}
if (st->marker == DECODERVALID)
return CELT_OK;
if (st->marker == DECODERFREED)
celt_warning("Referencing a decoder that has already been freed");
else
celt_warning("This is not a valid CELT decoder structure");
return CELT_INVALID_STATE;
}
CELTDecoder *celt_decoder_create(const CELTMode *mode, int channels, int *error)
{
int N, C;
CELTDecoder *st;
if (check_mode(mode) != CELT_OK)
{
if (error)
*error = CELT_INVALID_MODE;
return NULL;
}
#ifdef DISABLE_STEREO
if (channels > 1)
{
celt_warning("Stereo support was disable from this build");
if (error)
*error = CELT_BAD_ARG;
return NULL;
}
#endif
if (channels < 0 || channels > 2)
{
celt_warning("Only mono and stereo supported");
if (error)
*error = CELT_BAD_ARG;
return NULL;
}
N = mode->mdctSize;
C = CHANNELS(channels);
st = celt_alloc(sizeof(CELTDecoder));
if (st==NULL)
{
if (error)
*error = CELT_ALLOC_FAIL;
return NULL;
}
st->marker = DECODERPARTIAL;
st->mode = mode;
st->frame_size = N;
st->block_size = N;
st->overlap = mode->overlap;
st->channels = channels;
st->decode_mem = celt_alloc((DECODE_BUFFER_SIZE+st->overlap)*C*sizeof(celt_sig));
st->out_mem = st->decode_mem+DECODE_BUFFER_SIZE-MAX_PERIOD;
st->oldBandE = (celt_word16*)celt_alloc(C*mode->nbEBands*sizeof(celt_word16));
st->preemph_memD = (celt_sig*)celt_alloc(C*sizeof(celt_sig));
st->loss_count = 0;
if ((st->decode_mem!=NULL) && (st->out_mem!=NULL) && (st->oldBandE!=NULL) &&
(st->preemph_memD!=NULL))
{
if (error)
*error = CELT_OK;
st->marker = DECODERVALID;
return st;
}
/* If the setup fails for some reason deallocate it. */
celt_decoder_destroy(st);
if (error)
*error = CELT_ALLOC_FAIL;
return NULL;
}
void celt_decoder_destroy(CELTDecoder *st)
{
if (st == NULL)
{
celt_warning("NULL passed to celt_decoder_destroy");
return;
}
if (st->marker == DECODERFREED)
{
celt_warning("Freeing a decoder which has already been freed");
return;
}
if (st->marker != DECODERVALID && st->marker != DECODERPARTIAL)
{
celt_warning("This is not a valid CELT decoder structure");
return;
}
/*Check_mode is non-fatal here because we can still free
the encoder memory even if the mode is bad, although calling
the free functions in this order is a violation of the API.*/
check_mode(st->mode);
celt_free(st->decode_mem);
celt_free(st->oldBandE);
celt_free(st->preemph_memD);
st->marker = DECODERFREED;
celt_free(st);
}
/** Handles lost packets by just copying past data with the same
offset as the last
pitch period */
#ifdef NEW_PLC
#include "plc.c"
#else
static void celt_decode_lost(CELTDecoder * restrict st, celt_word16 * restrict pcm)
{
int c, N;
int pitch_index;
celt_word16 fade = Q15ONE;
int i, len;
VARDECL(celt_sig, freq);
const int C = CHANNELS(st->channels);
int offset;
SAVE_STACK;
N = st->block_size;
ALLOC(freq,C*N, celt_sig); /**< Interleaved signal MDCTs */
len = N+st->mode->overlap;
if (st->loss_count == 0)
{
find_spectral_pitch(st->mode, st->mode->fft, &st->mode->psy, st->out_mem+MAX_PERIOD-len, st->out_mem, st->mode->window, NULL, len, MAX_PERIOD-len-100, &pitch_index, C);
pitch_index = MAX_PERIOD-len-pitch_index;
st->last_pitch_index = pitch_index;
} else {
pitch_index = st->last_pitch_index;
if (st->loss_count < 5)
fade = QCONST16(.8f,15);
else
fade = 0;
}
offset = MAX_PERIOD-pitch_index;
while (offset+len >= MAX_PERIOD)
offset -= pitch_index;
compute_mdcts(st->mode, 0, st->out_mem+offset*C, freq, C);
for (i=0;i<C*N;i++)
freq[i] = ADD32(VERY_SMALL, MULT16_32_Q15(fade,freq[i]));
CELT_MOVE(st->out_mem, st->out_mem+C*N, C*(MAX_PERIOD+st->mode->overlap-N));
/* Compute inverse MDCTs */
compute_inv_mdcts(st->mode, 0, freq, -1, 0, st->out_mem, C);
for (c=0;c<C;c++)
{
int j;
for (j=0;j<N;j++)
{
celt_sig tmp = MAC16_32_Q15(st->out_mem[C*(MAX_PERIOD-N)+C*j+c],
preemph,st->preemph_memD[c]);
st->preemph_memD[c] = tmp;
pcm[C*j+c] = SCALEOUT(SIG2WORD16(tmp));
}
}
st->loss_count++;
RESTORE_STACK;
}
#endif
#ifdef FIXED_POINT
int celt_decode(CELTDecoder * restrict st, const unsigned char *data, int len, celt_int16 * restrict pcm)
{
#else
int celt_decode_float(CELTDecoder * restrict st, const unsigned char *data, int len, celt_sig * restrict pcm)
{
#endif
int i, N, N4;
int has_pitch, has_fold;
int pitch_index;
int bits;
ec_dec dec;
ec_byte_buffer buf;
VARDECL(celt_sig, freq);
VARDECL(celt_sig, pitch_freq);
VARDECL(celt_norm, X);
VARDECL(celt_ener, bandE);
VARDECL(int, fine_quant);
VARDECL(int, pulses);
VARDECL(int, offsets);
VARDECL(int, fine_priority);
int shortBlocks;
int intra_ener;
int transient_time;
int transient_shift;
int mdct_weight_shift=0;
const int C = CHANNELS(st->channels);
int mdct_weight_pos=0;
int gain_id=0;
SAVE_STACK;
if (check_decoder(st) != CELT_OK)
return CELT_INVALID_STATE;
if (check_mode(st->mode) != CELT_OK)
return CELT_INVALID_MODE;
if (pcm==NULL)
return CELT_BAD_ARG;
N = st->block_size;
N4 = (N-st->overlap)>>1;
ALLOC(freq, C*N, celt_sig); /**< Interleaved signal MDCTs */
ALLOC(X, C*N, celt_norm); /**< Interleaved normalised MDCTs */
ALLOC(bandE, st->mode->nbEBands*C, celt_ener);
if (data == NULL)
{
celt_decode_lost(st, pcm);
RESTORE_STACK;
return 0;
} else {
st->loss_count = 0;
}
if (len<0) {
RESTORE_STACK;
return CELT_BAD_ARG;
}
ec_byte_readinit(&buf,(unsigned char*)data,len);
ec_dec_init(&dec,&buf);
decode_flags(&dec, &intra_ener, &has_pitch, &shortBlocks, &has_fold);
if (shortBlocks)
{
transient_shift = ec_dec_uint(&dec, 4);
if (transient_shift == 3)
{
transient_time = ec_dec_uint(&dec, N+st->mode->overlap);
} else {
mdct_weight_shift = transient_shift;
if (mdct_weight_shift && st->mode->nbShortMdcts>2)
mdct_weight_pos = ec_dec_uint(&dec, st->mode->nbShortMdcts-1);
transient_shift = 0;
transient_time = 0;
}
} else {
transient_time = -1;
transient_shift = 0;
}
if (has_pitch)
{
pitch_index = ec_dec_uint(&dec, MAX_PERIOD-(2*N-2*N4));
gain_id = ec_dec_uint(&dec, 16);
} else {
pitch_index = 0;
}
ALLOC(fine_quant, st->mode->nbEBands, int);
/* Get band energies */
unquant_coarse_energy(st->mode, bandE, st->oldBandE, len*8/3, intra_ener, st->mode->prob, &dec, C);
ALLOC(pulses, st->mode->nbEBands, int);
ALLOC(offsets, st->mode->nbEBands, int);
ALLOC(fine_priority, st->mode->nbEBands, int);
for (i=0;i<st->mode->nbEBands;i++)
offsets[i] = 0;
bits = len*8 - ec_dec_tell(&dec, 0) - 1;
compute_allocation(st->mode, offsets, bits, pulses, fine_quant, fine_priority, C);
/*bits = ec_dec_tell(&dec, 0);
compute_fine_allocation(st->mode, fine_quant, (20*C+len*8/5-(ec_dec_tell(&dec, 0)-bits))/C);*/
unquant_fine_energy(st->mode, bandE, st->oldBandE, fine_quant, &dec, C);
ALLOC(pitch_freq, C*N, celt_sig); /**< Interleaved signal MDCTs */
if (has_pitch)
{
/* Pitch MDCT */
compute_mdcts(st->mode, 0, st->out_mem+pitch_index*C, pitch_freq, C);
}
/* Decode fixed codebook and merge with pitch */
if (C==1)
quant_bands(st->mode, X, bandE, pulses, shortBlocks, has_fold, len*8, 0, &dec);
#ifndef DISABLE_STEREO
else
unquant_bands_stereo(st->mode, X, bandE, pulses, shortBlocks, has_fold, len*8, &dec);
#endif
unquant_energy_finalise(st->mode, bandE, st->oldBandE, fine_quant, fine_priority, len*8-ec_dec_tell(&dec, 0), &dec, C);
if (mdct_weight_shift)
{
mdct_shape(st->mode, X, 0, mdct_weight_pos+1, N, st->mode->nbShortMdcts, mdct_weight_shift, C);
}
/* Synthesis */
denormalise_bands(st->mode, X, freq, bandE, C);
CELT_MOVE(st->decode_mem, st->decode_mem+C*N, C*(DECODE_BUFFER_SIZE+st->overlap-N));
if (has_pitch)
apply_pitch(st->mode, freq, pitch_freq, gain_id, 0, C);
/* Compute inverse MDCTs */
compute_inv_mdcts(st->mode, shortBlocks, freq, transient_time, transient_shift, st->out_mem, C);
deemphasis(st->out_mem, pcm, N, C, preemph, st->preemph_memD);
RESTORE_STACK;
return 0;
}
#ifdef FIXED_POINT
#ifndef DISABLE_FLOAT_API
int celt_decode_float(CELTDecoder * restrict st, const unsigned char *data, int len, float * restrict pcm)
{
int j, ret, C, N;
VARDECL(celt_int16, out);
SAVE_STACK;
if (check_decoder(st) != CELT_OK)
return CELT_INVALID_STATE;
if (check_mode(st->mode) != CELT_OK)
return CELT_INVALID_MODE;
if (pcm==NULL)
return CELT_BAD_ARG;
C = CHANNELS(st->channels);
N = st->block_size;
ALLOC(out, C*N, celt_int16);
ret=celt_decode(st, data, len, out);
for (j=0;j<C*N;j++)
pcm[j]=out[j]*(1/32768.);
RESTORE_STACK;
return ret;
}
#endif /*DISABLE_FLOAT_API*/
#else
int celt_decode(CELTDecoder * restrict st, const unsigned char *data, int len, celt_int16 * restrict pcm)
{
int j, ret, C, N;
VARDECL(celt_sig, out);
SAVE_STACK;
if (check_decoder(st) != CELT_OK)
return CELT_INVALID_STATE;
if (check_mode(st->mode) != CELT_OK)
return CELT_INVALID_MODE;
if (pcm==NULL)
return CELT_BAD_ARG;
C = CHANNELS(st->channels);
N = st->block_size;
ALLOC(out, C*N, celt_sig);
ret=celt_decode_float(st, data, len, out);
for (j=0;j<C*N;j++)
pcm[j] = FLOAT2INT16 (out[j]);
RESTORE_STACK;
return ret;
}
#endif
int celt_decoder_ctl(CELTDecoder * restrict st, int request, ...)
{
va_list ap;
if (check_decoder(st) != CELT_OK)
return CELT_INVALID_STATE;
va_start(ap, request);
if ((request!=CELT_GET_MODE_REQUEST) && (check_mode(st->mode) != CELT_OK))
goto bad_mode;
switch (request)
{
case CELT_GET_MODE_REQUEST:
{
const CELTMode ** value = va_arg(ap, const CELTMode**);
if (value==0)
goto bad_arg;
*value=st->mode;
}
break;
case CELT_RESET_STATE:
{
const CELTMode *mode = st->mode;
int C = st->channels;
CELT_MEMSET(st->decode_mem, 0, (DECODE_BUFFER_SIZE+st->overlap)*C);
CELT_MEMSET(st->oldBandE, 0, C*mode->nbEBands);
CELT_MEMSET(st->preemph_memD, 0, C);
st->loss_count = 0;
}
break;
default:
goto bad_request;
}
va_end(ap);
return CELT_OK;
bad_mode:
va_end(ap);
return CELT_INVALID_MODE;
bad_arg:
va_end(ap);
return CELT_BAD_ARG;
bad_request:
va_end(ap);
return CELT_UNIMPLEMENTED;
}
const char *celt_strerror(int error)
{
static const char *error_strings[8] = {
"success",
"invalid argument",
"invalid mode",
"internal error",
"corrupted stream",
"request not implemented",
"invalid state",
"memory allocation failed"
};
if (error > 0 || error < -7)
return "unknown error";
else
return error_strings[-error];
}