ref: 7a08ddd14ed87d271a15705c9c329bd3190cf4a0
parent: 35fceef3b42abfa1bc7c619dc2198e5fb53b1a17
author: Jean-Marc Valin <[email protected]>
date: Mon Oct 18 10:55:42 EDT 2010
Removing both the transient window and the mdct_weight_shift. Both ended up causing more harm than good (e.g. violating energy conservation) and provided little benefit. This also saves ~3 kB code size on x86-86.
--- a/libcelt/celt.c
+++ b/libcelt/celt.c
@@ -53,18 +53,6 @@
#include <stdarg.h>
#include "plc.h"
-#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] = {- 0.0085135f, 0.0337639f, 0.0748914f, 0.1304955f,
- 0.1986827f, 0.2771308f, 0.3631685f, 0.4538658f,
- 0.5461342f, 0.6368315f, 0.7228692f, 0.8013173f,
- 0.8695045f, 0.9251086f, 0.9662361f, 0.9914865f};
-#endif
-
static const int trim_cdf[7] = {0, 4, 10, 23, 119, 125, 128}; static const int trim_coef[6] = {4, 6, 7, 8, 10, 12};@@ -182,7 +170,6 @@
}
static int transient_analysis(const celt_word32 * restrict in, int len, int C,
- int *transient_time, int *transient_shift,
celt_word32 *frame_max, int overlap)
{int i, n;
@@ -249,12 +236,6 @@
ratio = DIV32(begin[len],1+MAX32(*frame_max, begin[n-16]));
}
- if (0&&ratio > 45)
- *transient_shift = 3;
- else
- *transient_shift = 0;
-
- *transient_time = n;
*frame_max = begin[len-overlap];
/* Only consider the last 7.5 ms for the next transient */
if (len>360+overlap)
@@ -312,7 +293,7 @@
/** 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[],
+ celt_sig * restrict out_mem[],
celt_sig * restrict overlap_mem[], int _C, int LM)
{int c;
@@ -348,20 +329,6 @@
clt_mdct_backward(&mode->mdct, tmp, x+N2*b, mode->window, overlap, shortBlocks ? mode->maxLM : mode->maxLM-LM);
}
- if (transient_shift > 0)
- {-#ifdef FIXED_POINT
- for (j=0;j<16;j++)
- x[transient_time+j-16] = MULT16_32_Q15(SHR16(Q15_ONE-transientWindow[j],transient_shift)+transientWindow[j], SHL32(x[transient_time+j-16],transient_shift));
- for (j=transient_time;j<N+overlap;j++)
- x[j] = SHL32(x[j], transient_shift);
-#else
- for (j=0;j<16;j++)
- x[transient_time+j-16] *= 1+transientWindow[j]*((1<<transient_shift)-1);
- for (j=transient_time;j<N+overlap;j++)
- x[j] *= 1<<transient_shift;
-#endif
- }
for (j=0;j<overlap;j++)
out_mem[c][j] = x[j] + overlap_mem[c][j];
for (;j<N;j++)
@@ -398,24 +365,6 @@
}
}
-static void mdct_shape(const CELTMode *mode, celt_norm *X, int start,
- int end, int N,
- int mdct_weight_shift, int end_band, int _C, int renorm, int M)
-{- 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+=M)
-#ifdef FIXED_POINT
- X[i] = SHR16(X[i], mdct_weight_shift);
-#else
- X[i] = (1.f/(1<<mdct_weight_shift))*X[i];
-#endif
- if (renorm)
- renormalise_bands(mode, X, end_band, C, M);
-}
-
static const signed char tf_select_table[4][8] = { {0, -1, 0, -1, 0,-1, 0,-1}, {0, -1, 0, -2, 1, 0, 1 -1},@@ -616,7 +565,7 @@
int celt_encode_with_ec_float(CELTEncoder * restrict st, const celt_sig * pcm, celt_sig * optional_resynthesis, int frame_size, unsigned char *compressed, int nbCompressedBytes, ec_enc *enc)
{#endif
- int i, c, N, NN;
+ int i, c, N;
int bits;
int has_fold=1;
ec_byte_buffer buf;
@@ -636,12 +585,8 @@
celt_word16 *oldBandE;
int shortBlocks=0;
int isTransient=0;
- int transient_time, transient_time_quant;
- int transient_shift;
int resynth;
const int C = CHANNELS(st->channels);
- int mdct_weight_shift = 0;
- int mdct_weight_pos=0;
int LM, M;
int tf_select;
int nbFilledBytes, nbAvailableBytes;
@@ -700,49 +645,15 @@
}
CELT_COPY(st->in_mem, in+C*N, C*st->overlap);
- /* Transient handling */
- transient_time = -1;
- transient_time_quant = -1;
- transient_shift = 0;
-
resynth = optional_resynthesis!=NULL;
if (st->complexity > 1 && LM>0)
{isTransient = M > 1 &&
- transient_analysis(in, N+st->overlap, C, &transient_time,
- &transient_shift, &st->frame_max, st->overlap);
+ transient_analysis(in, N+st->overlap, C, &st->frame_max, st->overlap);
} else {isTransient = 0;
}
- if (isTransient)
- {-#ifndef FIXED_POINT
- float gain_1;
-#endif
- /* Apply the inverse shaping window */
- if (transient_shift)
- {- transient_time_quant = transient_time*(celt_int32)8000/st->mode->Fs;
- transient_time = transient_time_quant*(celt_int32)st->mode->Fs/8000;
-#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.f/(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
- }
- }
if (isTransient)
shortBlocks = M;
@@ -770,53 +681,6 @@
for (i=effEnd;i<st->end;i++)
tf_res[i] = tf_res[effEnd-1];
- NN = M*st->mode->eBands[effEnd];
- 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+=M)
- tmp += ABS32(X[i]);
- sum[m++] += tmp;
- } while (m<M);
- }
- 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<M-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<M-1);
-#endif
- if (mdct_weight_shift)
- mdct_shape(st->mode, X, mdct_weight_pos+1, M, N, mdct_weight_shift, effEnd, C, 0, M);
- }
-
ALLOC(error, C*st->mode->nbEBands, celt_word16);
quant_coarse_energy(st->mode, st->start, st->end, effEnd, bandLogE,
oldBandE, nbCompressedBytes*8, st->mode->prob,
@@ -826,20 +690,6 @@
if (LM > 0)
ec_enc_bit_prob(enc, shortBlocks!=0, 8192);
- if (shortBlocks)
- {- if (transient_shift)
- {- int max_time = (N+st->mode->overlap)*(celt_int32)8000/st->mode->Fs;
- ec_enc_uint(enc, transient_shift, 4);
- ec_enc_uint(enc, transient_time_quant, max_time);
- } else {- ec_enc_uint(enc, mdct_weight_shift, 4);
- if (mdct_weight_shift && M!=2)
- ec_enc_uint(enc, mdct_weight_pos, M-1);
- }
- }
-
tf_encode(st->start, st->end, isTransient, tf_res, nbAvailableBytes, LM, tf_select, enc);
if (shortBlocks || st->complexity < 3)
@@ -1019,11 +869,6 @@
measure_norm_mse(st->mode, X, X0, bandE, bandE0, M, N, C);
#endif
- if (mdct_weight_shift)
- {- mdct_shape(st->mode, X, 0, mdct_weight_pos+1, N, mdct_weight_shift, effEnd, C, 1, M);
- }
-
/* Synthesis */
denormalise_bands(st->mode, X, freq, bandE, effEnd, C, M);
@@ -1042,8 +887,7 @@
out_mem[c] = _out_mem+c*N;
}
- compute_inv_mdcts(st->mode, shortBlocks, freq, transient_time,
- transient_shift, out_mem, overlap_mem, C, LM);
+ compute_inv_mdcts(st->mode, shortBlocks, freq, out_mem, overlap_mem, C, LM);
/* De-emphasis and put everything back at the right place
in the synthesis history */
@@ -1540,11 +1384,7 @@
int shortBlocks;
int isTransient;
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 LM, M;
int nbFilledBytes, nbAvailableBytes;
int effEnd;
@@ -1625,27 +1465,6 @@
else
shortBlocks = 0;
- if (isTransient)
- {- transient_shift = ec_dec_uint(dec, 4);
- if (transient_shift == 3)
- {- int transient_time_quant;
- int max_time = (N+st->mode->overlap)*(celt_int32)8000/st->mode->Fs;
- transient_time_quant = ec_dec_uint(dec, max_time);
- transient_time = transient_time_quant*(celt_int32)st->mode->Fs/8000;
- } else {- mdct_weight_shift = transient_shift;
- if (mdct_weight_shift && M>2)
- mdct_weight_pos = ec_dec_uint(dec, M-1);
- transient_shift = 0;
- transient_time = 0;
- }
- } else {- transient_time = -1;
- transient_shift = 0;
- }
-
ALLOC(tf_res, st->mode->nbEBands, int);
tf_decode(st->start, st->end, C, isTransient, tf_res, nbAvailableBytes, LM, dec);
@@ -1693,11 +1512,6 @@
log2Amp(st->mode, st->start, st->end, bandE, oldBandE, C);
- if (mdct_weight_shift)
- {- mdct_shape(st->mode, X, 0, mdct_weight_pos+1, N, mdct_weight_shift, effEnd, C, 1, M);
- }
-
/* Synthesis */
denormalise_bands(st->mode, X, freq, bandE, effEnd, C, M);
@@ -1717,8 +1531,7 @@
out_syn[1] = out_mem[1]+MAX_PERIOD-N;
/* Compute inverse MDCTs */
- compute_inv_mdcts(st->mode, shortBlocks, freq, transient_time,
- transient_shift, out_syn, overlap_mem, C, LM);
+ compute_inv_mdcts(st->mode, shortBlocks, freq, out_syn, overlap_mem, C, LM);
deemphasis(out_syn, pcm, N, C, st->mode->preemph, st->preemph_memD);
st->loss_count = 0;