/*====================================================================================
EVS Codec 3GPP TS26.442 Jun 30, 2015. Version CR 26.442-0010
====================================================================================*/
#include <stdio.h>
#include "assert.h"
#include "stl.h"
#include "basop_mpy.h"
#include "cnst_fx.h"
#include "rom_com_fx.h"
#include "prot_fx.h"
/*---------------------------------------------------------------
* Ari decode 14 bits routines
-------------------------------------------------------------*/
Word16 ari_decode_overflow(TastatDec *s)
{
return L_sub(L_sub(s->high, 1), s->low) <= 0;
}
/**
* \brief Start ArCo decoding
*
* \param[i/o] st
* \param[o] s
*/
void ari_start_decoding_14bits(Decoder_State_fx *st, TastatDec *s)
{
Word32 val;
val = L_and(L_deposit_l(get_next_indice_fx(st, cbitsnew)), 0xffffL);
s->low = L_deposit_l(0);
s->high = ari_q4new+1;
move32();
s->vobf = val;
move32();
}
Word16 ari_start_decoding_14bits_prm(const Word16 *ptr, Word16 bp, TastatDec *s)
{
Word32 val;
Word16 i;
const Word16 *p;
val = L_deposit_l(0);
p = ptr+bp;
FOR (i=0; i<cbitsnew; i++)
{
val = L_shl(val, 1);
if (*(p+i))
{
val = L_add(val, 1);
}
}
s->low = L_deposit_l(0);
s->high = ari_q4new+1;
move32();
s->vobf = val;
move32();
return add(bp,i);
}
static Word16 ari_lookup_s17(Word32 cum, Word32 range, UWord16 const *cum_freq)
{
Word32 tmp;
const UWord16 *p;
Word16 range_l, range_h;
p = cum_freq;
/* Note: For each indirect addressing p[i], we assume a tmp pointer init followed by a costfree reading the value */
/* If the value multiplied by range is greater than cum, the pointer p is set to the tmp pointer */
/* tmp_p = p+8; if (tmp_p[0]*range>cum) p = tmp_p; */
/* max value in p[x] is 16384 => 14 bits */
range_l = extract_l(L_and(range,0x7FFF));
range_h = extract_l(L_shr(range,15));
tmp = L_multi31x16_X2(range_h, range_l,p[8]);
if (L_sub(tmp,cum) > 0)
{
p = p + 8;
}
tmp = L_multi31x16_X2(range_h, range_l,p[4]);
if (L_sub(tmp,cum) > 0)
{
p = p + 4;
}
tmp = L_multi31x16_X2(range_h, range_l,p[2]);
if (L_sub(tmp,cum) > 0)
{
p = p + 2;
}
tmp = L_multi31x16_X2(range_h, range_l,p[1]);
IF (L_sub(tmp,cum) > 0)
{
p = p + 1;
tmp = L_multi31x16_X2(range_h, range_l,p[1]);
test();
if ( ((Word32)(&cum_freq[15] - p) == 0) && (L_sub(tmp,cum) > 0) )
{
p = p + 1;
}
}
/* return extract_l(L_shr(L_sub((Word32)p,(Word32)cum_freq),1)); */
L_sub(0,0);
L_shr(0,0); /* pointer subtraction */
return extract_l(p - cum_freq);
}
static Word16 ari_lookup_s27(Word32 cum, Word32 range, UWord16 const *cum_freq)
{
Word32 tmp;
Word16 range_l, range_h;
Word16 il, ih, im;
/* Note: For each indirect addressing p[i], we assume a tmp pointer init followed by a costfree reading the value */
/* If the value multiplied by range is greater than cum, the pointer p is set to the tmp pointer */
/* tmp_p = p+8; if (tmp_p[0]*range>cum) p = tmp_p; */
/* max value in p[x] is 16384 => 14 bits */
range_l = extract_l(L_and(range,0x7FFF));
range_h = extract_l(L_shr(range,15));
/* begin change when compared with ari_decode_14bits_s17_ext,
starting with line: tmp = L_multi31x16_X2(range_h, range_l, p[8]); */
il = 0;
move16();
ih = 27;
move16();
/* do a five step binary search, using the interval [il, ih) */
im = 13;
move16(); /* (il + ih) >> 1 */
tmp = L_multi31x16_X2(range_h, range_l, cum_freq[im]);
tmp = L_sub(tmp, cum);
if (tmp > 0)
{
il = im;
move16();
}
if (tmp <= 0)
{
ih = im;
move16();
}
im = shr(add(il, ih), 1);
tmp = L_multi31x16_X2(range_h, range_l, cum_freq[im]);
tmp = L_sub(tmp, cum);
if (tmp > 0)
{
il = im;
move16();
}
if (tmp <= 0)
{
ih = im;
move16();
}
im = shr(add(il, ih), 1);
tmp = L_multi31x16_X2(range_h, range_l, cum_freq[im]);
tmp = L_sub(tmp, cum);
if (tmp > 0)
{
il = im;
move16();
}
if (tmp <= 0)
{
ih = im;
move16();
}
im = shr(add(il, ih), 1);
tmp = L_multi31x16_X2(range_h, range_l, cum_freq[im]);
tmp = L_sub(tmp, cum);
if (tmp > 0)
{
il = im;
move16();
}
if (tmp <= 0)
{
ih = im;
move16();
}
IF (sub(sub(ih, il), 1) > 0) /* if the interval has more than one symbol */
{
/* here, only ih == il + 2 is possible, which means two symbols in the interval */
im = add(il, 1); /* (il + ih) >> 1 */
tmp = L_multi31x16_X2(range_h, range_l, cum_freq[im]);
tmp = L_sub(tmp, cum);
if (tmp > 0)
{
il = im;
move16();
}
}
return il;
}
static Word16 ari_lookup_bit(Word32 cum, Word32 range, UWord16 const *cum_freq)
{
Word16 symbol = 0; /* initialize just to avoid compiler warning */
(void)cum_freq;
range = L_shl(range, 13); /* L_multi31x16_X2(range_h, range_l, 8192) */
cum = L_sub(range, cum);
if (cum > 0)
{
symbol = 1;
move16();
}
if (cum <= 0)
{
symbol = 0;
move16();
}
return symbol;
}
static Word16 ari_decode_14bits_ext(
Decoder_State_fx *st,
TastatDec *s,
UWord16 const *cum_freq,
Word16 (*lookup_fn)(Word32 cum, Word32 range, UWord16 const *cum_freq)
)
{
Word32 cum;
Word16 symbol;
Word32 low;
Word32 high;
Word32 range;
Word32 value;
Word16 i;
low = L_add(0,s->low);
high = L_add(0,s->high);
value = L_add(0,s->vobf);
range = L_sub(high, low);
cum = L_add(L_shl(L_sub(value, low), stat_bitsnew), sub(shl(1,stat_bitsnew),1));
if (cum < 0)
{
cum = L_add(0,0x7fffffff);
}
symbol = lookup_fn(cum, range, cum_freq);
high = L_add(low,mul_sbc_14bits(range,cum_freq[symbol]));
low = L_add(low,mul_sbc_14bits(range,cum_freq[symbol+1]));
FOR (i = 0; i < 0x7FFF; i++)
{
Word32 L_msb_diff, L_msb_low, L_msb_high;
L_msb_high = L_shr(L_sub(high,1),14);
L_msb_low = L_shr(low,14);
L_msb_diff = L_sub(L_msb_high, L_msb_low);
IF (L_sub(L_msb_diff,2) >= 0)
{
BREAK;
}
assert (tab_ari_qnew[L_msb_high][L_msb_low] != 0x0CCC);
assert (tab_ari_qnew[L_msb_high][L_msb_low] != 0x0BBB);
low = L_msu(low,1,tab_ari_qnew[L_msb_high][L_msb_low]);
low = L_shl(low,1);
high = L_msu(high,1,tab_ari_qnew[L_msb_high][L_msb_low]);
high = L_shl(high,1);
value = L_msu(value,1,tab_ari_qnew[L_msb_high][L_msb_low]);
value = L_mac0(L_shl(value,1),1,get_next_indice_1_fx(st));
}
s->low = low;
move32();
s->high = high;
move32();
s->vobf = value;
move32();
return symbol;
}
/**
* \brief Only for 17 symbols with new extended Tables
*/
Word16 ari_decode_14bits_s17_ext(Decoder_State_fx *st, TastatDec *s, UWord16 const *cum_freq)
{
return ari_decode_14bits_ext(st, s, cum_freq, ari_lookup_s17);
}
/**
* \brief Only for 27 symbols with new extended Tables
*/
Word16 ari_decode_14bits_s27_ext(Decoder_State_fx *st, TastatDec *s, UWord16 const *cum_freq)
{
return ari_decode_14bits_ext(st, s, cum_freq, ari_lookup_s27);
}
/**
* \brief Only for decoding one bit with uniform probability:
* the equivalent cum_freq table used is {16384, 8192, 0}
*/
Word16 ari_decode_14bits_bit_ext(Decoder_State_fx *st, TastatDec *s)
{
static const UWord16 cum_freq[3] = {16384, 8192, 0};
return ari_decode_14bits_ext(st, s, cum_freq, ari_lookup_bit);
}
static Word16 ari_lookup_pow(TastatDec *s, Word16 base)
{
Word32 cum, range;
Word16 symbol;
Word16 range_h, range_l;
Word16 pows[12]; /* "base" to the power of 2, 4, 8,... 2^12 */
Word16 lowlim, highlim, testval;
Word16 k;
range = L_sub(s->high, s->low);
cum = L_add(L_shl(L_sub(s->vobf, s->low), stat_bitsnew), sub(shl(1,stat_bitsnew),1));
range_h = extract_l(L_shr(range,15));
range_l = extract_l(L_and(range,0x7FFF));
symbol = 0;
move16();
lowlim = shr(base, 1);
highlim = 16384;
move16();
/* search for the interval where "cum" fits */
IF (L_sub(L_multi31x16_X2(range_h, range_l, lowlim), cum) > 0) /* below pow-1 */
{
pows[0] = base;
move16();
testval = base;
move16();
/* increase exponent until it is smaller than "cum" */
FOR (k = 1; k < 12; k++)
{
highlim = testval;
move16();
pows[k] = mult_r(pows[k-1], pows[k-1]);
move16();
testval = mult_r(pows[k], base);
IF (L_sub(L_multi31x16_X2(range_h, range_l, shr(testval, 1)), cum) <= 0) /* found! big range is [lowlim,testval], (now narrow it down) */
{
lowlim = testval;
move16();
k = sub(k, 1);
symbol = shl(1, k);
BREAK;
}
}
assert(k < 12); /* maximum 2^10-1*/
/* narrow the range down */
FOR (k = sub(k, 2); k >= 0; k--)
{
testval = mult_r(highlim, pows[k+1]);
IF (L_sub(L_multi31x16_X2(range_h, range_l, shr(testval, 1)), cum) <= 0)
{
lowlim = testval;
move16();
symbol = sub(symbol, shl(1, k));
}
ELSE
{
highlim = testval;
move16();
}
}
highlim = shr(highlim, 1);
lowlim = shr(lowlim, 1);
}
s->high = L_add(s->low, mul_sbc_14bits(range, highlim));
move32();
s->low = L_add(s->low, mul_sbc_14bits(range, lowlim));
move32();
return symbol;
}
static Word16 ari_lookup_sign(TastatDec *s, Word16 base)
{
Word32 cum, range;
Word16 symbol;
(void)base;
range = L_sub(s->high, s->low);
cum = L_sub(s->vobf, s->low);
range = L_shr(range, 1);
IF (L_sub(range, cum) > 0)
{
symbol = 1;
move16();
s->high = L_add(s->low, range);
move32();
}
ELSE
{
symbol = 0;
move16();
s->low = L_add(s->low, range);
move32();
}
return symbol;
}
static Word16 ari_decode_14bits_notbl(
Word16 *ptr,
Word16 bp,
Word16 bits,
Word16 *res,
TastatDec *s,
Word16 base,
Word16 (*lookup_fn)(TastatDec *s, Word16 base)
)
{
Word16 symbol;
Word32 low, high, value;
symbol = lookup_fn(s, base);
low = L_add(s->low, 0);
high = L_add(s->high, 0);
value = L_add(s->vobf, 0);
FOR (; bp<bits; ++bp)
{
Word32 L_msb_diff, L_msb_low, L_msb_high;
L_msb_high = L_shr(L_sub(high,1),14);
L_msb_low = L_shr(low,14);
L_msb_diff = L_sub(L_msb_high, L_msb_low);
IF (L_sub(L_msb_diff,2) >= 0)
{
BREAK;
}
assert (tab_ari_qnew[L_msb_high][L_msb_low] != 0x0CCC);
assert (tab_ari_qnew[L_msb_high][L_msb_low] != 0x0BBB);
low = L_msu(low,1,tab_ari_qnew[L_msb_high][L_msb_low]);
low = L_shl(low,1);
high = L_msu(high,1,tab_ari_qnew[L_msb_high][L_msb_low]);
high = L_shl(high,1);
value = L_msu(value,1,tab_ari_qnew[L_msb_high][L_msb_low]);
value = L_mac0(L_shl(value,1),1,ptr[bp]);
}
test();
test();
test();
test();
IF ((lookup_fn != ari_lookup_sign) && !(sub(bp, bits) != 0 || ! ((L_sub(s->low, low) == 0) && (L_sub(s->high, L_sub(high,1)) == 0) && (L_sub(s->vobf, value) == 0))))
{
/* This should not happen except of bit errors. */
s->high = 0;
move32();
s->low = 0;
move32();
*res = 0;
move16();
return -1;
}
s->low = low;
move32();
s->high = high;
move32();
s->vobf = value;
move32();
*res = symbol;
move16();
return bp;
}
/*------------------------------------------------------------------------
* Function: ari_decode_14bits_pow
*
* Decode a symbol which follows the exponential distribution. That is,
* symbols are in the following intervals
*
* p(x = 0) = 1 - exp(- 0.5 * base * 2)
* p(x = q>0) = exp(- (q-0.5)*base* 2) - exp(- (q+0.5)*base*2 )
*
*-------------------------------------------------------------------------*/
Word16 ari_decode_14bits_pow(Word16 *ptr, Word16 bp, Word16 bits, Word16 *res, TastatDec *s, Word16 base)
{
return ari_decode_14bits_notbl(ptr, bp, bits, res, s, base, ari_lookup_pow);
}
/*------------------------------------------------------------------------
* Function: ari_decode_14bits_sign
*
* Decode a sign with equal probabilities.
*-------------------------------------------------------------------------*/
Word16 ari_decode_14bits_sign(Word16 *ptr, Word16 bp, Word16 bits, Word16 *res, TastatDec *s)
{
return ari_decode_14bits_notbl(ptr, bp, bits, res, s, 0, ari_lookup_sign);
}