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ADPCM and G.726 performance improvements courtesy fOSSiL (bug #2843)

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@4249 65c4cc65-6c06-0410-ace0-fbb531ad65f3
This commit is contained in:
Mark Spencer
2004-11-15 00:56:53 +00:00
parent 9bf48f9ce7
commit 8de7794637
2 changed files with 353 additions and 229 deletions
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227
codecs/codec_adpcm.c
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@@ -25,6 +25,9 @@
#include <string.h>
#include <unistd.h>
/* define NOT_BLI to use a faster but not bit-level identical version */
/* #define NOT_BLI */
#define BUFFER_SIZE 8096 /* size for the translation buffers */
AST_MUTEX_DEFINE_STATIC(localuser_lock);
@@ -41,28 +44,28 @@ static char *tdesc = "Adaptive Differential PCM Coder/Decoder";
* Step size index shift table
*/
static short indsft[8] = { -1, -1, -1, -1, 2, 4, 6, 8 };
static int indsft[8] = { -1, -1, -1, -1, 2, 4, 6, 8 };
/*
* Step size table, where stpsz[i]=floor[16*(11/10)^i]
*/
static short stpsz[49] = {
static int stpsz[49] = {
16, 17, 19, 21, 23, 25, 28, 31, 34, 37, 41, 45, 50, 55, 60, 66, 73,
80, 88, 97, 107, 118, 130, 143, 157, 173, 190, 209, 230, 253, 279,
307, 337, 371, 408, 449, 494, 544, 598, 658, 724, 796, 876, 963,
1060, 1166, 1282, 1411, 1552
};
/*
* Nibble to bit map
/*
* Decoder/Encoder state
* States for both encoder and decoder are synchronized
*/
static short nbl2bit[16][4] = {
{1, 0, 0, 0}, {1, 0, 0, 1}, {1, 0, 1, 0}, {1, 0, 1, 1},
{1, 1, 0, 0}, {1, 1, 0, 1}, {1, 1, 1, 0}, {1, 1, 1, 1},
{-1, 0, 0, 0}, {-1, 0, 0, 1}, {-1, 0, 1, 0}, {-1, 0, 1, 1},
{-1, 1, 0, 0}, {-1, 1, 0, 1}, {-1, 1, 1, 0}, {-1, 1, 1, 1}
struct adpcm_state {
int ssindex;
int signal;
int zero_count;
int next_flag;
};
/*
@@ -76,51 +79,64 @@ static short nbl2bit[16][4] = {
* Sets the index to the step size table for the next encode.
*/
static inline void
decode (unsigned char encoded, short *ssindex, short *signal, unsigned char *rkey, unsigned char *next)
static inline short
decode(int encoded, struct adpcm_state* state)
{
short diff, step;
step = stpsz[*ssindex];
int diff;
int step;
int sign;
diff = step * nbl2bit[encoded][1] +
(step >> 1) * nbl2bit[encoded][2] +
(step >> 2) * nbl2bit[encoded][3] +
(step >> 3);
if (nbl2bit[encoded][2] && (step & 0x1))
diff++;
diff *= nbl2bit[encoded][0];
step = stpsz[state->ssindex];
if ( *next & 0x1 )
*signal -= 8;
else if ( *next & 0x2 )
*signal += 8;
sign = encoded & 0x08;
encoded &= 0x07;
#ifdef NOT_BLI
diff = (((encoded << 1) + 1) * step) >> 3;
#else /* BLI code */
diff = step >> 3;
if (encoded & 4) diff += step;
if (encoded & 2) diff += step >> 1;
if (encoded & 1) diff += step >> 2;
if ((encoded >> 1) & step & 0x1)
diff++;
#endif
if (sign)
diff = -diff;
*signal += diff;
if (state->next_flag & 0x1)
state->signal -= 8;
else if (state->next_flag & 0x2)
state->signal += 8;
if (*signal > 2047)
*signal = 2047;
else if (*signal < -2047)
*signal = -2047;
state->signal += diff;
*next = 0;
if (state->signal > 2047)
state->signal = 2047;
else if (state->signal < -2047)
state->signal = -2047;
state->next_flag = 0;
#ifdef AUTO_RETURN
if( encoded & 0x7 )
*rkey = 0;
else if ( ++(*rkey) == 24 ) {
*rkey = 0;
if (*signal > 0)
*next = 0x1;
else if (*signal < 0)
*next = 0x2;
}
if (encoded)
state->zero_count = 0;
else if (++(state->zero_count) == 24)
{
state->zero_count = 0;
if (state->signal > 0)
state->next_flag = 0x1;
else if (state->signal < 0)
state->next_flag = 0x2;
}
#endif
*ssindex = *ssindex + indsft[(encoded & 7)];
if (*ssindex < 0)
*ssindex = 0;
else if (*ssindex > 48)
*ssindex = 48;
state->ssindex += indsft[encoded];
if (state->ssindex < 0)
state->ssindex = 0;
else if (state->ssindex > 48)
state->ssindex = 48;
return state->signal << 4;
}
/*
@@ -135,44 +151,63 @@ decode (unsigned char encoded, short *ssindex, short *signal, unsigned char *rke
* signal gets updated with each pass.
*/
static inline unsigned char
adpcm (short csig, short *ssindex, short *signal, unsigned char *rkey, unsigned char *next)
static inline int
adpcm(short csig, struct adpcm_state* state)
{
short diff, step;
unsigned char encoded;
step = stpsz[*ssindex];
/*
* Clip csig if too large or too small
*/
csig >>= 4;
int diff;
int step;
int encoded;
diff = csig - *signal;
if (diff < 0)
{
encoded = 8;
diff = -diff;
}
else
encoded = 0;
if (diff >= step)
{
encoded |= 4;
diff -= step;
}
step >>= 1;
if (diff >= step)
{
encoded |= 2;
diff -= step;
}
step >>= 1;
if (diff >= step)
encoded |= 1;
decode (encoded, ssindex, signal, rkey, next);
return (encoded);
/*
* Clip csig if too large or too small
*/
csig >>= 4;
step = stpsz[state->ssindex];
diff = csig - state->signal;
#ifdef NOT_BLI
if (diff < 0)
{
encoded = (-diff << 2) / step;
if (encoded > 7)
encoded = 7;
encoded |= 0x08;
}
else
{
encoded = (diff << 2) / step;
if (encoded > 7)
encoded = 7;
}
#else /* BLI code */
if (diff < 0)
{
encoded = 8;
diff = -diff;
}
else
encoded = 0;
if (diff >= step)
{
encoded |= 4;
diff -= step;
}
step >>= 1;
if (diff >= step)
{
encoded |= 2;
diff -= step;
}
step >>= 1;
if (diff >= step)
encoded |= 1;
#endif /* NOT_BLI */
/* feedback to state */
decode(encoded, state);
return encoded;
}
/*
@@ -185,10 +220,7 @@ struct adpcm_encoder_pvt
char offset[AST_FRIENDLY_OFFSET]; /* Space to build offset */
short inbuf[BUFFER_SIZE]; /* Unencoded signed linear values */
unsigned char outbuf[BUFFER_SIZE]; /* Encoded ADPCM, two nibbles to a word */
short ssindex;
short signal;
unsigned char zero_count;
unsigned char next_flag;
struct adpcm_state state;
int tail;
};
@@ -201,10 +233,7 @@ struct adpcm_decoder_pvt
struct ast_frame f;
char offset[AST_FRIENDLY_OFFSET]; /* Space to build offset */
short outbuf[BUFFER_SIZE]; /* Decoded signed linear values */
short ssindex;
short signal;
unsigned char zero_count;
unsigned char next_flag;
struct adpcm_state state;
int tail;
};
@@ -287,11 +316,8 @@ adpcmtolin_framein (struct ast_translator_pvt *pvt, struct ast_frame *f)
b = f->data;
for (x=0;x<f->datalen;x++) {
decode((b[x] >> 4) & 0xf, &tmp->ssindex, &tmp->signal, &tmp->zero_count, &tmp->next_flag);
tmp->outbuf[tmp->tail++] = tmp->signal << 4;
decode(b[x] & 0x0f, &tmp->ssindex, &tmp->signal, &tmp->zero_count, &tmp->next_flag);
tmp->outbuf[tmp->tail++] = tmp->signal << 4;
tmp->outbuf[tmp->tail++] = decode((b[x] >> 4) & 0xf, &tmp->state);
tmp->outbuf[tmp->tail++] = decode(b[x] & 0x0f, &tmp->state);
}
return 0;
@@ -374,26 +400,25 @@ static struct ast_frame *
lintoadpcm_frameout (struct ast_translator_pvt *pvt)
{
struct adpcm_encoder_pvt *tmp = (struct adpcm_encoder_pvt *) pvt;
unsigned char adpcm0, adpcm1;
int i_max, i;
if (tmp->tail < 2) return NULL;
i_max = (tmp->tail / 2) * 2;
i_max = tmp->tail & ~1; /* atomic size is 2 samples */
/* What is this, state debugging? should be #ifdef'd then
tmp->outbuf[0] = tmp->ssindex & 0xff;
tmp->outbuf[1] = (tmp->signal >> 8) & 0xff;
tmp->outbuf[2] = (tmp->signal & 0xff);
tmp->outbuf[3] = tmp->zero_count;
tmp->outbuf[4] = tmp->next_flag;
*/
for (i = 0; i < i_max; i+=2)
{
adpcm0 = adpcm (tmp->inbuf[i], &tmp->ssindex, &tmp->signal, &tmp->zero_count, &tmp->next_flag);
adpcm1 = adpcm (tmp->inbuf[i+1], &tmp->ssindex, &tmp->signal, &tmp->zero_count, &tmp->next_flag);
tmp->outbuf[i/2] = (adpcm0 << 4) | adpcm1;
tmp->outbuf[i/2] =
(adpcm(tmp->inbuf[i ], &tmp->state) << 4) |
(adpcm(tmp->inbuf[i+1], &tmp->state) );
};