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coding: separate gsm0503_tch_a[fh]s_decode_inband() 

These functions can be re-used for parsing in-band data from DTX
specific frames like SID_FIRST, SID_UPDATE, SID_ONSET, etc.

Change-Id: I0106de7a7f87517006e323299b2dc08457d1c6cf
Related: OS#5570
This commit is contained in:
Vadim Yanitskiy 2022-05-24 02:51:50 +07:00 committed by fixeria
parent cc4213e927
commit b57e6392fb
1 changed files with 46 additions and 26 deletions
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72
src/coding/gsm0503_coding.c
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@ -2115,6 +2115,26 @@ int gsm0503_tch_hr_encode(ubit_t *bursts, const uint8_t *tch_data, int len)
return 0;
}
/* TCH/AFS: parse codec ID (CMI or CMC/CMR) from coded in-band data (16 bit) */
static uint8_t gsm0503_tch_afs_decode_inband(const sbit_t *cB)
{
unsigned int id = 0, best = 0;
unsigned int i, j, k;
for (i = 0; i < 4; i++) {
/* FIXME: why not using remaining (16 - 8) soft-bits here? */
for (j = 0, k = 0; j < 8; j++)
k += abs(((int)gsm0503_afs_ic_sbit[i][j]) - ((int)cB[j]));
if (i == 0 || k < best) {
best = k;
id = i;
}
}
return id;
}
/*! Perform channel decoding of a TCH/AFS channel according TS 05.03
* \param[out] tch_data Codec frame in RTP payload format
* \param[in] bursts buffer containing the symbols of 8 bursts
@ -2157,7 +2177,7 @@ int gsm0503_tch_afs_decode_dtx(uint8_t *tch_data, const sbit_t *bursts,
{
sbit_t iB[912], cB[456], h;
ubit_t d[244], p[6], conv[250];
int i, j, k, best = 0, rv, len, steal = 0, id = -1;
int i, rv, len, steal = 0, id = -1;
*n_errors = 0; *n_bits_total = 0;
static ubit_t sid_first_dummy[64] = { 0 };
sbit_t sid_update_enc[256];
@ -2236,18 +2256,8 @@ int gsm0503_tch_afs_decode_dtx(uint8_t *tch_data, const sbit_t *bursts,
}
}
for (i = 0; i < 4; i++) {
for (j = 0, k = 0; j < 8; j++)
k += abs(((int)gsm0503_afs_ic_sbit[i][j]) - ((int)cB[j]));
if (i == 0 || k < best) {
best = k;
id = i;
}
}
/* Check if indicated codec fits into range of codecs */
if (id >= codecs) {
/* Parse codec ID (CMI or CMC/CMR) and check if it fits into range of codecs */
if ((id = gsm0503_tch_afs_decode_inband(&cB[0])) >= codecs) {
/* Codec mode out of range, return id */
return id;
}
@ -2578,6 +2588,26 @@ invalid_length:
return -1;
}
/* TCH/AHS: parse codec ID (CMI or CMC/CMR) from coded in-band data (16 bit) */
static uint8_t gsm0503_tch_ahs_decode_inband(const sbit_t *cB)
{
unsigned int id = 0, best = 0;
unsigned int i, j, k;
for (i = 0, k = 0; i < 4; i++) {
/* FIXME: why not using remaining (16 - 4) soft-bits here? */
for (j = 0, k = 0; j < 4; j++)
k += abs(((int)gsm0503_ahs_ic_sbit[i][j]) - ((int)cB[j]));
if (i == 0 || k < best) {
best = k;
id = i;
}
}
return id;
}
/*! Perform channel decoding of a TCH/AFS channel according TS 05.03
* \param[out] tch_data Codec frame in RTP payload format
* \param[in] bursts buffer containing the symbols of 8 bursts
@ -2622,7 +2652,7 @@ int gsm0503_tch_ahs_decode_dtx(uint8_t *tch_data, const sbit_t *bursts, int odd,
{
sbit_t iB[912], cB[456], h;
ubit_t d[244], p[6], conv[135];
int i, j, k, best = 0, rv, len, steal = 0, id = -1;
int i, rv, len, steal = 0, id = -1;
static ubit_t sid_first_dummy[64] = { 0 };
/* only unmap the stealing bits */
@ -2738,18 +2768,8 @@ int gsm0503_tch_ahs_decode_dtx(uint8_t *tch_data, const sbit_t *bursts, int odd,
}
}
for (i = 0; i < 4; i++) {
for (j = 0, k = 0; j < 4; j++)
k += abs(((int)gsm0503_ahs_ic_sbit[i][j]) - ((int)cB[j]));
if (i == 0 || k < best) {
best = k;
id = i;
}
}
/* Check if indicated codec fits into range of codecs */
if (id >= codecs) {
/* Parse codec ID (CMI or CMC/CMR) and check if it fits into range of codecs */
if ((id = gsm0503_tch_ahs_decode_inband(&cB[0])) >= codecs) {
/* Codec mode out of range, return id */
return id;
}