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Rename dbm0 (level) to speech (level)

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In mobile communications we use speech level instead of milliwatts.
The deviation (FM) is always based on speech level, not on 1 milliwatt.
This commit is contained in:
Andreas Eversberg
2019-12-05 08:33:08 +01:00
parent c3da4a77d4
commit c2f14834e5
16 changed files with 105 additions and 104 deletions
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22
src/libsendevolumenregler/sendevolumenregler.c
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@@ -38,22 +38,22 @@
/*
* Init function
*
* abwaerts_dbs = how many dB per second to lower the amplification, if input signal is above dBm0
* aufwaerts_dbs = how many dB per second to raise the amplification, if input signal is below dBm0
* maximum_db = limit of the output level above dBm0
* abwaerts_dbs = how many dB per second to lower the amplification, if input signal is above db0
* aufwaerts_dbs = how many dB per second to raise the amplification, if input signal is below db0
* maximum_db = limit of the output level above db0
* minimum_db = below this input level, the amplification is not raised, so it stays constant.
* dbm0_level = target level to be treated as 0 dB
* db0_level = target level to be treated as 0 dB
*
* Hopefully this is correct
*
*/
void init_sendevolumenregler(sendevolumenregler_t *state, double samplerate, double abwaerts_dbs, double aufwaerts_dbs, double maximum_db, double minimum_db, double dbm0_level)
void init_sendevolumenregler(sendevolumenregler_t *state, double samplerate, double abwaerts_dbs, double aufwaerts_dbs, double maximum_db, double minimum_db, double db0_level)
{
memset(state, 0, sizeof(*state));
state->peak = 1.0;
state->envelope = 1.0;
state->dbm0_level = dbm0_level;
state->db0_level = db0_level;
state->step_down = pow(db2level(abwaerts_dbs), 1.0 / samplerate);
state->step_up = pow(db2level(aufwaerts_dbs), 1.0 / samplerate);
state->maximum_level = db2level(maximum_db);
@@ -72,10 +72,10 @@ void init_sendevolumenregler(sendevolumenregler_t *state, double samplerate, dou
*/
void sendevolumenregler(sendevolumenregler_t *state, sample_t *samples, int num)
{
double value, peak, envelope, step_up, step_down, maximum_level, minimum_level, dbm0_level;
double value, peak, envelope, step_up, step_down, maximum_level, minimum_level, db0_level;
int i;
dbm0_level = state->dbm0_level;
db0_level = state->db0_level;
step_up = state->step_up;
step_down = state->step_down;
maximum_level = state->maximum_level;
@@ -84,8 +84,8 @@ void sendevolumenregler(sendevolumenregler_t *state, sample_t *samples, int num)
envelope = state->envelope;
for (i = 0; i < num; i++) {
/* normalize sample value to dbm0_level level */
value = *samples / dbm0_level;
/* normalize sample value to db0_level level */
value = *samples / db0_level;
/* 'peak' is the level that raises directly with the value
* level, but falls as specified by step_up. */
@@ -106,7 +106,7 @@ void sendevolumenregler(sendevolumenregler_t *state, sample_t *samples, int num)
if (peak / envelope > maximum_level)
envelope = peak / maximum_level;
*samples++ = value / envelope * dbm0_level;
*samples++ = value / envelope * db0_level;
}
state->envelope = envelope;

4
src/libsendevolumenregler/sendevolumenregler.h
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@@ -6,9 +6,9 @@ typedef struct sendevolumenregler {
double step_down;
double minimum_level;
double maximum_level;
double dbm0_level;
double db0_level;
} sendevolumenregler_t;
void init_sendevolumenregler(sendevolumenregler_t *state, double samplerate, double abwaerts_dbs, double aufwaerts_dbs, double maximum_db, double minimum_db, double dbm0_level);
void init_sendevolumenregler(sendevolumenregler_t *state, double samplerate, double abwaerts_dbs, double aufwaerts_dbs, double maximum_db, double minimum_db, double db0_level);
void sendevolumenregler(sendevolumenregler_t *state, sample_t *samples, int num);