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authorAndreas Eversberg <jolly@eversberg.eu>2018-10-14 13:07:25 +0200
committerAndreas Eversberg <jolly@eversberg.eu>2018-10-14 13:07:25 +0200
commite9a7f610eefbc886518cd88284eeecb1ebf8f10c (patch)
treeea2d368200a91c7b6fe16856da9b041bfc94288e
parent56d8df5351a53fb78c74489415fcbf1c62fc6a7e (diff)
Compandor: Remove unused option for unaffected level
-rw-r--r--src/amps/dsp.c3
-rw-r--r--src/cnetz/dsp.c3
-rw-r--r--src/libcompandor/compandor.c26
-rw-r--r--src/libcompandor/compandor.h4
-rw-r--r--src/nmt/dsp.c3
-rw-r--r--src/r2000/dsp.c3
-rw-r--r--src/test/test_compandor.c2
7 files changed, 14 insertions, 30 deletions
diff --git a/src/amps/dsp.c b/src/amps/dsp.c
index 8f4c84a..1bf8c43 100644
--- a/src/amps/dsp.c
+++ b/src/amps/dsp.c
@@ -99,7 +99,6 @@
#define PI M_PI
-#define COMPANDOR_0DB 1.0 /* A level of 0dBm (1.0) shall be unaccected */
#define AMPS_MAX_DEVIATION 8000.0
#define AMPS_MAX_MODULATION 10000.0
#define AMPS_DBM0_DEVIATION 2900.0 /* deviation of dBm0 at 1 kHz */
@@ -195,7 +194,7 @@ int dsp_init_sender(amps_t *amps, int tolerant)
int half;
/* attack (3ms) and recovery time (13.5ms) according to amps specs */
- init_compandor(&amps->cstate, 8000, 3.0, 13.5, COMPANDOR_0DB);
+ init_compandor(&amps->cstate, 8000, 3.0, 13.5);
PDEBUG_CHAN(DDSP, DEBUG_DEBUG, "Init DSP for transceiver.\n");
diff --git a/src/cnetz/dsp.c b/src/cnetz/dsp.c
index 38e5f30..f05c883 100644
--- a/src/cnetz/dsp.c
+++ b/src/cnetz/dsp.c
@@ -43,7 +43,6 @@
#define MAX_DEVIATION 4000.0
#define MAX_MODULATION 3000.0
#define DBM0_DEVIATION 4000.0 /* deviation of dBm0 at 1 kHz */
-#define COMPANDOR_0DB 1.0 /* A level of 0dBm (1.0) shall be unaccected */
#define FSK_DEVIATION (2500.0 / DBM0_DEVIATION) /* no emphasis */
#define MAX_DISPLAY 1.4 /* something above dBm0, no emphasis */
#define BITRATE 5280.0 /* bits per second */
@@ -151,7 +150,7 @@ int dsp_init_sender(cnetz_t *cnetz, int measure_speed, double clock_speed[2], en
/* init compandor, according to C-Netz specs, attack and recovery time
* shall not exceed according to ITU G.162 */
- init_compandor(&cnetz->cstate, 8000, 5.0, 22.5, COMPANDOR_0DB);
+ init_compandor(&cnetz->cstate, 8000, 5.0, 22.5);
/* use this filter to compensate level changes between two subsequent audio chunks */
RC = 1.0 / (CUT_OFF_OFFSET * 2.0 *3.14);
diff --git a/src/libcompandor/compandor.c b/src/libcompandor/compandor.c
index 3a2ca9b..b06602e 100644
--- a/src/libcompandor/compandor.c
+++ b/src/libcompandor/compandor.c
@@ -32,7 +32,7 @@
#define EXPAND_ATTACK_FACTOR 1.145 /* about 0.57 after 6 dB step up */
#define EXPAND_RECOVERY_FACTOR 0.753 /* about 1.51 after 6 dB step down */
-/* Minimum level value to keep state */
+/* Minimum level value to keep state (-60 dB) */
#define ENVELOPE_MIN 0.001
/* Maximum level, to prevent sqrt_tab to overflow */
@@ -46,7 +46,7 @@ static double sqrt_tab[10000];
* Hopefully this is correct
*
*/
-void init_compandor(compandor_t *state, double samplerate, double attack_ms, double recovery_ms, double unaffected_level)
+void init_compandor(compandor_t *state, double samplerate, double attack_ms, double recovery_ms)
{
int i;
@@ -60,8 +60,6 @@ void init_compandor(compandor_t *state, double samplerate, double attack_ms, dou
state->c.step_down = pow(COMPRESS_RECOVERY_FACTOR, 1000.0 / recovery_ms / samplerate);
state->e.step_up = pow(EXPAND_ATTACK_FACTOR, 1000.0 / attack_ms / samplerate);
state->e.step_down = pow(EXPAND_RECOVERY_FACTOR, 1000.0 / recovery_ms / samplerate);
- state->c.unaffected = unaffected_level;
- state->e.unaffected = unaffected_level;
// FIXME: make global, not at instance
for (i = 0; i < 10000; i++)
@@ -70,19 +68,17 @@ void init_compandor(compandor_t *state, double samplerate, double attack_ms, dou
void compress_audio(compandor_t *state, sample_t *samples, int num)
{
- double value, peak, envelope, step_up, step_down, unaffected;
+ double value, peak, envelope, step_up, step_down;
int i;
step_up = state->c.step_up;
step_down = state->c.step_down;
peak = state->c.peak;
envelope = state->c.envelope;
- unaffected = state->c.unaffected;
// printf("envelope=%.4f\n", envelope);
for (i = 0; i < num; i++) {
- /* normalize sample value to unaffected level */
- value = *samples / unaffected;
+ value = *samples;
/* 'peak' is the level that raises directly with the signal
* level, but falls with specified recovery rate. */
@@ -101,11 +97,9 @@ void compress_audio(compandor_t *state, sample_t *samples, int num)
if (envelope > ENVELOPE_MAX)
envelope = ENVELOPE_MAX;
- value = value / sqrt_tab[(int)(envelope / 0.001)];
+ *samples++ = value / sqrt_tab[(int)(envelope / 0.001)];
//if (i > 47000.0 && i < 48144)
//printf("time=%.4f envelope=%.4fdb, value=%.4f\n", (double)i/48000.0, 20*log10(envelope), value);
-
- *samples++ = value * unaffected;
}
//exit(0);
@@ -115,18 +109,16 @@ void compress_audio(compandor_t *state, sample_t *samples, int num)
void expand_audio(compandor_t *state, sample_t *samples, int num)
{
- double value, peak, envelope, step_up, step_down, unaffected;
+ double value, peak, envelope, step_up, step_down;
int i;
step_up = state->e.step_up;
step_down = state->e.step_down;
peak = state->e.peak;
envelope = state->e.envelope;
- unaffected = state->e.unaffected;
for (i = 0; i < num; i++) {
- /* normalize sample value to 0 DB level */
- value = *samples / unaffected;
+ value = *samples;
/* for comments: see compress_audio() */
if (fabs(value) > peak)
@@ -140,9 +132,7 @@ void expand_audio(compandor_t *state, sample_t *samples, int num)
if (envelope < ENVELOPE_MIN)
envelope = ENVELOPE_MIN;
- value = value * envelope;
-
- *samples++ = value * unaffected;
+ *samples++ = value * envelope;
}
state->e.envelope = envelope;
diff --git a/src/libcompandor/compandor.h b/src/libcompandor/compandor.h
index 25d51ea..e912609 100644
--- a/src/libcompandor/compandor.h
+++ b/src/libcompandor/compandor.h
@@ -1,14 +1,12 @@
typedef struct compandor {
struct {
- double unaffected;
double step_up;
double step_down;
double peak;
double envelope;
} c;
struct {
- double unaffected;
double step_up;
double step_down;
double peak;
@@ -16,7 +14,7 @@ typedef struct compandor {
} e;
} compandor_t;
-void init_compandor(compandor_t *state, double samplerate, double attack_ms, double recovery_ms, double unaffected_level);
+void init_compandor(compandor_t *state, double samplerate, double attack_ms, double recovery_ms);
void compress_audio(compandor_t *state, sample_t *samples, int num);
void expand_audio(compandor_t *state, sample_t *samples, int num);
diff --git a/src/nmt/dsp.c b/src/nmt/dsp.c
index 1a9c49f..e9e2253 100644
--- a/src/nmt/dsp.c
+++ b/src/nmt/dsp.c
@@ -55,7 +55,6 @@
#define MAX_DEVIATION 4700.0
#define MAX_MODULATION 4055.0
#define DBM0_DEVIATION 3000.0 /* deviation of dBm0 at 1 kHz */
-#define COMPANDOR_0DB 1.0 /* A level of 0dBm (1.0) shall be unaccected */
#define TX_PEAK_FSK (4200.0 / 1800.0 * 1000.0 / DBM0_DEVIATION)
#define TX_PEAK_SUPER (300.0 / 4015.0 * 1000.0 / DBM0_DEVIATION)
#define BIT_RATE 1200.0
@@ -110,7 +109,7 @@ int dsp_init_sender(nmt_t *nmt, double deviation_factor)
int i;
/* attack (3ms) and recovery time (13.5ms) according to NMT specs */
- init_compandor(&nmt->cstate, 8000, 3.0, 13.5, COMPANDOR_0DB);
+ init_compandor(&nmt->cstate, 8000, 3.0, 13.5);
PDEBUG_CHAN(DDSP, DEBUG_DEBUG, "Init DSP for Transceiver.\n");
diff --git a/src/r2000/dsp.c b/src/r2000/dsp.c
index 22634aa..fd438e4 100644
--- a/src/r2000/dsp.c
+++ b/src/r2000/dsp.c
@@ -48,7 +48,6 @@
#define MAX_DEVIATION 2500.0
#define MAX_MODULATION 2550.0
#define DBM0_DEVIATION 1500.0 /* deviation of dBm0 at 1 kHz */
-#define COMPANDOR_0DB 1.0 /* A level of 0dBm (1.0) shall be unaccected */
#define TX_PEAK_FSK (1425.0 / 1500.0 * 1000.0 / DBM0_DEVIATION) /* with emphasis */
#define TX_PEAK_SUPER (300.0 / DBM0_DEVIATION) /* no emphasis */
#define FSK_BIT_RATE 1200.0
@@ -76,7 +75,7 @@ static void super_receive_bit(void *inst, int bit, double quality, double level)
int dsp_init_sender(r2000_t *r2000)
{
/* attack (3ms) and recovery time (13.5ms) according to NMT specs */
- init_compandor(&r2000->cstate, 8000, 3.0, 13.5, COMPANDOR_0DB);
+ init_compandor(&r2000->cstate, 8000, 3.0, 13.5);
PDEBUG_CHAN(DDSP, DEBUG_DEBUG, "Init DSP for Transceiver.\n");
diff --git a/src/test/test_compandor.c b/src/test/test_compandor.c
index 4f916a8..b1cd51e 100644
--- a/src/test/test_compandor.c
+++ b/src/test/test_compandor.c
@@ -72,7 +72,7 @@ int main(void)
sample_t samples[SAMPLERATE * 2];
int f;
- init_compandor(&cstate, SAMPLERATE, ATTACK_MS, RECOVERY_MS, 1.0);
+ init_compandor(&cstate, SAMPLERATE, ATTACK_MS, RECOVERY_MS);
for (f = 0; f < 3; f++) {
/* -16 and -4 dB */