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Improved PWM sounds. Still noisy

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tudnai 2021-05-22 23:31:40 -07:00
parent 05b2da1de9
commit 1664fb4604
2 changed files with 71 additions and 74 deletions
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135
src/dev/audio/speaker.c
View File

@ -67,7 +67,7 @@ ALCcontext *ctx = NULL;
#define SPKR_MIN_VOL 0.0001 // OpenAL cannot change volume to 0.0 for some reason, so we just turn volume really low
int spkr_level = SPKR_LEVEL_ZERO;
int spkr_last_level = SPKR_LEVEL_ZERO;
#define BUFFER_COUNT 256
#define SPKR_CHANNELS 2
@ -99,6 +99,7 @@ unsigned spkr_buf_size = spkr_buf_alloc_size / sizeof(spkr_sample_t);
spkr_sample_t spkr_samples [ spkr_buf_alloc_size * DEFAULT_FPS * BUFFER_COUNT]; // can store up to 1 sec of sound
unsigned spkr_sample_idx = 0;
unsigned spkr_sample_last_idx = 0;
unsigned spkr_sample_first_pwm_idx = 0;
unsigned spkr_play_timeout = SPKR_PLAY_TIMEOUT; // increase to 32 for 240 fps, normally 8 for 30 fps
unsigned spkr_play_time = 0;
@ -353,6 +354,68 @@ void spkr_exit() {
char spkr_state = 0;
void spkr_toggle_edge ( const int level_max, const float initial_edge, const float fade_edge, const unsigned idx_diff ) {
float dumping = spkr_level - level_max;
dumping *= initial_edge;
if ( idx_diff < SPKR_SAMPLE_PWM_THRESHOLD ) {
if ( spkr_sample_first_pwm_idx == 0 ) {
spkr_sample_first_pwm_idx = spkr_sample_last_idx;
}
// printf("sd:%u\n", spkr_sample_idx_diff);
spkr_last_level = spkr_samples[spkr_sample_last_idx];
float new_level = level_max + dumping;
spkr_last_level += new_level;
spkr_last_level /= 2;
while ( spkr_sample_last_idx <= spkr_sample_idx ) {
spkr_samples[ spkr_sample_last_idx++ ] = spkr_last_level;
spkr_samples[ spkr_sample_last_idx++ ] = spkr_last_level; // stereo
}
}
else {
// if ( spkr_sample_first_pwm_idx ) {
// // calculate average speaker level
// int cnt = 1;
// int64_t avg = spkr_samples[spkr_sample_first_pwm_idx];
//
// for ( unsigned i = spkr_sample_first_pwm_idx + 2; i < spkr_sample_idx; i += 2 ) {
// cnt++;
// avg += spkr_samples[i];
// }
//
// avg /= cnt;
//
// // set average speaker level for the entire PWM region
// while ( spkr_sample_first_pwm_idx < spkr_sample_idx ) {
// spkr_samples[ spkr_sample_first_pwm_idx++ ] = avg;
// spkr_samples[ spkr_sample_first_pwm_idx++ ] = avg; // stereo
// }
//
// spkr_sample_first_pwm_idx = 0;
// }
spkr_last_level = spkr_level;
}
// save last index before we advance it...
spkr_sample_last_idx = spkr_sample_idx;
while ( fabsf(dumping) > 1 ) {
spkr_sample_t level = level_max + dumping;
spkr_samples[ spkr_sample_idx++ ] = level;
spkr_samples[ spkr_sample_idx++ ] = level; // stereo
// how smooth we want the speeker to decay, so we will hear no pops and crackles
dumping *= fade_edge;
}
spkr_level = level_max;
}
void spkr_toggle() {
// TODO: This is very slow!
@ -379,79 +442,13 @@ void spkr_toggle() {
// down edge
spkr_state = 0;
float dumping = spkr_level - SPKR_LEVEL_MIN;
dumping *= SPKR_INITIAL_TRAILING_EDGE;
if ( spkr_sample_idx_diff < SPKR_SAMPLE_PWM_THRESHOLD ) {
// printf("sd:%u\n", spkr_sample_idx_diff);
spkr_sample_t last_level = spkr_samples[spkr_sample_last_idx];
float new_level = SPKR_LEVEL_MIN + dumping;
last_level += new_level;
last_level /= 2;
float dumping = last_level - SPKR_LEVEL_MIN;
dumping *= SPKR_INITIAL_TRAILING_EDGE;
while ( spkr_sample_last_idx < spkr_sample_idx ) {
spkr_samples[ spkr_sample_last_idx++ ] = last_level;
spkr_samples[ spkr_sample_last_idx++ ] = last_level; // stereo
}
}
// save last index before we advance it...
spkr_sample_last_idx = spkr_sample_idx;
while ( dumping > 1 ) {
spkr_sample_t level = SPKR_LEVEL_MIN + dumping;
spkr_samples[ spkr_sample_idx++ ] = level;
spkr_samples[ spkr_sample_idx++ ] = level; // stereo
// how smooth we want the speeker to decay, so we will hear no pops and crackles
// 0.9 gives you a kind of saw wave at 1KHz (beep)
// 0.7 is better, but Xonix gives you a bit distorted speech and Donkey Kong does not sound the same
dumping *= SPKR_FADE_TRAILING_EDGE;
}
spkr_level = SPKR_LEVEL_MIN;
spkr_toggle_edge(SPKR_LEVEL_MIN, SPKR_INITIAL_TRAILING_EDGE, SPKR_FADE_TRAILING_EDGE, spkr_sample_idx_diff);
}
else {
// up edge
spkr_state = 1;
float dumping = spkr_level - SPKR_LEVEL_MAX;
dumping *= SPKR_INITIAL_LEADING_EDGE;
if ( spkr_sample_idx_diff < SPKR_SAMPLE_PWM_THRESHOLD ) {
// printf("sd:%u\n", spkr_sample_idx_diff);
spkr_sample_t last_level = spkr_samples[spkr_sample_last_idx];
float new_level = SPKR_LEVEL_MAX + dumping;
last_level += new_level;
last_level /= 2;
float dumping = last_level - SPKR_LEVEL_MIN;
dumping *= SPKR_INITIAL_TRAILING_EDGE;
while ( spkr_sample_last_idx < spkr_sample_idx + SPKR_SAMPLE_PWM_THRESHOLD ) {
spkr_samples[ spkr_sample_last_idx++ ] = last_level;
spkr_samples[ spkr_sample_last_idx++ ] = last_level; // stereo
}
}
// save last index before we advance it...
spkr_sample_last_idx = spkr_sample_idx;
while ( dumping < -1 ) {
spkr_sample_t level = SPKR_LEVEL_MAX + dumping;
spkr_samples[ spkr_sample_idx++ ] = level;
spkr_samples[ spkr_sample_idx++ ] = level; // stereo
// how smooth we want the speeker to decay, so we will hear no pops and crackles
// 0.9 gives you a kind of saw wave at 1KHz (beep)
// 0.7 is better, but Xonix gives you a bit distorted speech and Donkey Kong does not sound the same
dumping *= SPKR_FADE_LEADING_EDGE;
}
spkr_level = SPKR_LEVEL_MAX;
spkr_toggle_edge(SPKR_LEVEL_MAX, SPKR_INITIAL_LEADING_EDGE, SPKR_FADE_LEADING_EDGE, spkr_sample_idx_diff);
}

10
src/dev/audio/speaker.h
View File

@ -50,12 +50,12 @@
//#define SPKR_LEVEL_MAX (+1000)
#define SPKR_FADE_LEADING_EDGE 0.32
#define SPKR_FADE_TRAILING_EDGE 0.16
#define SPKR_INITIAL_LEADING_EDGE 0.96 // leading edge should be pretty steep to get sharp sound plus to avoid Wavy Navy high pitch sound
#define SPKR_INITIAL_TRAILING_EDGE 0.72 // need a bit of slope to get Xonix sound good
#define SPKR_FADE_LEADING_EDGE 0.64
#define SPKR_FADE_TRAILING_EDGE 0.24
#define SPKR_INITIAL_LEADING_EDGE 1.00 // leading edge should be pretty steep to get sharp sound plus to avoid Wavy Navy high pitch sound
#define SPKR_INITIAL_TRAILING_EDGE 0.88 // need a bit of slope to get Xonix sound good
#define SPKR_SAMPLE_PWM_THRESHOLD 10 // to detect PWM controlled speaker control like in Wavy Navy or Xonix
#define SPKR_SAMPLE_PWM_THRESHOLD 12 // to detect PWM controlled speaker control like in Wavy Navy or Xonix