static void bf_est_update(short fill) {
// the rate-matching system needs to decide how full to keep the buffer.
// the initial fill is present when the system starts to output samples,
// but most output chains will instantly gobble their own buffer's worth of
// data. we average for a while to decide where to draw the line.
if (fill_count < 1000) {
desired_fill += (double)fill/1000.0;
fill_count++;
return;
} else if (fill_count == 1000) {
// this information could be used to help estimate our effective latency?
desired_fill = (2*config.buffer_start_fill) - desired_fill;
debug(1, "established desired fill of %f frames, "
"so output chain buffered about %f frames\n", desired_fill,
desired_fill - config.buffer_start_fill);
fill_count++;
}
#define CONTROL_A (1e-4)
#define CONTROL_B (1e-1)
double buf_delta = fill - desired_fill;
bf_est_err = biquad_filt(&bf_err_lpf, buf_delta);
double err_deriv = biquad_filt(&bf_err_deriv_lpf, bf_est_err - bf_last_err);
double adj_error = CONTROL_A * bf_est_err;
bf_est_drift = biquad_filt(&bf_drift_lpf, CONTROL_B*(adj_error + err_deriv) + bf_est_drift);
debug(3, "bf %d err %f drift %f desiring %f ed %f estd %f\n",
fill, bf_est_err, bf_est_drift, desired_fill, err_deriv, err_deriv + adj_error);
bf_playback_rate = 1.0 + adj_error + bf_est_drift;
bf_last_err = bf_est_err;
}
static inline void bf_est_update(short fill) {
if (fill_count < 1000) {
desired_fill += (double)fill/1000.0;
fill_count++;
return;
}
#define CONTROL_A (1e-4)
#define CONTROL_B (1e-1)
double buf_delta = fill - desired_fill;
bf_est_err = biquad_filt(&bf_err_lpf, buf_delta);
double err_deriv = biquad_filt(&bf_err_deriv_lpf, bf_est_err - bf_last_err);
double adj_error = CONTROL_A * bf_est_err;
bf_est_drift = biquad_filt(&bf_drift_lpf, CONTROL_B*(adj_error + err_deriv) + bf_est_drift);
#ifdef DEBUG
fprintf(stderr, "bf %d err %f drift %f desiring %f ed %f estd %f\n",
fill, bf_est_err, bf_est_drift, desired_fill, err_deriv, err_deriv + adj_error);
#endif
bf_playback_rate = 1.0 + adj_error + bf_est_drift;
bf_last_err = bf_est_err;
}
void display(void) {
if (rptr==wptr) {
glutSwapBuffers();
glutPostRedisplay();
return;
}
glDrawBuffer(GL_BACK);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
int n;
double x, y;
glBegin(GL_LINES);
glColor4f(0,1,0,0.7);
glVertex2f(last_x, last_y);
n = 0;
again:
while (rptr != wptr) {
x = biquad_filt(&lpf_x, ringbuf[rptr*4] / 32768.0);
y = biquad_filt(&lpf_y, ringbuf[rptr*4+1] / 32768.0);
if (!fullbright)
glColor4f(0, ringbuf[rptr*4+2]/32768.0, 0,0.7);
rptr++;
if (rptr>=RING_SIZE) {
rptr = 0;
fprintf(stderr, "r");
}
glVertex2f(x, y);
glVertex2f(x, y);
n++;
}
if (n < 1000) {
glutSwapBuffers();
goto again;
}
glVertex2f(x, y);
last_x = x; last_y = y;
glEnd();
#define SKIP_ACCUM // accumulation buffer gives nice smooth decay effect, but is slow as tar on most machines
#ifndef SKIP_ACCUM
glAccum(GL_MULT, 0.7);
glAccum(GL_ACCUM, 1.0);
glDrawBuffer(GL_FRONT);
glAccum(GL_RETURN, 1.0);
glFlush();
#else
//glDrawBuffer(GL_BACK);
glutSwapBuffers();
#endif
glutPostRedisplay();
}
void bf_est_update(short fill) {
if (fill_count < 1000) {
desired_fill += (double)fill/1000.0;
fill_count++;
return;
}
#define CONTROL_A (1e-4)
#define CONTROL_B (1e-1)
double buf_delta = fill - desired_fill;
bf_est_err = biquad_filt(&bf_err_lpf, buf_delta);
double err_deriv = biquad_filt(&bf_err_deriv_lpf, bf_est_err - bf_last_err);
bf_est_drift = biquad_filt(&bf_drift_lpf, CONTROL_B*(bf_est_err*CONTROL_A + err_deriv) + bf_est_drift);
if (debug)
fprintf(stderr, "bf %d err %f drift %f desiring %f ed %f estd %f\r", fill, bf_est_err, bf_est_drift, desired_fill, err_deriv, err_deriv + CONTROL_A*bf_est_err);
bf_playback_rate = 1.0 + CONTROL_A*bf_est_err + bf_est_drift;
bf_last_err = bf_est_err;
}