#include <stdint.h>
+
#include "ardour/interpolation.h"
using namespace ARDOUR;
nframes_t
-LinearInterpolation::interpolate (nframes_t nframes, Sample *input, Sample *output)
+FixedPointLinearInterpolation::interpolate (int channel, nframes_t nframes, Sample *input, Sample *output)
{
- // the idea is that when the speed is not 1.0, we have to
+ // the idea behind phase is that when the speed is not 1.0, we have to
// interpolate between samples and then we have to store where we thought we were.
// rather than being at sample N or N+1, we were at N+0.8792922
+ // so the "phase" element, if you want to think about this way,
+ // varies from 0 to 1, representing the "offset" between samples
+ uint64_t phase = last_phase[channel];
+
+ // acceleration
+ int64_t phi_delta;
+
+ // phi = fixed point speed
+ if (phi != target_phi) {
+ phi_delta = ((int64_t)(target_phi - phi)) / nframes;
+ } else {
+ phi_delta = 0;
+ }
// index in the input buffers
nframes_t i = 0;
+
+ for (nframes_t outsample = 0; outsample < nframes; ++outsample) {
+ i = phase >> 24;
+ Sample fractional_phase_part = (phase & fractional_part_mask) / binary_scaling_factor;
+
+ if (input && output) {
+ // Linearly interpolate into the output buffer
+ // using fixed point math
+ output[outsample] =
+ input[i] * (1.0f - fractional_phase_part) +
+ input[i+1] * fractional_phase_part;
+ }
+
+ phase += phi + phi_delta;
+ }
+
+ last_phase[channel] = (phase & fractional_part_mask);
+
+ // playback distance
+ return i;
+}
+
+void
+FixedPointLinearInterpolation::add_channel_to (int input_buffer_size, int output_buffer_size)
+{
+ last_phase.push_back (0);
+}
+
+void
+FixedPointLinearInterpolation::remove_channel_from ()
+{
+ last_phase.pop_back ();
+}
+
+void
+FixedPointLinearInterpolation::reset()
+{
+ for(int i = 0; i <= last_phase.size(); i++) {
+ last_phase[i] = 0;
+ }
+}
+
+
+nframes_t
+LinearInterpolation::interpolate (int channel, nframes_t nframes, Sample *input, Sample *output)
+{
+ // index in the input buffers
+ nframes_t i = 0;
double acceleration;
double distance = 0.0;
} else {
acceleration = 0.0;
}
-
+
+ printf("phase before: %lf\n", phase[channel]);
+ distance = phase[channel];
for (nframes_t outsample = 0; outsample < nframes; ++outsample) {
i = distance;
Sample fractional_phase_part = distance - i;
+ if (fractional_phase_part >= 1.0) {
+ fractional_phase_part -= 1.0;
+ i++;
+ }
+ //printf("I: %u, distance: %lf, fractional_phase_part: %lf\n", i, distance, fractional_phase_part);
if (input && output) {
- // Linearly interpolate into the output buffer
+ // Linearly interpolate into the output buffer
output[outsample] =
input[i] * (1.0f - fractional_phase_part) +
input[i+1] * fractional_phase_part;
}
- distance += _speed + acceleration;
+ //printf("distance before: %lf\n", distance);
+ distance += _speed + acceleration;
+ //printf("distance after: %lf, _speed: %lf\n", distance, _speed);
}
- i = (distance + 0.5L);
- // playback distance
+ printf("before assignment: i: %d, distance: %lf\n", i, distance);
+ i = floor(distance);
+ printf("after assignment: i: %d, distance: %16lf\n", i, distance);
+ phase[channel] = distance - floor(distance);
+ printf("speed: %16lf, i after: %d, distance after: %16lf, phase after: %16lf\n", _speed, i, distance, phase[channel]);
+
return i;
}
+
+void
+LinearInterpolation::add_channel_to (int input_buffer_size, int output_buffer_size)
+{
+ phase.push_back (0.0);
+}
+
+void
+LinearInterpolation::remove_channel_from ()
+{
+ phase.pop_back ();
+}
+
+
+void
+LinearInterpolation::reset()
+{
+ for(int i = 0; i <= phase.size(); i++) {
+ phase[i] = 0.0;
+ }
+}
+
+LibSamplerateInterpolation::LibSamplerateInterpolation() : state (0)
+{
+ _speed = 1.0;
+}
+
+LibSamplerateInterpolation::~LibSamplerateInterpolation()
+{
+ for (int i = 0; i < state.size(); i++) {
+ state[i] = src_delete (state[i]);
+ }
+}
+
+void
+LibSamplerateInterpolation::set_speed (double new_speed)
+{
+ _speed = new_speed;
+ for (int i = 0; i < state.size(); i++) {
+ src_set_ratio (state[i], 1.0/_speed);
+ }
+}
+
+void
+LibSamplerateInterpolation::reset_state ()
+{
+ printf("INTERPOLATION: reset_state()\n");
+ for (int i = 0; i < state.size(); i++) {
+ if (state[i]) {
+ src_reset (state[i]);
+ } else {
+ state[i] = src_new (SRC_SINC_FASTEST, 1, &error);
+ }
+ }
+}
+
+void
+LibSamplerateInterpolation::add_channel_to (int input_buffer_size, int output_buffer_size)
+{
+ SRC_DATA* newdata = new SRC_DATA;
+
+ /* Set up sample rate converter info. */
+ newdata->end_of_input = 0 ;
+
+ newdata->input_frames = input_buffer_size;
+ newdata->output_frames = output_buffer_size;
+
+ newdata->input_frames_used = 0 ;
+ newdata->output_frames_gen = 0 ;
+
+ newdata->src_ratio = 1.0/_speed;
+
+ data.push_back (newdata);
+ state.push_back (0);
+
+ reset_state ();
+}
+
+void
+LibSamplerateInterpolation::remove_channel_from ()
+{
+ delete data.back ();
+ data.pop_back ();
+ delete state.back ();
+ state.pop_back ();
+ reset_state ();
+}
+
+nframes_t
+LibSamplerateInterpolation::interpolate (int channel, nframes_t nframes, Sample *input, Sample *output)
+{
+ if (!data.size ()) {
+ printf ("ERROR: trying to interpolate with no channels\n");
+ return 0;
+ }
+
+ data[channel]->data_in = input;
+ data[channel]->data_out = output;
+
+ data[channel]->input_frames = nframes * _speed;
+ data[channel]->output_frames = nframes;
+ data[channel]->src_ratio = 1.0/_speed;
+
+ if ((error = src_process (state[channel], data[channel]))) {
+ printf ("\nError : %s\n\n", src_strerror (error));
+ exit (1);
+ }
+
+ //printf("INTERPOLATION: channel %d input_frames_used: %d\n", channel, data[channel]->input_frames_used);
+
+ return data[channel]->input_frames_used;
+}
projects / ardour.git / blobdiff