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-rw-r--r--src/quantiser.c461
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diff --git a/src/quantiser.c b/src/quantiser.c
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+++ b/src/quantiser.c
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+/*
+ An LV2 plugin to quantise an input to a set of fixed values.
+ Copyright 2011 David Robillard
+ Copyright 2003 Mike Rawes
+
+ This is free software: you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This software is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this software. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "lv2/lv2plug.in/ns/lv2core/lv2.h"
+#include "math_func.h"
+#include "common.h"
+
+#define QUANTISER_RANGE_MIN 0
+#define QUANTISER_RANGE_MAX 1
+#define QUANTISER_MATCH_RANGE 2
+#define QUANTISER_MODE 3
+#define QUANTISER_COUNT 4
+#define QUANTISER_VALUE_START 5
+#define QUANTISER_INPUT (QUANTISER_MAX_INPUTS + 5)
+#define QUANTISER_OUTPUT (QUANTISER_MAX_INPUTS + 6)
+#define QUANTISER_OUTPUT_CHANGED (QUANTISER_MAX_INPUTS + 7)
+
+typedef struct {
+ const float* min;
+ const float* max;
+ const float* match_range;
+ const float* mode;
+ const float* count;
+ const float* values[QUANTISER_MAX_INPUTS];
+ const float* input;
+ float* output_changed;
+ float* output;
+ float svalues[QUANTISER_MAX_INPUTS + 2];
+ float temp[QUANTISER_MAX_INPUTS + 2];
+ float last_found;
+} Quantiser;
+
+/*
+ * f <= m <= l
+*/
+static inline void
+merge(float* v,
+ int f,
+ int m,
+ int l,
+ float* temp)
+{
+ int f1 = f;
+ int l1 = m;
+ int f2 = m + 1;
+ int l2 = l;
+ int i = f1;
+
+ while ((f1 <= l1) && (f2 <= l2)) {
+ if (v[f1] < v[f2]) {
+ temp[i] = v[f1];
+ f1++;
+ } else {
+ temp[i] = v[f2];
+ f2++;
+ }
+ i++;
+ }
+ while (f1 <= l1) {
+ temp[i] = v[f1];
+ f1++;
+ i++;
+ }
+ while (f2 <= l2) {
+ temp[i] = v[f2];
+ f2++;
+ i++;
+ }
+ for (i = f; i <= l; i++) {
+ v[i] = temp[i];
+ }
+}
+
+/*
+ * Recursive Merge Sort
+ * Sort elements in unsorted vector v
+*/
+static inline void
+msort(float* v,
+ int f,
+ int l,
+ float* temp)
+{
+ int m;
+
+ if (f < l) {
+ m = (f + l) / 2;
+ msort(v, f, m, temp);
+ msort(v, m + 1, l, temp);
+ merge(v, f, m, l, temp);
+ }
+}
+
+/*
+ * Binary search for nearest match to sought value in
+ * ordered vector v of given size
+*/
+static inline int
+fuzzy_bsearch(float* v,
+ int size,
+ float sought)
+{
+ int f = 0;
+ int l = size - 1;
+ int m = ((l - f) / 2);
+
+ while ((l - f) > 1) {
+ if (v[m] < sought) {
+ f = (l - f) / 2 + f;
+ } else {
+ l = (l - f) / 2 + f;
+ }
+
+ m = ((l - f) / 2 + f);
+ }
+
+ if (sought < v[m]) {
+ if (m > 0) {
+ if (FABSF(v[m] - sought) > FABSF(v[m - 1] - sought)) {
+ m--;
+ }
+ }
+ } else if (m < size - 1) {
+ if (FABSF(v[m] - sought) > FABSF(v[m + 1] - sought)) {
+ m++;
+ }
+ }
+
+ return m;
+}
+
+static void
+cleanup(LV2_Handle instance)
+{
+ free(instance);
+}
+
+static void
+activate(LV2_Handle instance)
+{
+ Quantiser* plugin = (Quantiser*)instance;
+
+ plugin->last_found = 0.0f;
+}
+
+static void
+connect_port(LV2_Handle instance,
+ uint32_t port,
+ void* data)
+{
+ Quantiser* plugin = (Quantiser*)instance;
+
+ switch (port) {
+ case QUANTISER_RANGE_MIN:
+ plugin->min = (const float*)data;
+ break;
+ case QUANTISER_RANGE_MAX:
+ plugin->max = (const float*)data;
+ break;
+ case QUANTISER_MATCH_RANGE:
+ plugin->match_range = (const float*)data;
+ break;
+ case QUANTISER_MODE:
+ plugin->mode = (const float*)data;
+ break;
+ case QUANTISER_COUNT:
+ plugin->count = (const float*)data;
+ break;
+ case QUANTISER_INPUT:
+ plugin->input = (const float*)data;
+ break;
+ case QUANTISER_OUTPUT:
+ plugin->output = (float*)data;
+ break;
+ case QUANTISER_OUTPUT_CHANGED:
+ plugin->output_changed = (float*)data;
+ break;
+ default:
+ if (port >= QUANTISER_VALUE_START && port < QUANTISER_OUTPUT) {
+ plugin->values[port - QUANTISER_VALUE_START] = (float*)data;
+ }
+ break;
+ }
+}
+
+static LV2_Handle
+instantiate(const LV2_Descriptor* descriptor,
+ double sample_rate,
+ const char* bundle_path,
+ const LV2_Feature* const* features)
+{
+ Quantiser* plugin = (Quantiser*)malloc(sizeof(Quantiser));
+
+ return (LV2_Handle)plugin;
+}
+
+static void
+run(LV2_Handle instance,
+ uint32_t sample_count)
+{
+ Quantiser* plugin = (Quantiser*)instance;
+
+ /* Range Min (float value) */
+ float min = *(plugin->min);
+
+ /* Range Max (float value) */
+ float max = *(plugin->max);
+
+ /* Match Range (float value) */
+ const float match_range = FABSF(*(plugin->match_range));
+
+ /* Mode (float value) */
+ const float mode = *(plugin->mode);
+
+ /* Count (float value) */
+ const float count = *(plugin->count);
+
+ /* Input (array of float of length sample_count) */
+ const float* input = plugin->input;
+
+ /* Output (array of float of length sample_count) */
+ float* output = plugin->output;
+
+ /* Output Changed (array of float of length sample_count) */
+ float* output_changed = plugin->output_changed;
+
+ /* Instance Data */
+ float* temp = plugin->temp;
+ float* values = plugin->svalues;
+ float last_found = plugin->last_found;
+
+ int md = LRINTF(mode);
+ int n = LRINTF(count);
+ int i;
+ float in;
+ float out_changed;
+ float range;
+ float offset;
+ float found = last_found;
+ int found_index = 0;
+
+ /* Clip count if out of range */
+ n = n < 1 ? 1 : (n > QUANTISER_MAX_INPUTS ? QUANTISER_MAX_INPUTS : n);
+
+ /* Swap min and max if wrong way around */
+ if (min > max) {
+ range = min;
+ min = max;
+ max = range;
+ }
+ range = max - min;
+
+ /* Copy and sort required values */
+ for (i = 0; i < n; i++) {
+ values[i + 1] = *(plugin->values[i]);
+ }
+
+ msort(values, 1, n, temp);
+
+ /* Add wrapped extremes */
+ values[0] = values[n] - range;
+ values[n + 1] = values[1] + range;
+
+ if (md < 1) {
+ /* Extend mode */
+ for (uint32_t s = 0; s < sample_count; ++s) {
+ in = input[s];
+
+ if (range > 0.0f) {
+ if ((in < min) || (in > max)) {
+ offset = FLOORF((in - max) / range) + 1.0f;
+ offset *= range;
+ in -= offset;
+
+ /* Quantise */
+ found_index = fuzzy_bsearch(values, n + 2, in);
+
+ /* Wrapped */
+ if (found_index == 0) {
+ found_index = n;
+ offset -= range;
+ } else if (found_index == n + 1) {
+ found_index = 1;
+ offset += range;
+ }
+
+ found = values[found_index];
+
+ /* Allow near misses */
+ if (match_range > 0.0f) {
+ if (in < (found - match_range)) {
+ found -= match_range;
+ } else if (in > (found + match_range)) {
+ found += match_range;
+ }
+ }
+ found += offset;
+ } else {
+ /* Quantise */
+ found_index = fuzzy_bsearch(values, n + 2, in);
+ if (found_index == 0) {
+ found_index = n;
+ found = values[n] - range;
+ } else if (found_index == n + 1) {
+ found_index = 1;
+ found = values[1] + range;
+ } else {
+ found = values[found_index];
+ }
+
+ if (match_range > 0.0f) {
+ if (in < (found - match_range)) {
+ found -= match_range;
+ } else if (in > (found + match_range)) {
+ found += match_range;
+ }
+ }
+ }
+ } else {
+ /* Min and max the same, so only one value to quantise to */
+ found = min;
+ }
+
+ /* Has quantised output changed? */
+ if (FABSF(found - last_found) > 2.0001f * match_range) {
+ out_changed = 1.0f;
+ last_found = found;
+ } else {
+ out_changed = 0.0f;
+ }
+
+ output[s] = found;
+ output_changed[s] = out_changed;
+ }
+ } else if (md == 1) {
+ /* Wrap mode */
+ for (uint32_t s = 0; s < sample_count; ++s) {
+ in = input[s];
+
+ if (range > 0.0f) {
+ if ((in < min) || (in > max)) {
+ in -= (FLOORF((in - max) / range) + 1.0f) * range;
+ }
+
+ /* Quantise */
+ found_index = fuzzy_bsearch(values, n + 2, in);
+ if (found_index == 0) {
+ found_index = n;
+ } else if (found_index == n + 1) {
+ found_index = 1;
+ }
+
+ found = values[found_index];
+
+ /* Allow near misses */
+ if (match_range > 0.0f) {
+ if (in < (found - match_range)) {
+ found -= match_range;
+ } else if (in > (found + match_range)) {
+ found += match_range;
+ }
+ }
+ } else {
+ /* Min and max the same, so only one value to quantise to */
+ found = min;
+ }
+
+ /* Has quantised output changed? */
+ if (FABSF(found - last_found) > match_range) {
+ out_changed = 1.0f;
+ last_found = found;
+ } else {
+ out_changed = 0.0f;
+ }
+
+ output[s] = found;
+ output_changed[s] = out_changed;
+ }
+ } else {
+ /* Clip mode */
+ for (uint32_t s = 0; s < sample_count; ++s) {
+ in = input[s];
+
+ if (range > 0.0f) {
+ /* Clip to range */
+ if (in < min) {
+ found_index = 1;
+ } else if (in > max) {
+ found_index = n;
+ } else {
+ /* Quantise */
+ found_index = fuzzy_bsearch(values + 1, n, in) + 1;
+ }
+
+ found = values[found_index];
+
+ /* Allow near misses */
+ if (match_range > 0.0f) {
+ if (in < (found - match_range)) {
+ found -= match_range;
+ } else if (in > (found + match_range)) {
+ found += match_range;
+ }
+ }
+ } else {
+ /* Min and max the same, so only one value to quantise to */
+ found = min;
+ }
+
+ /* Has quantised output changed? */
+ if (FABSF(found - last_found) > match_range) {
+ out_changed = 1.0f;
+ last_found = found;
+ } else {
+ out_changed = 0.0f;
+ }
+
+ output[s] = found;
+ output_changed[s] = out_changed;
+ }
+ }
+ plugin->last_found = last_found;
+}
+
+static const LV2_Descriptor descriptor = {
+ QUANTISER_URI,
+ instantiate,
+ connect_port,
+ activate,
+ run,
+ NULL,
+ cleanup,
+ NULL
+};
+
+LV2_SYMBOL_EXPORT const LV2_Descriptor*
+lv2_descriptor(uint32_t index)
+{
+ switch (index) {
+ case 0: return &descriptor;
+ default: return NULL;
+ }
+}
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