Add new subsystem for applying envelopes (such as volume ramps) to audio signals

git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@2082 fefdeb5f-60dc-0310-8127-8f9354f1896f

src/Makefile.am

@@ -253,7 +253,8 @@ noinst_PROGRAMS = \
 		resampler-test \
 		smoother-test \
 		mix-test \
-		remix-test
+		remix-test \
+		envelope-test
 
 if HAVE_SIGXCPU
 noinst_PROGRAMS += \
@@ -418,6 +419,11 @@ smoother_test_LDADD = $(AM_LDADD) libpulsecore.la
 smoother_test_CFLAGS = $(AM_CFLAGS)
 smoother_test_LDFLAGS = $(AM_LDFLAGS) $(BINLDFLAGS)
 
+envelope_test_SOURCES = tests/envelope-test.c
+envelope_test_LDADD = $(AM_LDADD) libpulsecore.la
+envelope_test_CFLAGS = $(AM_CFLAGS) $(LIBOIL_CFLAGS)
+envelope_test_LDFLAGS = $(AM_LDFLAGS) $(BINLDFLAGS) $(LIBOIL_LIBS)
+
 ###################################
 #         Client library          #
 ###################################
@@ -749,6 +755,7 @@ libpulsecore_la_SOURCES += \
 		pulsecore/once.c pulsecore/once.h \
 		pulsecore/time-smoother.c pulsecore/time-smoother.h \
 		pulsecore/start-child.c pulsecore/start-child.h \
+		pulsecore/envelope.c pulsecore/envelope.h \
 		$(PA_THREAD_OBJS)
 
 if OS_IS_WIN32

src/pulsecore/envelope.c

@@ -0,0 +1,783 @@
+/* $Id$ */
+
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2007 Lennart Poettering
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as
+  published by the Free Software Foundation; either version 2.1 of the
+  License, or (at your option) any later version.
+
+  PulseAudio 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with PulseAudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+
+#include <pulse/sample.h>
+#include <pulse/xmalloc.h>
+
+#include <pulsecore/endianmacros.h>
+#include <pulsecore/memchunk.h>
+#include <pulsecore/macro.h>
+#include <pulsecore/flist.h>
+#include <pulsecore/semaphore.h>
+#include <pulsecore/g711.h>
+
+#include "envelope.h"
+
+/*
+    Envelope subsystem for applying linear interpolated volume
+    envelopes on audio data. If multiple enevelopes shall be applied
+    at the same time, the "minimum" envelope is determined and
+    applied.
+
+    Envelopes are defined in a statically allocated constant structure
+    pa_envelope_def. It may be activated using pa_envelope_add(). And
+    already active envelope may be replaced with pa_envelope_replace()
+    and removed with pa_envelope_remove().The combined "minimum"
+    envelope can be applied to audio data with pa_envelope_apply().
+
+    _apply() on one hand and _add()/_replace()/_remove() on the other
+    can be executed in seperate threads, in which case no locking is
+    used.
+*/
+
+PA_STATIC_FLIST_DECLARE(items, 0, pa_xfree);
+
+struct pa_envelope_item {
+    PA_LLIST_FIELDS(pa_envelope_item);
+    const pa_envelope_def *def;
+    pa_usec_t start_x;
+    union {
+        int32_t i;
+        float f;
+    } start_y;
+    unsigned j;
+};
+
+enum envelope_state {
+    STATE_VALID0,
+    STATE_VALID1,
+    STATE_READ0,
+    STATE_READ1,
+    STATE_WAIT0,
+    STATE_WAIT1,
+    STATE_WRITE0,
+    STATE_WRITE1
+};
+
+struct pa_envelope {
+    pa_sample_spec sample_spec;
+
+    PA_LLIST_HEAD(pa_envelope_item, items);
+
+    pa_atomic_t state;
+
+    size_t x;
+
+    struct {
+        unsigned n_points, n_allocated, n_current;
+
+        size_t *x;
+        union {
+            int32_t *i;
+            float *f;
+        } y;
+
+        size_t cached_dx;
+        int32_t cached_dy_i;
+        float cached_dy_dx;
+        pa_bool_t cached_valid;
+    } points[2];
+
+    pa_bool_t is_float;
+
+    pa_semaphore *semaphore;
+};
+
+pa_envelope *pa_envelope_new(const pa_sample_spec *ss) {
+    pa_envelope *e;
+    pa_assert(ss);
+
+    e = pa_xnew(pa_envelope, 1);
+
+    e->sample_spec = *ss;
+    PA_LLIST_HEAD_INIT(pa_envelope_item, e->items);
+
+    e->x = 0;
+
+    e->points[0].n_points = e->points[1].n_points = 0;
+    e->points[0].n_allocated = e->points[1].n_allocated = 0;
+    e->points[0].n_current = e->points[1].n_current = 0;
+    e->points[0].x = e->points[1].x = NULL;
+    e->points[0].y.i = e->points[1].y.i = NULL;
+    e->points[0].cached_valid = e->points[1].cached_valid = FALSE;
+
+    pa_atomic_store(&e->state, STATE_VALID0);
+
+    e->is_float =
+        ss->format == PA_SAMPLE_FLOAT32LE ||
+        ss->format == PA_SAMPLE_FLOAT32BE;
+
+    e->semaphore = pa_semaphore_new(0);
+
+    return e;
+}
+
+void pa_envelope_free(pa_envelope *e) {
+    pa_assert(e);
+
+    while (e->items)
+        pa_envelope_remove(e, e->items);
+
+    pa_xfree(e->points[0].x);
+    pa_xfree(e->points[1].x);
+    pa_xfree(e->points[0].y.i);
+    pa_xfree(e->points[1].y.i);
+
+    pa_semaphore_free(e->semaphore);
+
+    pa_xfree(e);
+}
+
+static int32_t linear_interpolate_int(pa_usec_t x1, int32_t _y1, pa_usec_t x2, int32_t y2, pa_usec_t x3) {
+    return (int32_t) (_y1 + (x3 - x1) * (float) (y2 - _y1) / (float) (x2 - x1));
+}
+
+static float linear_interpolate_float(pa_usec_t x1, float _y1, pa_usec_t x2, float y2, pa_usec_t x3) {
+    return _y1 + (x3 - x1) * (y2 - _y1) / (x2 - x1);
+}
+
+static int32_t item_get_int(pa_envelope_item *i, pa_usec_t x) {
+    pa_assert(i);
+
+    if (x <= i->start_x)
+        return i->start_y.i;
+
+    x -= i->start_x;
+
+    if (x <= i->def->points_x[0])
+        return linear_interpolate_int(0, i->start_y.i,
+                                      i->def->points_x[0], i->def->points_y.i[0], x);
+
+    if (x >= i->def->points_x[i->def->n_points-1])
+        return i->def->points_y.i[i->def->n_points-1];
+
+    pa_assert(i->j > 0);
+    pa_assert(i->def->points_x[i->j-1] <= x);
+    pa_assert(x < i->def->points_x[i->j]);
+
+    return linear_interpolate_int(i->def->points_x[i->j-1], i->def->points_y.i[i->j-1],
+                                  i->def->points_x[i->j], i->def->points_y.i[i->j], x);
+}
+
+static float item_get_float(pa_envelope_item *i, pa_usec_t x) {
+    pa_assert(i);
+
+    if (x <= i->start_x)
+        return i->start_y.f;
+
+    x -= i->start_x;
+
+    if (x <= i->def->points_x[0])
+        return linear_interpolate_float(0, i->start_y.f,
+                                        i->def->points_x[0], i->def->points_y.f[0], x);
+
+    if (x >= i->def->points_x[i->def->n_points-1])
+        return i->def->points_y.f[i->def->n_points-1];
+
+    pa_assert(i->j > 0);
+    pa_assert(i->def->points_x[i->j-1] <= x);
+    pa_assert(x < i->def->points_x[i->j]);
+
+    return linear_interpolate_float(i->def->points_x[i->j-1], i->def->points_y.f[i->j-1],
+                                    i->def->points_x[i->j], i->def->points_y.f[i->j], x);
+}
+
+static void envelope_begin_write(pa_envelope *e, int *v) {
+    enum envelope_state new_state, old_state;
+    pa_bool_t wait_sem;
+
+    pa_assert(e);
+    pa_assert(v);
+
+    for (;;) {
+        do {
+            wait_sem = FALSE;
+            old_state = pa_atomic_load(&e->state);
+
+            switch (old_state) {
+                case STATE_VALID0:
+                    *v = 1;
+                    new_state = STATE_WRITE0;
+                    break;
+                case STATE_VALID1:
+                    *v = 0;
+                    new_state = STATE_WRITE1;
+                    break;
+                case STATE_READ0:
+                    new_state = STATE_WAIT0;
+                    wait_sem = TRUE;
+                    break;
+                case STATE_READ1:
+                    new_state = STATE_WAIT1;
+                    wait_sem = TRUE;
+                    break;
+                default:
+                    pa_assert_not_reached();
+            }
+        } while (!pa_atomic_cmpxchg(&e->state, old_state, new_state));
+
+        if (!wait_sem)
+            break;
+
+        pa_semaphore_wait(e->semaphore);
+    }
+}
+
+static pa_bool_t envelope_commit_write(pa_envelope *e, int v) {
+    enum envelope_state new_state, old_state;
+
+    pa_assert(e);
+
+    do {
+        old_state = pa_atomic_load(&e->state);
+
+        switch (old_state) {
+            case STATE_WRITE0:
+                pa_assert(v == 1);
+                new_state = STATE_VALID1;
+                break;
+            case STATE_WRITE1:
+                pa_assert(v == 0);
+                new_state = STATE_VALID0;
+                break;
+            case STATE_VALID0:
+            case STATE_VALID1:
+            case STATE_READ0:
+            case STATE_READ1:
+                return FALSE;
+            default:
+                pa_assert_not_reached();
+        }
+    } while (!pa_atomic_cmpxchg(&e->state, old_state, new_state));
+
+    return TRUE;
+}
+
+static void envelope_begin_read(pa_envelope *e, int *v) {
+    enum envelope_state new_state, old_state;
+    pa_assert(e);
+    pa_assert(v);
+
+    do {
+        old_state = pa_atomic_load(&e->state);
+
+        switch (old_state) {
+            case STATE_VALID0:
+            case STATE_WRITE0:
+                *v = 0;
+                new_state = STATE_READ0;
+                break;
+            case STATE_VALID1:
+            case STATE_WRITE1:
+                *v = 1;
+                new_state = STATE_READ1;
+                break;
+            default:
+                pa_assert_not_reached();
+        }
+    } while (!pa_atomic_cmpxchg(&e->state, old_state, new_state));
+}
+
+static void envelope_commit_read(pa_envelope *e, int v) {
+    enum envelope_state new_state, old_state;
+    pa_bool_t post_sem;
+
+    pa_assert(e);
+
+    do {
+        post_sem = FALSE;
+        old_state = pa_atomic_load(&e->state);
+
+        switch (old_state) {
+            case STATE_READ0:
+                pa_assert(v == 0);
+                new_state = STATE_VALID0;
+                break;
+            case STATE_READ1:
+                pa_assert(v == 1);
+                new_state = STATE_VALID1;
+                break;
+            case STATE_WAIT0:
+                pa_assert(v == 0);
+                new_state = STATE_VALID0;
+                post_sem = TRUE;
+                break;
+            case STATE_WAIT1:
+                pa_assert(v == 1);
+                new_state = STATE_VALID1;
+                post_sem = TRUE;
+                break;
+            default:
+                pa_assert_not_reached();
+        }
+    } while (!pa_atomic_cmpxchg(&e->state, old_state, new_state));
+
+    if (post_sem)
+        pa_semaphore_post(e->semaphore);
+}
+
+static void envelope_merge(pa_envelope *e, int v) {
+
+    e->points[v].n_points = 0;
+
+    if (e->items) {
+        pa_envelope_item *i;
+        pa_usec_t x = (pa_usec_t) -1;
+
+        for (i = e->items; i; i = i->next)
+            i->j = 0;
+
+        for (;;) {
+            pa_bool_t min_is_set;
+            pa_envelope_item *s = NULL;
+
+            /* Let's find the next spot on the X axis to analyze */
+            for (i = e->items; i; i = i->next) {
+
+                for (;;) {
+
+                    if (i->j >= i->def->n_points)
+                        break;
+
+                    if ((x != (pa_usec_t) -1) && i->start_x + i->def->points_x[i->j] <= x) {
+                        i->j++;
+                        continue;
+                    }
+
+                    if (!s || (i->start_x + i->def->points_x[i->j] < s->start_x + s->def->points_x[s->j]))
+                        s = i;
+
+                    break;
+                }
+            }
+
+            if (!s)
+                break;
+
+            if (e->points[v].n_points >= e->points[v].n_allocated) {
+                e->points[v].n_allocated = MAX(e->points[v].n_points*2, PA_ENVELOPE_POINTS_MAX);
+
+                e->points[v].x = pa_xrealloc(e->points[v].x, sizeof(size_t) * e->points[v].n_allocated);
+                e->points[v].y.i = pa_xrealloc(e->points[v].y.i, sizeof(int32_t) * e->points[v].n_allocated);
+            }
+
+            x = s->start_x + s->def->points_x[s->j];
+            e->points[v].x[e->points[v].n_points] = pa_usec_to_bytes(x, &e->sample_spec);
+
+            min_is_set = FALSE;
+
+            /* Now let's find the lowest value */
+            if (e->is_float) {
+                float min_f;
+
+                for (i = e->items; i; i = i->next) {
+                    float f = item_get_float(i, x);
+                    if (!min_is_set || f < min_f) {
+                        min_f = f;
+                        min_is_set = TRUE;
+                    }
+                }
+
+                e->points[v].y.f[e->points[v].n_points] = min_f;
+            } else {
+                int32_t min_k;
+
+                for (i = e->items; i; i = i->next) {
+                    int32_t k = item_get_int(i, x);
+                    if (!min_is_set || k < min_k) {
+                        min_k = k;
+                        min_is_set = TRUE;
+                    }
+                }
+
+                e->points[v].y.i[e->points[v].n_points] = min_k;
+            }
+
+            pa_assert_se(min_is_set);
+            e->points[v].n_points++;
+        }
+    }
+
+    e->points[v].n_current = 0;
+    e->points[v].cached_valid = FALSE;
+}
+
+pa_envelope_item *pa_envelope_add(pa_envelope *e, const pa_envelope_def *def) {
+    pa_envelope_item *i;
+    int v;
+
+    pa_assert(e);
+    pa_assert(def);
+    pa_assert(def->n_points > 0);
+
+    if (!(i = pa_flist_pop(PA_STATIC_FLIST_GET(items))))
+        i = pa_xnew(pa_envelope_item, 1);
+
+    i->def = def;
+
+    if (e->is_float)
+        i->start_y.f = def->points_y.f[0];
+    else
+        i->start_y.i = def->points_y.i[0];
+
+    PA_LLIST_PREPEND(pa_envelope_item, e->items, i);
+
+    envelope_begin_write(e, &v);
+
+    do {
+
+        i->start_x = pa_bytes_to_usec(e->x, &e->sample_spec);
+        envelope_merge(e, v);
+
+    } while (!envelope_commit_write(e, v));
+
+    return i;
+}
+
+pa_envelope_item *pa_envelope_replace(pa_envelope *e, pa_envelope_item *i, const pa_envelope_def *def) {
+    pa_usec_t x;
+    int v;
+
+    pa_assert(e);
+    pa_assert(i);
+    pa_assert(def->n_points > 0);
+
+    envelope_begin_write(e, &v);
+
+    for (;;) {
+        float saved_f;
+        int32_t saved_i;
+        uint64_t saved_start_x;
+        const pa_envelope_def *saved_def;
+
+        x = pa_bytes_to_usec(e->x, &e->sample_spec);
+
+        if (e->is_float) {
+            saved_f = i->start_y.f;
+            i->start_y.f = item_get_float(i, x);
+        } else {
+            saved_i = i->start_y.i;
+            i->start_y.i = item_get_int(i, x);
+        }
+
+        saved_start_x = i->start_x;
+        saved_def = i->def;
+
+        i->start_x = x;
+        i->def = def;
+
+        envelope_merge(e, v);
+
+        if (envelope_commit_write(e, v))
+            break;
+
+        i->start_x = saved_start_x;
+        i->def = saved_def;
+
+        if (e->is_float)
+            i->start_y.f = saved_f;
+        else
+            i->start_y.i = saved_i;
+    }
+
+    return i;
+}
+
+void pa_envelope_remove(pa_envelope *e, pa_envelope_item *i) {
+    int v;
+
+    pa_assert(e);
+    pa_assert(i);
+
+    PA_LLIST_REMOVE(pa_envelope_item, e->items, i);
+
+    if (pa_flist_push(PA_STATIC_FLIST_GET(items), i) < 0)
+        pa_xfree(i);
+
+    envelope_begin_write(e, &v);
+    do {
+        envelope_merge(e, v);
+    } while (!envelope_commit_write(e, v));
+}
+
+static int32_t linear_get_int(pa_envelope *e, int v) {
+    pa_assert(e);
+
+    /* The repeated division could be replaced by Bresenham, as an
+     * optimization */
+
+    if (e->x < e->points[v].x[0])
+        return e->points[v].y.i[0];
+
+    for (;;) {
+        if (e->points[v].n_current+1 >= e->points[v].n_points)
+            return e->points[v].y.i[e->points[v].n_points-1];
+
+        if (e->x < e->points[v].x[e->points[v].n_current+1])
+            break;
+
+        e->points[v].n_current++;
+        e->points[v].cached_valid = FALSE;
+    }
+
+    if (!e->points[v].cached_valid) {
+        e->points[v].cached_dx = e->points[v].x[e->points[v].n_current+1] - e->points[v].x[e->points[v].n_current];
+        e->points[v].cached_dy_i = e->points[v].y.i[e->points[v].n_current+1] - e->points[v].y.i[e->points[v].n_current];
+        e->points[v].cached_valid = TRUE;
+    }
+
+    return e->points[v].y.i[e->points[v].n_current] + (e->points[v].cached_dy_i * (int32_t) (e->x - e->points[v].x[e->points[v].n_current])) / (int32_t) e->points[v].cached_dx;
+}
+
+static float linear_get_float(pa_envelope *e, int v) {
+    pa_assert(e);
+
+    if (e->x < e->points[v].x[0])
+        return e->points[v].y.f[0];
+
+    for (;;) {
+        if (e->points[v].n_current+1 >= e->points[v].n_points)
+            return e->points[v].y.f[e->points[v].n_points-1];
+
+        if (e->x < e->points[v].x[e->points[v].n_current+1])
+            break;
+
+        e->points[v].n_current++;
+        e->points[v].cached_valid = FALSE;
+    }
+
+    if (!e->points[v].cached_valid) {
+        e->points[v].cached_dy_dx =
+            (e->points[v].y.f[e->points[v].n_current+1] - e->points[v].y.f[e->points[v].n_current]) /
+            (e->points[v].x[e->points[v].n_current+1] - e->points[v].x[e->points[v].n_current]);
+        e->points[v].cached_valid = TRUE;
+    }
+
+    return e->points[v].y.f[e->points[v].n_current] + (e->x - e->points[v].x[e->points[v].n_current]) * e->points[v].cached_dy_dx;
+}
+
+void pa_envelope_apply(pa_envelope *e, pa_memchunk *chunk) {
+    int v;
+
+    pa_assert(e);
+    pa_assert(chunk);
+
+    envelope_begin_read(e, &v);
+
+    if (e->points[v].n_points > 0) {
+        void *p;
+        size_t fs, n;
+
+        pa_memchunk_make_writable(chunk, 0);
+        p = (uint8_t*) pa_memblock_acquire(chunk->memblock) + chunk->index;
+        fs = pa_frame_size(&e->sample_spec);
+        n = chunk->length;
+
+        switch (e->sample_spec.format) {
+
+
+
+            case PA_SAMPLE_U8: {
+                uint8_t *t;
+
+                for (t = p; n > 0; n -= fs) {
+                    int16_t factor = linear_get_int(e, v);
+                    unsigned c;
+                    e->x += fs;
+
+                    for (c = 0; c < e->sample_spec.channels; c++, t++)
+                        *t = (uint8_t) (((factor * ((int16_t) *t - 0x80)) / 0x10000) + 0x80);
+                }
+
+                break;
+            }
+
+            case PA_SAMPLE_ULAW: {
+                uint8_t *t;
+
+                for (t = p; n > 0; n -= fs) {
+                    int16_t factor = linear_get_int(e, v);
+                    unsigned c;
+                    e->x += fs;
+
+                    for (c = 0; c < e->sample_spec.channels; c++, t++) {
+                        int16_t k = st_ulaw2linear16(*t);
+                        *t = (uint8_t) st_14linear2ulaw(((factor * k) / 0x10000) >> 2);
+                    }
+                }
+
+                break;
+            }
+
+            case PA_SAMPLE_ALAW: {
+                uint8_t *t;
+
+                for (t = p; n > 0; n -= fs) {
+                    int16_t factor = linear_get_int(e, v);
+                    unsigned c;
+                    e->x += fs;
+
+                    for (c = 0; c < e->sample_spec.channels; c++, t++) {
+                        int16_t k = st_alaw2linear16(*t);
+                        *t = (uint8_t) st_13linear2alaw(((factor * k) / 0x10000) >> 3);
+                    }
+                }
+
+                break;
+            }
+
+            case PA_SAMPLE_S16NE: {
+                int16_t *t;
+
+                for (t = p; n > 0; n -= fs) {
+                    int32_t factor = linear_get_int(e, v);
+                    unsigned c;
+                    e->x += fs;
+
+                    for (c = 0; c < e->sample_spec.channels; c++, t++)
+                        *t = (factor * *t) / 0x10000;
+                }
+
+                break;
+            }
+
+            case PA_SAMPLE_S16RE: {
+                int16_t *t;
+
+                for (t = p; n > 0; n -= fs) {
+                    int32_t factor = linear_get_int(e, v);
+                    unsigned c;
+                    e->x += fs;
+
+                    for (c = 0; c < e->sample_spec.channels; c++, t++) {
+                        int16_t r = (factor * PA_INT16_SWAP(*t)) / 0x10000;
+                        *t = PA_INT16_SWAP(r);
+                    }
+                }
+
+                break;
+            }
+
+            case PA_SAMPLE_S32NE: {
+                int32_t *t;
+
+                for (t = p; n > 0; n -= fs) {
+                    int32_t factor = linear_get_int(e, v);
+                    unsigned c;
+                    e->x += fs;
+
+                    for (c = 0; c < e->sample_spec.channels; c++, t++)
+                        *t = (int32_t) (((int64_t) factor * (int64_t) *t) / 0x10000);
+                }
+
+                break;
+            }
+
+            case PA_SAMPLE_S32RE: {
+                int32_t *t;
+
+                for (t = p; n > 0; n -= fs) {
+                    int32_t factor = linear_get_int(e, v);
+                    unsigned c;
+                    e->x += fs;
+
+                    for (c = 0; c < e->sample_spec.channels; c++, t++) {
+                        int32_t r = (int32_t) (((int64_t) factor * (int64_t) PA_INT32_SWAP(*t)) / 0x10000);
+                        *t = PA_INT32_SWAP(r);
+                    }
+                }
+
+                break;
+            }
+
+            case PA_SAMPLE_FLOAT32NE: {
+                float *t;
+
+                for (t = p; n > 0; n -= fs) {
+                    float factor = linear_get_float(e, v);
+                    unsigned c;
+                    e->x += fs;
+
+                    for (c = 0; c < e->sample_spec.channels; c++, t++)
+                        *t = *t * factor;
+                }
+
+                break;
+            }
+
+            case PA_SAMPLE_FLOAT32RE: {
+                float *t;
+
+                for (t = p; n > 0; n -= fs) {
+                    float factor = linear_get_float(e, v);
+                    unsigned c;
+                    e->x += fs;
+
+                    for (c = 0; c < e->sample_spec.channels; c++, t++) {
+                        float r = PA_FLOAT32_SWAP(*t) * factor;
+                        *t = PA_FLOAT32_SWAP(r);
+                    }
+                }
+
+                break;
+            }
+
+            case PA_SAMPLE_MAX:
+            case PA_SAMPLE_INVALID:
+                pa_assert_not_reached();
+        }
+
+        pa_memblock_release(chunk->memblock);
+
+        e->x += chunk->length;
+    } else {
+        /* When we have no envelope to apply we reset our origin */
+        e->x = 0;
+    }
+
+    envelope_commit_read(e, v);
+}
+
+void pa_envelope_rewind(pa_envelope *e, size_t n_bytes) {
+    int v;
+
+    pa_assert(e);
+
+    envelope_begin_read(e, &v);
+
+    if (n_bytes < e->x)
+        e->x -= n_bytes;
+    else
+        e->x = 0;
+
+    e->points[v].n_current = 0;
+    e->points[v].cached_valid = FALSE;
+
+    envelope_commit_read(e, v);
+}

src/pulsecore/envelope.h

@@ -0,0 +1,55 @@
+#ifndef foopulseenvelopehfoo
+#define foopulseenvelopehfoo
+
+/* $Id$ */
+
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2007 Lennart Poettering
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as
+  published by the Free Software Foundation; either version 2.1 of the
+  License, or (at your option) any later version.
+
+  PulseAudio 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
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with PulseAudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#include <pulsecore/macro.h>
+#include <pulsecore/memchunk.h>
+
+#include <pulse/sample.h>
+
+#define PA_ENVELOPE_POINTS_MAX 4
+
+typedef struct pa_envelope pa_envelope;
+typedef struct pa_envelope_item pa_envelope_item;
+
+typedef struct pa_envelope_def {
+    unsigned n_points;
+
+    pa_usec_t points_x[PA_ENVELOPE_POINTS_MAX];
+    struct {
+        int32_t i[PA_ENVELOPE_POINTS_MAX];
+        float f[PA_ENVELOPE_POINTS_MAX];
+    } points_y;
+} pa_envelope_def;
+
+pa_envelope *pa_envelope_new(const pa_sample_spec *ss);
+void pa_envelope_free(pa_envelope *e);
+pa_envelope_item *pa_envelope_add(pa_envelope *e, const pa_envelope_def *def);
+pa_envelope_item *pa_envelope_replace(pa_envelope *e, pa_envelope_item *i, const pa_envelope_def *def);
+void pa_envelope_remove(pa_envelope *e, pa_envelope_item *i);
+void pa_envelope_apply(pa_envelope *e, pa_memchunk *chunk);
+void pa_envelope_rewind(pa_envelope *e, size_t n_bytes);
+
+#endif

src/tests/envelope-test.c

@@ -0,0 +1,248 @@
+/* $Id$ */
+
+/***
+  This file is part of PulseAudio.
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as published
+  by the Free Software Foundation; either version 2 of the License,
+  or (at your option) any later version.
+
+  PulseAudio 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 Lesser General Public License
+  along with PulseAudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <pulse/sample.h>
+#include <pulse/volume.h>
+#include <pulse/timeval.h>
+
+#include <pulsecore/envelope.h>
+#include <pulsecore/macro.h>
+#include <pulsecore/endianmacros.h>
+#include <pulsecore/memblock.h>
+#include <pulsecore/sample-util.h>
+
+#include <liboil/liboil.h>
+
+const pa_envelope_def ramp_down = {
+    .n_points = 2,
+    .points_x = { 100*PA_USEC_PER_MSEC, 300*PA_USEC_PER_MSEC },
+    .points_y = {
+        .f = { 1.0, 0.2 },
+        .i = { 0x10000, 0x10000/5 }
+    }
+};
+
+const pa_envelope_def ramp_up = {
+    .n_points = 2,
+    .points_x = { 100*PA_USEC_PER_MSEC, 300*PA_USEC_PER_MSEC },
+    .points_y = {
+        .f = { 0.2, 1.0 },
+        .i = { 0x10000/5, 0x10000 }
+    }
+};
+
+const pa_envelope_def ramp_down2 = {
+    .n_points = 2,
+    .points_x = { 50*PA_USEC_PER_MSEC, 900*PA_USEC_PER_MSEC },
+    .points_y = {
+        .f = { 0.8, 0.7 },
+        .i = { 0x10000*4/5, 0x10000*7/10 }
+    }
+};
+
+const pa_envelope_def ramp_up2 = {
+    .n_points = 2,
+    .points_x = { 50*PA_USEC_PER_MSEC, 900*PA_USEC_PER_MSEC },
+    .points_y = {
+        .f = { 0.7, 0.9 },
+        .i = { 0x10000*7/10, 0x10000*9/10 }
+    }
+};
+
+static void dump_block(const pa_sample_spec *ss, const pa_memchunk *chunk) {
+    void *d;
+    unsigned i;
+
+    static unsigned j = 0;
+
+    d = pa_memblock_acquire(chunk->memblock);
+
+    switch (ss->format) {
+
+        case PA_SAMPLE_U8:
+        case PA_SAMPLE_ULAW:
+        case PA_SAMPLE_ALAW: {
+            uint8_t *u = d;
+
+            for (i = 0; i < chunk->length / pa_frame_size(ss); i++)
+                printf("0x%02x ", *(u++));
+
+            break;
+        }
+
+        case PA_SAMPLE_S16NE:
+        case PA_SAMPLE_S16RE: {
+            int16_t *u = d;
+
+            for (i = 0; i < chunk->length / pa_frame_size(ss); i++)
+                printf("%i\t%i\n", j++, *(u++));
+
+            break;
+        }
+
+        case PA_SAMPLE_S32NE:
+        case PA_SAMPLE_S32RE: {
+            int32_t *u = d;
+
+            for (i = 0; i < chunk->length / pa_frame_size(ss); i++)
+                printf("%i\t%i\n", j++, *(u++));
+
+            break;
+        }
+
+        case PA_SAMPLE_FLOAT32NE:
+        case PA_SAMPLE_FLOAT32RE: {
+            float *u = d;
+
+            for (i = 0; i < chunk->length / pa_frame_size(ss); i++) {
+                printf("%i\t%1.3g\n", j++, PA_MAYBE_FLOAT32_SWAP(ss->format == PA_SAMPLE_FLOAT32RE, *u));
+                u++;
+            }
+
+            break;
+        }
+
+        default:
+            pa_assert_not_reached();
+    }
+
+    printf("\n");
+
+    pa_memblock_release(chunk->memblock);
+}
+
+static pa_memblock * generate_block(pa_mempool *pool, const pa_sample_spec *ss) {
+    pa_memblock *block;
+    void *d;
+    unsigned n_samples;
+
+    block = pa_memblock_new(pool, pa_bytes_per_second(ss));
+    n_samples = pa_memblock_get_length(block) / pa_sample_size(ss);
+
+    d = pa_memblock_acquire(block);
+
+    switch (ss->format) {
+
+        case PA_SAMPLE_S16NE:
+        case PA_SAMPLE_S16RE: {
+            int16_t *i;
+
+            for (i = d; n_samples > 0; n_samples--, i++)
+                *i = 0x7FFF;
+
+            break;
+        }
+
+        case PA_SAMPLE_S32NE:
+        case PA_SAMPLE_S32RE: {
+            int32_t *i;
+
+            for (i = d; n_samples > 0; n_samples--, i++)
+                *i = 0x7FFFFFFF;
+
+            break;
+        }
+
+        case PA_SAMPLE_FLOAT32RE:
+        case PA_SAMPLE_FLOAT32NE: {
+            float *f;
+
+            for (f = d; n_samples > 0; n_samples--, f++)
+                *f = PA_MAYBE_FLOAT32_SWAP(ss->format == PA_SAMPLE_FLOAT32RE, 1.0);
+
+            break;
+        }
+
+        default:
+            pa_assert_not_reached();
+    }
+
+    pa_memblock_release(block);
+    return block;
+}
+
+int main(int argc, char *argv[]) {
+    pa_mempool *pool;
+    pa_memblock *block;
+    pa_memchunk chunk;
+    pa_envelope *envelope;
+    pa_envelope_item *item1, *item2;
+
+    const pa_sample_spec ss = {
+        .format = PA_SAMPLE_S16NE,
+        .channels = 1,
+        .rate = 200
+    };
+
+    const pa_cvolume v = {
+        .channels = 1,
+        .values = { PA_VOLUME_NORM, PA_VOLUME_NORM/2 }
+    };
+
+    oil_init();
+    pa_log_set_maximal_level(PA_LOG_DEBUG);
+
+    pa_assert_se(pool = pa_mempool_new(FALSE));
+    pa_assert_se(envelope = pa_envelope_new(&ss));
+
+    block = generate_block(pool, &ss);
+
+    chunk.memblock = pa_memblock_ref(block);
+    chunk.length = pa_memblock_get_length(block);
+    chunk.index = 0;
+
+    pa_volume_memchunk(&chunk, &ss, &v);
+
+    item1 = pa_envelope_add(envelope, &ramp_down);
+    item2 = pa_envelope_add(envelope, &ramp_down2);
+    pa_envelope_apply(envelope, &chunk);
+    dump_block(&ss, &chunk);
+
+    pa_memblock_unref(chunk.memblock);
+
+    chunk.memblock = pa_memblock_ref(block);
+    chunk.length = pa_memblock_get_length(block);
+    chunk.index = 0;
+
+    item1 = pa_envelope_replace(envelope, item1, &ramp_up);
+    item2 = pa_envelope_replace(envelope, item2, &ramp_up2);
+    pa_envelope_apply(envelope, &chunk);
+    dump_block(&ss, &chunk);
+
+    pa_memblock_unref(chunk.memblock);
+
+    pa_envelope_remove(envelope, item1);
+    pa_envelope_remove(envelope, item2);
+    pa_envelope_free(envelope);
+
+    pa_memblock_unref(block);
+
+    pa_mempool_free(pool);
+
+    return 0;
+}