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From c28b5faa6745b525c11d1f54d8bf52386a90fcc1 Mon Sep 17 00:00:00 2001
From: Sangchul Lee <sangchul1011@gmail.com>
Date: Sat, 27 Aug 2016 21:33:16 +0900
Subject: [PATCH 2/6] volume ramp: additions to the low level infra

The original patch is
 - https://review.tizen.org/git/?p=platform/upstream/pulseaudio.git;a=commit;h=df1c4275ed79e0b708c75b92f9d247e0492bc1f0
 - by Jaska Uimonen <jaska.uimonen <at> helsinki.fi>

Signed-off-by: Sangchul Lee <sc11.lee@samsung.com>

---
 src/map-file        |   4 +
 src/pulse/def.h     |  13 ++-
 src/pulse/volume.c  |  74 ++++++++++++-
 src/pulse/volume.h  |  33 ++++++
 src/pulsecore/mix.c | 310 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/pulsecore/mix.h |  27 +++++
 6 files changed, 459 insertions(+), 2 deletions(-)

diff --git a/src/map-file b/src/map-file
index 9b6cba2..946ab54 100644
--- a/src/map-file
+++ b/src/map-file
@@ -138,6 +138,10 @@ pa_cvolume_max_mask;
 pa_cvolume_merge;
 pa_cvolume_min;
 pa_cvolume_min_mask;
+pa_cvolume_ramp_equal;
+pa_cvolume_ramp_init;
+pa_cvolume_ramp_set;
+pa_cvolume_ramp_channel_ramp_set;
 pa_cvolume_remap;
 pa_cvolume_scale;
 pa_cvolume_scale_mask;
diff --git a/src/pulse/def.h b/src/pulse/def.h
index 100df5b..b13eed7 100644
--- a/src/pulse/def.h
+++ b/src/pulse/def.h
@@ -349,11 +349,15 @@ typedef enum pa_stream_flags {
      * consider absolute when the sink is in flat volume mode,
      * relative otherwise. \since 0.9.20 */
 
-    PA_STREAM_PASSTHROUGH = 0x80000U
+    PA_STREAM_PASSTHROUGH = 0x80000U,
     /**< Used to tag content that will be rendered by passthrough sinks.
      * The data will be left as is and not reformatted, resampled.
      * \since 1.0 */
 
+    PA_STREAM_START_RAMP_MUTED = 0x100000U
+    /**< Used to tag content that the stream will be started ramp volume
+     * muted so that you can nicely fade it in */
+
 } pa_stream_flags_t;
 
 /** \cond fulldocs */
@@ -382,6 +386,7 @@ typedef enum pa_stream_flags {
 #define PA_STREAM_FAIL_ON_SUSPEND PA_STREAM_FAIL_ON_SUSPEND
 #define PA_STREAM_RELATIVE_VOLUME PA_STREAM_RELATIVE_VOLUME
 #define PA_STREAM_PASSTHROUGH PA_STREAM_PASSTHROUGH
+#define PA_STREAM_START_RAMP_MUTED PA_STREAM_START_RAMP_MUTED
 
 /** \endcond */
 
@@ -1070,6 +1075,12 @@ typedef enum pa_port_available {
 /** \endcond */
 #endif
 
+/** \cond fulldocs */
+#define PA_VOLUMER_RAMP_TYPE_LINEAR PA_VOLUMER_RAMP_TYPE_LINEAR
+#define PA_VOLUMER_RAMP_TYPE_LOGARITHMIC PA_VOLUMER_RAMP_TYPE_LOGARITHMIC
+#define PA_VOLUMER_RAMP_TYPE_CUBIC PA_VOLUMER_RAMP_TYPE_CUBIC
+/** \endcond */
+
 PA_C_DECL_END
 
 #endif
diff --git a/src/pulse/volume.c b/src/pulse/volume.c
index ead5415..83a1e05 100644
--- a/src/pulse/volume.c
+++ b/src/pulse/volume.c
@@ -457,7 +457,10 @@ int pa_cvolume_channels_equal_to(const pa_cvolume *a, pa_volume_t v) {
     unsigned c;
     pa_assert(a);
 
-    pa_return_val_if_fail(pa_cvolume_valid(a), 0);
+    if (pa_cvolume_valid(a) == 0)
+        abort();
+
+    /* pa_return_val_if_fail(pa_cvolume_valid(a), 0); */
     pa_return_val_if_fail(PA_VOLUME_IS_VALID(v), 0);
 
     for (c = 0; c < a->channels; c++)
@@ -989,3 +992,72 @@ pa_cvolume* pa_cvolume_dec(pa_cvolume *v, pa_volume_t dec) {
 
     return pa_cvolume_scale(v, m);
 }
+
+int pa_cvolume_ramp_equal(const pa_cvolume_ramp *a, const pa_cvolume_ramp *b) {
+    int i;
+    pa_assert(a);
+    pa_assert(b);
+
+    if (PA_UNLIKELY(a == b))
+        return 1;
+
+    if (a->channels != b->channels)
+        return 0;
+
+    for (i = 0; i < a->channels; i++) {
+        if (a->ramps[i].type != b->ramps[i].type ||
+            a->ramps[i].length != b->ramps[i].length ||
+            a->ramps[i].target != b->ramps[i].target)
+            return 0;
+    }
+
+    return 1;
+}
+
+pa_cvolume_ramp* pa_cvolume_ramp_init(pa_cvolume_ramp *ramp) {
+    unsigned c;
+
+    pa_assert(ramp);
+
+    ramp->channels = 0;
+
+    for (c = 0; c < PA_CHANNELS_MAX; c++) {
+        ramp->ramps[c].type = PA_VOLUME_RAMP_TYPE_LINEAR;
+        ramp->ramps[c].length = 0;
+        ramp->ramps[c].target = PA_VOLUME_INVALID;
+    }
+
+    return ramp;
+}
+
+pa_cvolume_ramp* pa_cvolume_ramp_set(pa_cvolume_ramp *ramp, unsigned channels, pa_volume_ramp_type_t type, long time, pa_volume_t vol) {
+    int i;
+
+    pa_assert(ramp);
+    pa_assert(channels > 0);
+    pa_assert(time >= 0);
+    pa_assert(channels <= PA_CHANNELS_MAX);
+
+    ramp->channels = (uint8_t) channels;
+
+    for (i = 0; i < ramp->channels; i++) {
+        ramp->ramps[i].type = type;
+        ramp->ramps[i].length = time;
+        ramp->ramps[i].target = PA_CLAMP_VOLUME(vol);
+    }
+
+    return ramp;
+}
+
+pa_cvolume_ramp* pa_cvolume_ramp_channel_ramp_set(pa_cvolume_ramp *ramp, unsigned channel, pa_volume_ramp_type_t type, long time, pa_volume_t vol) {
+
+    pa_assert(ramp);
+    pa_assert(channel <= ramp->channels);
+    pa_assert(time >= 0);
+
+    ramp->ramps[channel].type = type;
+    ramp->ramps[channel].length = time;
+    ramp->ramps[channel].target = PA_CLAMP_VOLUME(vol);
+
+    return ramp;
+}
diff --git a/src/pulse/volume.h b/src/pulse/volume.h
index 2503c3f..0b74833 100644
--- a/src/pulse/volume.h
+++ b/src/pulse/volume.h
@@ -437,6 +437,39 @@ pa_cvolume* pa_cvolume_inc(pa_cvolume *v, pa_volume_t inc);
  * the channels are kept. Returns \a v, or NULL on error. \since 0.9.16 */
 pa_cvolume* pa_cvolume_dec(pa_cvolume *v, pa_volume_t dec);
 
+/** Volume ramp type
+*/
+typedef enum pa_volume_ramp_type {
+    PA_VOLUME_RAMP_TYPE_LINEAR = 0,        /**< linear */
+    PA_VOLUME_RAMP_TYPE_LOGARITHMIC = 1,   /**< logarithmic */
+    PA_VOLUME_RAMP_TYPE_CUBIC = 2,
+} pa_volume_ramp_type_t;
+
+/** A structure encapsulating a volume ramp */
+typedef struct pa_volume_ramp_t {
+    pa_volume_ramp_type_t type;
+    long length;
+    pa_volume_t target;
+} pa_volume_ramp_t;
+
+/** A structure encapsulating a multichannel volume ramp */
+typedef struct pa_cvolume_ramp {
+    uint8_t channels;
+    pa_volume_ramp_t ramps[PA_CHANNELS_MAX];
+} pa_cvolume_ramp;
+
+/** Return non-zero when *a == *b */
+int pa_cvolume_ramp_equal(const pa_cvolume_ramp *a, const pa_cvolume_ramp *b);
+
+/** Init volume ramp struct */
+pa_cvolume_ramp* pa_cvolume_ramp_init(pa_cvolume_ramp *ramp);
+
+/** Set first n channels of ramp struct to certain value */
+pa_cvolume_ramp* pa_cvolume_ramp_set(pa_cvolume_ramp *ramp, unsigned channel, pa_volume_ramp_type_t type, long time, pa_volume_t vol);
+
+/** Set individual channel in the channel struct */
+pa_cvolume_ramp* pa_cvolume_ramp_channel_ramp_set(pa_cvolume_ramp *ramp, unsigned channel, pa_volume_ramp_type_t type, long time, pa_volume_t vol);
+
 PA_C_DECL_END
 
 #endif
diff --git a/src/pulsecore/mix.c b/src/pulsecore/mix.c
index 59622d7..1e4cc1e 100644
--- a/src/pulsecore/mix.c
+++ b/src/pulsecore/mix.c
@@ -724,3 +724,313 @@ void pa_volume_memchunk(
 
     pa_memblock_release(c->memblock);
 }
+
+static void calc_linear_integer_volume_no_mapping(int32_t linear[], float volume[], unsigned nchannels) {
+    unsigned channel, padding;
+
+    pa_assert(linear);
+    pa_assert(volume);
+
+    for (channel = 0; channel < nchannels; channel++)
+        linear[channel] = (int32_t) lrint(volume[channel] * 0x10000U);
+
+    for (padding = 0; padding < VOLUME_PADDING; padding++, channel++)
+        linear[channel] = linear[padding];
+}
+
+static void calc_linear_float_volume_no_mapping(float linear[], float volume[], unsigned nchannels) {
+    unsigned channel, padding;
+
+    pa_assert(linear);
+    pa_assert(volume);
+
+    for (channel = 0; channel < nchannels; channel++)
+        linear[channel] = volume[channel];
+
+    for (padding = 0; padding < VOLUME_PADDING; padding++, channel++)
+        linear[channel] = linear[padding];
+}
+
+typedef void (*pa_calc_volume_no_mapping_func_t) (void *volumes, float *volume, int channels);
+
+static const pa_calc_volume_no_mapping_func_t calc_volume_table_no_mapping[] = {
+  [PA_SAMPLE_U8]        = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping,
+  [PA_SAMPLE_ALAW]      = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping,
+  [PA_SAMPLE_ULAW]      = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping,
+  [PA_SAMPLE_S16LE]     = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping,
+  [PA_SAMPLE_S16BE]     = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping,
+  [PA_SAMPLE_FLOAT32LE] = (pa_calc_volume_no_mapping_func_t) calc_linear_float_volume_no_mapping,
+  [PA_SAMPLE_FLOAT32BE] = (pa_calc_volume_no_mapping_func_t) calc_linear_float_volume_no_mapping,
+  [PA_SAMPLE_S32LE]     = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping,
+  [PA_SAMPLE_S32BE]     = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping,
+  [PA_SAMPLE_S24LE]     = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping,
+  [PA_SAMPLE_S24BE]     = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping,
+  [PA_SAMPLE_S24_32LE]  = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping,
+  [PA_SAMPLE_S24_32BE]  = (pa_calc_volume_no_mapping_func_t) calc_linear_integer_volume_no_mapping
+};
+
+static const unsigned format_sample_size_table[] = {
+  [PA_SAMPLE_U8]        = 1,
+  [PA_SAMPLE_ALAW]      = 1,
+  [PA_SAMPLE_ULAW]      = 1,
+  [PA_SAMPLE_S16LE]     = 2,
+  [PA_SAMPLE_S16BE]     = 2,
+  [PA_SAMPLE_FLOAT32LE] = 4,
+  [PA_SAMPLE_FLOAT32BE] = 4,
+  [PA_SAMPLE_S32LE]     = 4,
+  [PA_SAMPLE_S32BE]     = 4,
+  [PA_SAMPLE_S24LE]     = 3,
+  [PA_SAMPLE_S24BE]     = 3,
+  [PA_SAMPLE_S24_32LE]  = 4,
+  [PA_SAMPLE_S24_32BE]  = 4
+};
+
+static float calc_volume_ramp_linear(pa_volume_ramp_int_t *ramp) {
+    pa_assert(ramp);
+    pa_assert(ramp->length > 0);
+
+    /* basic linear interpolation */
+    return ramp->start + (ramp->length - ramp->left) * (ramp->end - ramp->start) / (float) ramp->length;
+}
+
+static float calc_volume_ramp_logarithmic(pa_volume_ramp_int_t *ramp) {
+    float x_val, s, e;
+    long temp;
+
+    pa_assert(ramp);
+    pa_assert(ramp->length > 0);
+
+    if (ramp->end > ramp->start) {
+        temp = ramp->left;
+        s = ramp->end;
+        e = ramp->start;
+    } else {
+        temp = ramp->length - ramp->left;
+        s = ramp->start;
+        e = ramp->end;
+    }
+
+    x_val = temp == 0 ? 0.0 : powf(temp, 10);
+
+    /* base 10 logarithmic interpolation */
+    return s + x_val * (e - s) / powf(ramp->length, 10);
+}
+
+static float calc_volume_ramp_cubic(pa_volume_ramp_int_t *ramp) {
+    float x_val, s, e;
+    long temp;
+
+    pa_assert(ramp);
+    pa_assert(ramp->length > 0);
+
+    if (ramp->end > ramp->start) {
+        temp = ramp->left;
+        s = ramp->end;
+        e = ramp->start;
+    } else {
+        temp = ramp->length - ramp->left;
+        s = ramp->start;
+        e = ramp->end;
+    }
+
+    x_val = temp == 0 ? 0.0 : cbrtf(temp);
+
+    /* cubic interpolation */
+    return s + x_val * (e - s) / cbrtf(ramp->length);
+}
+
+typedef float (*pa_calc_volume_ramp_func_t) (pa_volume_ramp_int_t *);
+
+static const pa_calc_volume_ramp_func_t calc_volume_ramp_table[] = {
+    [PA_VOLUME_RAMP_TYPE_LINEAR] = (pa_calc_volume_ramp_func_t) calc_volume_ramp_linear,
+    [PA_VOLUME_RAMP_TYPE_LOGARITHMIC] = (pa_calc_volume_ramp_func_t) calc_volume_ramp_logarithmic,
+    [PA_VOLUME_RAMP_TYPE_CUBIC] = (pa_calc_volume_ramp_func_t) calc_volume_ramp_cubic
+};
+
+static void calc_volume_ramps(pa_cvolume_ramp_int *ram, float *vol)
+{
+    int i;
+
+    for (i = 0; i < ram->channels; i++) {
+        if (ram->ramps[i].left <= 0) {
+            if (ram->ramps[i].target == PA_VOLUME_NORM) {
+                vol[i] = 1.0;
+            }
+        } else {
+            vol[i] = ram->ramps[i].curr = calc_volume_ramp_table[ram->ramps[i].type] (&ram->ramps[i]);
+            ram->ramps[i].left--;
+        }
+    }
+}
+
+void pa_volume_ramp_memchunk(
+        pa_memchunk *c,
+        const pa_sample_spec *spec,
+        pa_cvolume_ramp_int *ramp) {
+
+    void *ptr;
+    volume_val linear[PA_CHANNELS_MAX + VOLUME_PADDING];
+    float vol[PA_CHANNELS_MAX + VOLUME_PADDING];
+    pa_do_volume_func_t do_volume;
+    long length_in_frames;
+    int i;
+
+    pa_assert(c);
+    pa_assert(spec);
+    pa_assert(pa_frame_aligned(c->length, spec));
+    pa_assert(ramp);
+
+    length_in_frames = c->length / format_sample_size_table[spec->format] / spec->channels;
+
+    if (pa_memblock_is_silence(c->memblock)) {
+        for (i = 0; i < ramp->channels; i++) {
+            if (ramp->ramps[i].length > 0)
+                ramp->ramps[i].length -= length_in_frames;
+        }
+        return;
+    }
+
+    if (spec->format < 0 || spec->format >= PA_SAMPLE_MAX) {
+      pa_log_warn("Unable to change volume of format");
+      return;
+    }
+
+    do_volume = pa_get_volume_func(spec->format);
+    pa_assert(do_volume);
+
+    ptr = (uint8_t*) pa_memblock_acquire(c->memblock) + c->index;
+
+    for (i = 0; i < length_in_frames; i++) {
+        calc_volume_ramps(ramp, vol);
+        calc_volume_table_no_mapping[spec->format] ((void *)linear, vol, spec->channels);
+
+        /* we only process one frame per iteration */
+        do_volume (ptr, (void *)linear, spec->channels, format_sample_size_table[spec->format] * spec->channels);
+
+        /* pa_log_debug("1: %d  2: %d", linear[0], linear[1]); */
+
+        ptr = (uint8_t*)ptr + format_sample_size_table[spec->format] * spec->channels;
+    }
+
+    pa_memblock_release(c->memblock);
+}
+
+pa_cvolume_ramp_int* pa_cvolume_ramp_convert(const pa_cvolume_ramp *src, pa_cvolume_ramp_int *dst, int sample_rate) {
+
+    int i, j, channels, remaining_channels;
+    float temp;
+
+    if (dst->channels < src->channels) {
+        channels = dst->channels;
+        remaining_channels = 0;
+    }
+    else {
+        channels = src->channels;
+        remaining_channels = dst->channels;
+    }
+
+    for (i = 0; i < channels; i++) {
+        dst->ramps[i].type = src->ramps[i].type;
+        /* ms to samples */
+        dst->ramps[i].length = src->ramps[i].length * sample_rate / 1000;
+        dst->ramps[i].left = dst->ramps[i].length;
+        dst->ramps[i].start = dst->ramps[i].end;
+        dst->ramps[i].target = src->ramps[i].target;
+        /* scale to pulse internal mapping so that when ramp is over there's no glitch in volume */
+        temp = src->ramps[i].target / (float)0x10000U;
+        dst->ramps[i].end = temp * temp * temp;
+    }
+
+    j = i;
+
+    for (i--; j < remaining_channels; j++) {
+        dst->ramps[j].type = dst->ramps[i].type;
+        dst->ramps[j].length = dst->ramps[i].length;
+        dst->ramps[j].left = dst->ramps[i].left;
+        dst->ramps[j].start = dst->ramps[i].start;
+        dst->ramps[j].target = dst->ramps[i].target;
+        dst->ramps[j].end = dst->ramps[i].end;
+    }
+
+    return dst;
+}
+
+bool pa_cvolume_ramp_active(pa_cvolume_ramp_int *ramp) {
+    int i;
+
+    for (i = 0; i < ramp->channels; i++) {
+        if (ramp->ramps[i].left > 0)
+            return true;
+    }
+
+    return false;
+}
+
+bool pa_cvolume_ramp_target_active(pa_cvolume_ramp_int *ramp) {
+    int i;
+
+    for (i = 0; i < ramp->channels; i++) {
+        if (ramp->ramps[i].target != PA_VOLUME_NORM)
+            return true;
+    }
+
+    return false;
+}
+
+pa_cvolume * pa_cvolume_ramp_get_targets(pa_cvolume_ramp_int *ramp, pa_cvolume *volume) {
+    int i = 0;
+
+    volume->channels = ramp->channels;
+
+    for (i = 0; i < ramp->channels; i++)
+        volume->values[i] = ramp->ramps[i].target;
+
+    return volume;
+}
+
+pa_cvolume_ramp_int* pa_cvolume_ramp_start_from(pa_cvolume_ramp_int *src, pa_cvolume_ramp_int *dst) {
+    int i;
+
+    for (i = 0; i < src->channels; i++) {
+        /* if new vols are invalid, copy old ramp i.e. no effect */
+        if (dst->ramps[i].target == PA_VOLUME_INVALID)
+            dst->ramps[i] = src->ramps[i];
+        /* if there's some old ramp still left */
+        else if (src->ramps[i].left > 0)
+            dst->ramps[i].start = src->ramps[i].curr;
+    }
+
+    return dst;
+}
+
+pa_cvolume_ramp_int* pa_cvolume_ramp_int_init(pa_cvolume_ramp_int *src, pa_volume_t vol, int channels) {
+    int i;
+    float temp;
+
+    src->channels = channels;
+
+    for (i = 0; i < channels; i++) {
+        src->ramps[i].type = PA_VOLUME_RAMP_TYPE_LINEAR;
+        src->ramps[i].length = 0;
+        src->ramps[i].left = 0;
+        if (vol == PA_VOLUME_NORM) {
+            src->ramps[i].start = 1.0;
+            src->ramps[i].end = 1.0;
+            src->ramps[i].curr = 1.0;
+        }
+        else if (vol == PA_VOLUME_MUTED) {
+            src->ramps[i].start = 0.0;
+            src->ramps[i].end = 0.0;
+            src->ramps[i].curr = 0.0;
+        }
+        else {
+            temp = vol / (float)0x10000U;
+            src->ramps[i].start = temp * temp * temp;
+            src->ramps[i].end = src->ramps[i].start;
+            src->ramps[i].curr = src->ramps[i].start;
+        }
+        src->ramps[i].target = vol;
+    }
+
+    return src;
+}
diff --git a/src/pulsecore/mix.h b/src/pulsecore/mix.h
index 8102bcd..0f86b6f 100644
--- a/src/pulsecore/mix.h
+++ b/src/pulsecore/mix.h
@@ -59,4 +59,31 @@ void pa_volume_memchunk(
     const pa_sample_spec *spec,
     const pa_cvolume *volume);
 
+typedef struct pa_volume_ramp_int_t {
+    pa_volume_ramp_type_t type;
+    long length;
+    long left;
+    float start;
+    float end;
+    float curr;
+    pa_volume_t target;
+} pa_volume_ramp_int_t;
+
+typedef struct pa_cvolume_ramp_int {
+    uint8_t channels;
+    pa_volume_ramp_int_t ramps[PA_CHANNELS_MAX];
+} pa_cvolume_ramp_int;
+
+pa_cvolume_ramp_int* pa_cvolume_ramp_convert(const pa_cvolume_ramp *src, pa_cvolume_ramp_int *dst, int sample_rate);
+bool pa_cvolume_ramp_active(pa_cvolume_ramp_int *ramp);
+bool pa_cvolume_ramp_target_active(pa_cvolume_ramp_int *ramp);
+pa_cvolume_ramp_int* pa_cvolume_ramp_start_from(pa_cvolume_ramp_int *src, pa_cvolume_ramp_int *dst);
+pa_cvolume_ramp_int* pa_cvolume_ramp_int_init(pa_cvolume_ramp_int *src, pa_volume_t vol, int channels);
+pa_cvolume * pa_cvolume_ramp_get_targets(pa_cvolume_ramp_int *ramp, pa_cvolume *volume);
+
+void pa_volume_ramp_memchunk(
+        pa_memchunk *c,
+        const pa_sample_spec *spec,
+        pa_cvolume_ramp_int *ramp);
+
 #endif