fluidsynth: add fluidsynth midi renderer

Add a fluidsynth element that converts midi events into raw
float samples.

3 files changed, 559 insertions, 0 deletions

diff --git a/ext/fluidsynth/Makefile.am b/ext/fluidsynth/Makefile.am
new file mode 100644
index 000000000..233c0bd61
--- /dev/null
+++ b/ext/fluidsynth/Makefile.am
@@ -0,0 +1,20 @@
+# plugindir is set in configure
+plugin_LTLIBRARIES =
+
+if USE_FLUIDSYNTH
+plugin_LTLIBRARIES += libgstfluidsynth.la
+
+# sources used to compile this plug-in
+libgstfluidsynth_la_SOURCES = gstfluidsynth.c
+
+# flags used to compile this plugin
+# add other _CFLAGS and _LIBS as needed
+libgstfluidsynth_la_CFLAGS = $(GST_PLUGINS_BASE_CFLAGS) $(GST_CFLAGS) \
+			     $(GST_BASE_CFLAGS) $(FLUIDSYNTH_CFLAGS)
+libgstfluidsynth_la_LIBADD = $(GST_LIBS) $(GST_BASE_LIBS) $(FLUIDSYNTH_LIBS)
+libgstfluidsynth_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS)
+libgstfluidsynth_la_LIBTOOLFLAGS = --tag=disable-static
+endif
+
+noinst_HEADERS = gstfluidsynth.h
+
diff --git a/ext/fluidsynth/gstfluidsynth.c b/ext/fluidsynth/gstfluidsynth.c
new file mode 100644
index 000000000..d52b3319f
--- /dev/null
+++ b/ext/fluidsynth/gstfluidsynth.c
@@ -0,0 +1,471 @@
+/*
+ * gstfluidsynth - fluidsynth plugin for gstreamer
+ *
+ * Copyright 2013 Wim Taymans <wim.taymans@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+/**
+ * SECTION:element-fluidsynth
+ * @see_also: timidity, wildmidi
+ *
+ * This element renders midi-events as audio streams using
+ * <ulink url="http://fluidsynth.sourceforge.net//">Fluidsynth</ulink>.
+ * It offers better sound quality compared to the timidity or wildmidi element.
+ *
+ * <refsect2>
+ * <title>Example pipeline</title>
+ * |[
+ * gst-launch-1.0 filesrc location=song.mid ! midiparse ! fluidsynth ! pulsesink
+ * ]| This example pipeline will parse the midi and render to raw audio which is
+ * played via pulseaudio.
+ * </refsect2>
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+#define FLUIDSYNTH_RATE 44100
+#define FLUIDSYNTH_BPS  (4 * 2)
+
+#include <gst/gst.h>
+#include <string.h>
+#include <glib.h>
+#include <glib/gstdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <gst/audio/audio.h>
+
+#include "gstfluidsynth.h"
+
+GST_DEBUG_CATEGORY_STATIC (gst_fluidsynth_debug);
+#define GST_CAT_DEFAULT gst_fluidsynth_debug
+
+enum
+{
+  /* FILL ME */
+  LAST_SIGNAL
+};
+
+enum
+{
+  PROP_0,
+  /* FILL ME */
+};
+
+static void gst_fluidsynth_finalize (GObject * object);
+
+static gboolean gst_fluidsynth_sink_event (GstPad * pad, GstObject * parent,
+    GstEvent * event);
+
+static GstStateChangeReturn gst_fluidsynth_change_state (GstElement * element,
+    GstStateChange transition);
+
+static GstFlowReturn gst_fluidsynth_chain (GstPad * sinkpad, GstObject * parent,
+    GstBuffer * buffer);
+
+static void gst_fluidsynth_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec);
+static void gst_fluidsynth_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec);
+
+static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
+    GST_PAD_SINK,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS ("audio/x-midi-event")
+    );
+
+static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src",
+    GST_PAD_SRC,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS ("audio/x-raw, "
+        "format = (string) " GST_AUDIO_NE (F32) ", "
+        "rate = (int) " G_STRINGIFY (FLUIDSYNTH_RATE) ", "
+        "channels = (int) 2, " "layout = (string) interleaved"));
+
+#define parent_class gst_fluidsynth_parent_class
+G_DEFINE_TYPE (GstFluidsynth, gst_fluidsynth, GST_TYPE_ELEMENT);
+
+/* initialize the plugin's class */
+static void
+gst_fluidsynth_class_init (GstFluidsynthClass * klass)
+{
+  GObjectClass *gobject_class;
+  GstElementClass *gstelement_class;
+
+  gobject_class = (GObjectClass *) klass;
+  gstelement_class = (GstElementClass *) klass;
+
+  gobject_class->finalize = gst_fluidsynth_finalize;
+  gobject_class->set_property = gst_fluidsynth_set_property;
+  gobject_class->get_property = gst_fluidsynth_get_property;
+
+  gst_element_class_add_pad_template (gstelement_class,
+      gst_static_pad_template_get (&src_factory));
+  gst_element_class_add_pad_template (gstelement_class,
+      gst_static_pad_template_get (&sink_factory));
+
+  gst_element_class_set_static_metadata (gstelement_class, "Fluidsynth",
+      "Codec/Decoder/Audio",
+      "Midi Synthesizer Element", "Wim Taymans <wim.taymans@gmail.com>");
+
+  gstelement_class->change_state = gst_fluidsynth_change_state;
+}
+
+/* initialize the new element
+ * instantiate pads and add them to element
+ * set functions
+ * initialize structure
+ */
+static void
+gst_fluidsynth_init (GstFluidsynth * filter)
+{
+  filter->sinkpad = gst_pad_new_from_static_template (&sink_factory, "sink");
+  gst_pad_set_event_function (filter->sinkpad, gst_fluidsynth_sink_event);
+  gst_pad_set_chain_function (filter->sinkpad, gst_fluidsynth_chain);
+  gst_element_add_pad (GST_ELEMENT (filter), filter->sinkpad);
+
+  filter->srcpad = gst_pad_new_from_static_template (&src_factory, "src");
+  gst_pad_use_fixed_caps (filter->srcpad);
+  gst_element_add_pad (GST_ELEMENT (filter), filter->srcpad);
+}
+
+static void
+gst_fluidsynth_finalize (GObject * object)
+{
+  G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
+#if 0
+static GstBuffer *
+gst_fluidsynth_clip_buffer (GstFluidsynth * fluidsynth, GstBuffer * buffer)
+{
+  guint64 start, stop;
+  guint64 new_start, new_stop;
+  gint64 offset, length;
+
+  /* clipping disabled for now */
+  return buffer;
+
+  start = GST_BUFFER_OFFSET (buffer);
+  stop = GST_BUFFER_OFFSET_END (buffer);
+
+  if (!gst_segment_clip (&fluidsynth->segment, GST_FORMAT_DEFAULT,
+          start, stop, &new_start, &new_stop)) {
+    gst_buffer_unref (buffer);
+    return NULL;
+  }
+
+  if (start == new_start && stop == new_stop)
+    return buffer;
+
+  offset = new_start - start;
+  length = new_stop - new_start;
+
+  buffer = gst_buffer_make_writable (buffer);
+  gst_buffer_resize (buffer, offset, length);
+
+  GST_BUFFER_OFFSET (buffer) = new_start;
+  GST_BUFFER_OFFSET_END (buffer) = new_stop;
+  GST_BUFFER_TIMESTAMP (buffer) =
+      gst_util_uint64_scale_int (new_start, GST_SECOND, FLUIDSYNTH_RATE);
+  GST_BUFFER_DURATION (buffer) =
+      gst_util_uint64_scale_int (new_stop, GST_SECOND, FLUIDSYNTH_RATE) -
+      GST_BUFFER_TIMESTAMP (buffer);
+
+  return buffer;
+}
+#endif
+
+static gboolean
+gst_fluidsynth_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
+{
+  gboolean res;
+  GstFluidsynth *fluidsynth = GST_FLUIDSYNTH (parent);
+
+  GST_DEBUG_OBJECT (pad, "%s event received", GST_EVENT_TYPE_NAME (event));
+
+  switch (GST_EVENT_TYPE (event)) {
+    case GST_EVENT_CAPS:
+    {
+      GstCaps *caps;
+
+      caps = gst_caps_new_simple ("audio/x-raw",
+          "format", G_TYPE_STRING, GST_AUDIO_NE (F32),
+          "rate", G_TYPE_INT, FLUIDSYNTH_RATE,
+          "channels", G_TYPE_INT, 2,
+          "layout", G_TYPE_STRING, "interleaved", NULL);
+
+      res = gst_pad_push_event (fluidsynth->srcpad, gst_event_new_caps (caps));
+      gst_caps_unref (caps);
+      break;
+    }
+    case GST_EVENT_SEGMENT:
+      gst_event_copy_segment (event, &fluidsynth->segment);
+      GST_DEBUG_OBJECT (fluidsynth, "configured segment %" GST_SEGMENT_FORMAT,
+          fluidsynth->segment);
+      res = gst_pad_event_default (pad, parent, event);
+      break;
+    case GST_EVENT_EOS:
+      /* FIXME, push last samples */
+      res = gst_pad_event_default (pad, parent, event);
+      break;
+    default:
+      res = gst_pad_event_default (pad, parent, event);
+      break;
+  }
+  return res;
+}
+
+static GstFlowReturn
+produce_samples (GstFluidsynth * fluidsynth, GstClockTime pts)
+{
+  GstClockTime out_duration;
+  guint samples;
+  GstMapInfo info;
+  GstBuffer *outbuf;
+
+  out_duration = pts - fluidsynth->last_pts;
+
+  samples =
+      gst_util_uint64_scale_int (out_duration, FLUIDSYNTH_RATE, GST_SECOND);
+
+  GST_DEBUG_OBJECT (fluidsynth,
+      "duration %" GST_TIME_FORMAT ", samples %u",
+      GST_TIME_ARGS (out_duration), samples);
+
+  outbuf = gst_buffer_new_allocate (NULL, samples * FLUIDSYNTH_BPS, NULL);
+
+  gst_buffer_map (outbuf, &info, GST_MAP_WRITE);
+  fluid_synth_write_float (fluidsynth->synth, samples, info.data, 0, 2,
+      info.data, 1, 2);
+  gst_buffer_unmap (outbuf, &info);
+
+  GST_BUFFER_DTS (outbuf) = fluidsynth->last_pts;
+  GST_BUFFER_PTS (outbuf) = fluidsynth->last_pts;
+  GST_BUFFER_DURATION (outbuf) = out_duration;
+
+  return gst_pad_push (fluidsynth->srcpad, outbuf);
+}
+
+static void
+handle_buffer (GstFluidsynth * fluidsynth, GstBuffer * buffer)
+{
+  GstMapInfo info;
+  guint8 event, channel;
+
+  gst_buffer_map (buffer, &info, GST_MAP_READ);
+
+  event = info.data[0];
+  channel = event & 0x0f;
+
+  switch (event & 0xf0) {
+    case 0xf0:
+      switch (event) {
+        case 0xff:
+          fluid_synth_system_reset (fluidsynth->synth);
+          break;
+        case 0xf0:
+        case 0xf7:
+          fluid_synth_sysex (fluidsynth->synth, (char *) info.data + 1,
+              info.size - 1, NULL, NULL, NULL, 0);
+
+          break;
+        default:
+          GST_WARNING_OBJECT (fluidsynth, "unhandled event 0x%02x", event);
+          break;
+      }
+      break;
+    default:
+    {
+      guint8 p1, p2;
+
+      p1 = info.size > 1 ? info.data[1] & 0x7f : 0;
+      p2 = info.size > 2 ? info.data[2] & 0x7f : 0;
+
+      switch (event & 0xf0) {
+        case 0x80:
+          fluid_synth_noteoff (fluidsynth->synth, channel, p1);
+          break;
+        case 0x90:
+          fluid_synth_noteon (fluidsynth->synth, channel, p1, p2);
+          break;
+        case 0xA0:
+          /* aftertouch */
+          break;
+        case 0xB0:
+          fluid_synth_cc (fluidsynth->synth, channel, p1, p2);
+          break;
+        case 0xC0:
+          fluid_synth_program_change (fluidsynth->synth, channel, p1);
+          break;
+        case 0xD0:
+          fluid_synth_channel_pressure (fluidsynth->synth, channel, p1);
+          break;
+        case 0xE0:
+          fluid_synth_pitch_bend (fluidsynth->synth, channel, (p2 << 7) | p1);
+          break;
+        default:
+          break;
+      }
+      break;
+    }
+  }
+  gst_buffer_unmap (buffer, &info);
+}
+
+static GstFlowReturn
+gst_fluidsynth_chain (GstPad * sinkpad, GstObject * parent, GstBuffer * buffer)
+{
+  GstFlowReturn res = GST_FLOW_OK;
+  GstFluidsynth *fluidsynth;
+  GstClockTime pts;
+
+  fluidsynth = GST_FLUIDSYNTH (parent);
+
+  pts = GST_BUFFER_PTS (buffer);
+
+  if (fluidsynth->last_pts == GST_CLOCK_TIME_NONE) {
+    fluidsynth->last_pts = pts;
+  } else if (pts != GST_CLOCK_TIME_NONE && fluidsynth->last_pts < pts) {
+    /* generate samples for the elapsed time */
+    res = produce_samples (fluidsynth, pts);
+  }
+
+  if (res == GST_FLOW_OK) {
+    handle_buffer (fluidsynth, buffer);
+
+    fluidsynth->last_pts = pts;
+  }
+  gst_buffer_unref (buffer);
+
+  return res;
+}
+
+static gboolean
+gst_fluidsynth_open (GstFluidsynth * fluidsynth)
+{
+  if (fluidsynth->settings == NULL) {
+    fluidsynth->settings = new_fluid_settings ();
+    fluidsynth->synth = new_fluid_synth (fluidsynth->settings);
+    /* FIXME configure path */
+    fluidsynth->soundfont = fluid_synth_sfload (fluidsynth->synth,
+        "/usr/share/sounds/sf2/FluidR3_GM.sf2", 1);
+    fluid_synth_set_chorus_on (fluidsynth->synth, TRUE);
+    fluid_synth_set_gain (fluidsynth->synth, 0.2);
+    fluid_synth_set_polyphony (fluidsynth->synth, 256);
+    fluid_synth_set_reverb_on (fluidsynth->synth, TRUE);
+    fluid_synth_set_sample_rate (fluidsynth->synth, FLUIDSYNTH_RATE);
+  }
+
+  return TRUE;
+}
+
+static gboolean
+gst_fluidsynth_close (GstFluidsynth * fluidsynth)
+{
+  if (fluidsynth->settings) {
+    fluid_synth_sfunload (fluidsynth->synth, fluidsynth->soundfont, 1);
+    delete_fluid_synth (fluidsynth->synth);
+    delete_fluid_settings (fluidsynth->settings);
+    fluidsynth->settings = NULL;
+  }
+  return TRUE;
+}
+
+static GstStateChangeReturn
+gst_fluidsynth_change_state (GstElement * element, GstStateChange transition)
+{
+  GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
+  GstFluidsynth *fluidsynth = GST_FLUIDSYNTH (element);
+
+  switch (transition) {
+    case GST_STATE_CHANGE_NULL_TO_READY:
+      if (!gst_fluidsynth_open (fluidsynth))
+        goto open_failed;
+      break;
+    case GST_STATE_CHANGE_READY_TO_PAUSED:
+      break;
+    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
+      break;
+    default:
+      break;
+  }
+
+  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
+
+  switch (transition) {
+    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
+      break;
+    case GST_STATE_CHANGE_PAUSED_TO_READY:
+      break;
+    case GST_STATE_CHANGE_READY_TO_NULL:
+      gst_fluidsynth_close (fluidsynth);
+      break;
+    default:
+      break;
+  }
+
+  return ret;
+
+  /* ERRORS */
+open_failed:
+  {
+    GST_ERROR_OBJECT (fluidsynth, "could not open");
+    return GST_STATE_CHANGE_FAILURE;
+  }
+}
+
+static void
+gst_fluidsynth_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  switch (prop_id) {
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_fluidsynth_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec)
+{
+  switch (prop_id) {
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static gboolean
+plugin_init (GstPlugin * plugin)
+{
+  GST_DEBUG_CATEGORY_INIT (gst_fluidsynth_debug, "fluidsynth",
+      0, "Fluidsynth plugin");
+
+  return gst_element_register (plugin, "fluidsynth",
+      GST_RANK_SECONDARY, GST_TYPE_FLUIDSYNTH);
+}
+
+GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
+    GST_VERSION_MINOR,
+    fluidsynth,
+    "Fluidsynth Plugin",
+    plugin_init, VERSION, "LGPL", GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)
diff --git a/ext/fluidsynth/gstfluidsynth.h b/ext/fluidsynth/gstfluidsynth.h
new file mode 100644
index 000000000..0fcb7babe
--- /dev/null
+++ b/ext/fluidsynth/gstfluidsynth.h
@@ -0,0 +1,68 @@
+/*
+ * gstfluidsynth - fluidsynth plugin for gstreamer
+ *
+ * Copyright 2007 Wouter Paesen <wouter@blue-gate.be>
+ * Copyright 2013 Wim Taymans <wim.taymans@gmail.be>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __GST_FLUIDSYNTH_H__
+#define __GST_FLUIDSYNTH_H__
+
+#include <gst/gst.h>
+#include <gst/base/gstadapter.h>
+#include <fluidsynth.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_FLUIDSYNTH \
+  (gst_fluidsynth_get_type())
+#define GST_FLUIDSYNTH(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_FLUIDSYNTH,GstFluidsynth))
+#define GST_FLUIDSYNTH_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_FLUIDSYNTH,GstFluidsynthClass))
+#define GST_IS_FLUIDSYNTH(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_FLUIDSYNTH))
+#define GST_IS_FLUIDSYNTH_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_FLUIDSYNTH))
+
+typedef struct _GstFluidsynth GstFluidsynth;
+typedef struct _GstFluidsynthClass GstFluidsynthClass;
+
+struct _GstFluidsynth
+{
+  GstElement element;
+
+  GstPad *sinkpad, *srcpad;
+  GstSegment segment;
+  GstClockTime last_pts;
+
+  fluid_settings_t* settings;
+  fluid_synth_t* synth;
+  int soundfont;
+};
+
+struct _GstFluidsynthClass
+{
+    GstElementClass parent_class;
+};
+
+GType gst_fluidsynth_get_type (void);
+
+G_END_DECLS
+
+#endif /* __GST_FLUIDSYNTH_H__ */