gst_plugins_good/gst/audiofx/audioinvert.c
changeset 8 4a7fac7dd34a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gst_plugins_good/gst/audiofx/audioinvert.c	Fri Apr 16 15:15:52 2010 +0300
@@ -0,0 +1,252 @@
+/* 
+ * GStreamer
+ * Copyright (C) 2007 Sebastian Dröge <slomo@circular-chaos.org>
+ * Copyright (C) 2006 Stefan Kost <ensonic@users.sf.net>
+ *
+ * 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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * SECTION:element-audioinvert
+ *
+ * Swaps upper and lower half of audio samples. Mixing an inverted sample on top of
+ * the original with a slight delay can produce effects that sound like resonance.
+ * Creating a stereo sample from a mono source, with one channel inverted produces wide-stereo sounds.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch audiotestsrc wave=saw ! audioinvert invert=0.4 ! alsasink
+ * gst-launch filesrc location="melo1.ogg" ! oggdemux ! vorbisdec ! audioconvert ! audioinvert invert=0.4 ! alsasink
+ * gst-launch audiotestsrc wave=saw ! audioconvert ! audioinvert invert=0.4 ! audioconvert ! alsasink
+ * ]|
+ * </refsect2>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/gst.h>
+#include <gst/base/gstbasetransform.h>
+#include <gst/audio/audio.h>
+#include <gst/audio/gstaudiofilter.h>
+#include <gst/controller/gstcontroller.h>
+
+#include "audioinvert.h"
+
+#define GST_CAT_DEFAULT gst_audio_invert_debug
+GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
+
+static const GstElementDetails element_details =
+GST_ELEMENT_DETAILS ("Audio inversion",
+    "Filter/Effect/Audio",
+    "Swaps upper and lower half of audio samples",
+    "Sebastian Dröge <slomo@circular-chaos.org>");
+
+/* Filter signals and args */
+enum
+{
+  /* FILL ME */
+  LAST_SIGNAL
+};
+
+enum
+{
+  PROP_0,
+  PROP_DEGREE
+};
+
+#define ALLOWED_CAPS \
+    "audio/x-raw-int,"                                                \
+    " depth=(int)16,"                                                 \
+    " width=(int)16,"                                                 \
+    " endianness=(int)BYTE_ORDER,"                                    \
+    " signed=(bool)TRUE,"                                             \
+    " rate=(int)[1,MAX],"                                             \
+    " channels=(int)[1,MAX]; "                                        \
+    "audio/x-raw-float,"                                              \
+    " width=(int)32,"                                                 \
+    " endianness=(int)BYTE_ORDER,"                                    \
+    " rate=(int)[1,MAX],"                                             \
+    " channels=(int)[1,MAX]"
+
+#define DEBUG_INIT(bla) \
+  GST_DEBUG_CATEGORY_INIT (gst_audio_invert_debug, "audioinvert", 0, "audioinvert element");
+
+GST_BOILERPLATE_FULL (GstAudioInvert, gst_audio_invert, GstAudioFilter,
+    GST_TYPE_AUDIO_FILTER, DEBUG_INIT);
+
+static void gst_audio_invert_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec);
+static void gst_audio_invert_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec);
+
+static gboolean gst_audio_invert_setup (GstAudioFilter * filter,
+    GstRingBufferSpec * format);
+static GstFlowReturn gst_audio_invert_transform_ip (GstBaseTransform * base,
+    GstBuffer * buf);
+
+static void gst_audio_invert_transform_int (GstAudioInvert * filter,
+    gint16 * data, guint num_samples);
+static void gst_audio_invert_transform_float (GstAudioInvert * filter,
+    gfloat * data, guint num_samples);
+
+/* GObject vmethod implementations */
+
+static void
+gst_audio_invert_base_init (gpointer klass)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
+  GstCaps *caps;
+
+  gst_element_class_set_details (element_class, &element_details);
+
+  caps = gst_caps_from_string (ALLOWED_CAPS);
+  gst_audio_filter_class_add_pad_templates (GST_AUDIO_FILTER_CLASS (klass),
+      caps);
+  gst_caps_unref (caps);
+}
+
+static void
+gst_audio_invert_class_init (GstAudioInvertClass * klass)
+{
+  GObjectClass *gobject_class;
+
+  gobject_class = (GObjectClass *) klass;
+  gobject_class->set_property = gst_audio_invert_set_property;
+  gobject_class->get_property = gst_audio_invert_get_property;
+
+  g_object_class_install_property (gobject_class, PROP_DEGREE,
+      g_param_spec_float ("degree", "Degree",
+          "Degree of inversion", 0.0, 1.0,
+          0.0, G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE));
+
+  GST_AUDIO_FILTER_CLASS (klass)->setup =
+      GST_DEBUG_FUNCPTR (gst_audio_invert_setup);
+  GST_BASE_TRANSFORM_CLASS (klass)->transform_ip =
+      GST_DEBUG_FUNCPTR (gst_audio_invert_transform_ip);
+}
+
+static void
+gst_audio_invert_init (GstAudioInvert * filter, GstAudioInvertClass * klass)
+{
+  filter->degree = 0.0;
+  gst_base_transform_set_in_place (GST_BASE_TRANSFORM (filter), TRUE);
+  gst_base_transform_set_gap_aware (GST_BASE_TRANSFORM (filter), TRUE);
+}
+
+static void
+gst_audio_invert_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  GstAudioInvert *filter = GST_AUDIO_INVERT (object);
+
+  switch (prop_id) {
+    case PROP_DEGREE:
+      filter->degree = g_value_get_float (value);
+      gst_base_transform_set_passthrough (GST_BASE_TRANSFORM (filter),
+          filter->degree == 0.0);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static void
+gst_audio_invert_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec)
+{
+  GstAudioInvert *filter = GST_AUDIO_INVERT (object);
+
+  switch (prop_id) {
+    case PROP_DEGREE:
+      g_value_set_float (value, filter->degree);
+      break;
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+/* GstAudioFilter vmethod implementations */
+
+static gboolean
+gst_audio_invert_setup (GstAudioFilter * base, GstRingBufferSpec * format)
+{
+  GstAudioInvert *filter = GST_AUDIO_INVERT (base);
+  gboolean ret = TRUE;
+
+  if (format->type == GST_BUFTYPE_FLOAT && format->width == 32)
+    filter->process = (GstAudioInvertProcessFunc)
+        gst_audio_invert_transform_float;
+  else if (format->type == GST_BUFTYPE_LINEAR && format->width == 16)
+    filter->process = (GstAudioInvertProcessFunc)
+        gst_audio_invert_transform_int;
+  else
+    ret = FALSE;
+
+  return ret;
+}
+
+static void
+gst_audio_invert_transform_int (GstAudioInvert * filter,
+    gint16 * data, guint num_samples)
+{
+  gint i;
+  gfloat dry = 1.0 - filter->degree;
+  glong val;
+
+  for (i = 0; i < num_samples; i++) {
+    val = (*data) * dry + (-1 - (*data)) * filter->degree;
+    *data++ = (gint16) CLAMP (val, G_MININT16, G_MAXINT16);
+  }
+}
+
+static void
+gst_audio_invert_transform_float (GstAudioInvert * filter,
+    gfloat * data, guint num_samples)
+{
+  gint i;
+  gfloat dry = 1.0 - filter->degree;
+  glong val;
+
+  for (i = 0; i < num_samples; i++) {
+    val = (*data) * dry - (*data) * filter->degree;
+    *data++ = val;
+  }
+}
+
+/* GstBaseTransform vmethod implementations */
+static GstFlowReturn
+gst_audio_invert_transform_ip (GstBaseTransform * base, GstBuffer * buf)
+{
+  GstAudioInvert *filter = GST_AUDIO_INVERT (base);
+  guint num_samples =
+      GST_BUFFER_SIZE (buf) / (GST_AUDIO_FILTER (filter)->format.width / 8);
+
+  if (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_TIMESTAMP (buf)))
+    gst_object_sync_values (G_OBJECT (filter), GST_BUFFER_TIMESTAMP (buf));
+
+  if (gst_base_transform_is_passthrough (base) ||
+      G_UNLIKELY (GST_BUFFER_FLAG_IS_SET (buf, GST_BUFFER_FLAG_GAP)))
+    return GST_FLOW_OK;
+
+  filter->process (filter, GST_BUFFER_DATA (buf), num_samples);
+
+  return GST_FLOW_OK;
+}