--- /dev/null
+/* GStreamer
+ * Copyright (C) 2013 David Schleef <ds@schleef.org>
+ *
+ * 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 Street, Suite 500,
+ * Boston, MA 02110-1335, USA.
+ */
+/**
+ * SECTION:element-gstaudiochannelmix
+ *
+ * The audiochannelmix element mixes channels in stereo audio based on
+ * properties set on the element. The primary purpose is reconstruct
+ * equal left/right channels on an input stream that has audio in only
+ * one channel.
+ *
+ * <refsect2>
+ * <title>Example launch line</title>
+ * |[
+ * gst-launch -v audiotestsrc ! audiochannelmix ! autoaudiosink
+ * ]|
+ * </refsect2>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/gst.h>
+#include <gst/audio/gstaudiofilter.h>
+#include "gstaudiochannelmix.h"
+#include <math.h>
+
+GST_DEBUG_CATEGORY_STATIC (gst_audio_channel_mix_debug_category);
+#define GST_CAT_DEFAULT gst_audio_channel_mix_debug_category
+
+/* prototypes */
+
+
+static void gst_audio_channel_mix_set_property (GObject * object,
+ guint property_id, const GValue * value, GParamSpec * pspec);
+static void gst_audio_channel_mix_get_property (GObject * object,
+ guint property_id, GValue * value, GParamSpec * pspec);
+static void gst_audio_channel_mix_dispose (GObject * object);
+static void gst_audio_channel_mix_finalize (GObject * object);
+
+static gboolean gst_audio_channel_mix_setup (GstAudioFilter * filter,
+ const GstAudioInfo * info);
+static GstFlowReturn gst_audio_channel_mix_transform_ip (GstBaseTransform *
+ trans, GstBuffer * buf);
+
+enum
+{
+ PROP_0,
+ PROP_LEFT_TO_LEFT,
+ PROP_LEFT_TO_RIGHT,
+ PROP_RIGHT_TO_LEFT,
+ PROP_RIGHT_TO_RIGHT
+};
+
+/* pad templates */
+
+static GstStaticPadTemplate gst_audio_channel_mix_src_template =
+GST_STATIC_PAD_TEMPLATE ("src",
+ GST_PAD_SRC,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("audio/x-raw,format=S16LE,rate=[1,max],"
+ "channels=2,layout=interleaved")
+ );
+
+static GstStaticPadTemplate gst_audio_channel_mix_sink_template =
+GST_STATIC_PAD_TEMPLATE ("sink",
+ GST_PAD_SINK,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("audio/x-raw,format=S16LE,rate=[1,max],"
+ "channels=2,layout=interleaved")
+ );
+
+
+/* class initialization */
+
+G_DEFINE_TYPE_WITH_CODE (GstAudioChannelMix, gst_audio_channel_mix,
+ GST_TYPE_AUDIO_FILTER,
+ GST_DEBUG_CATEGORY_INIT (gst_audio_channel_mix_debug_category,
+ "audiochannelmix", 0, "debug category for audiochannelmix element"));
+
+static void
+gst_audio_channel_mix_class_init (GstAudioChannelMixClass * klass)
+{
+ GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
+ GstBaseTransformClass *base_transform_class =
+ GST_BASE_TRANSFORM_CLASS (klass);
+ GstAudioFilterClass *audio_filter_class = GST_AUDIO_FILTER_CLASS (klass);
+
+ /* Setting up pads and setting metadata should be moved to
+ base_class_init if you intend to subclass this class. */
+ gst_element_class_add_pad_template (GST_ELEMENT_CLASS (klass),
+ gst_static_pad_template_get (&gst_audio_channel_mix_src_template));
+ gst_element_class_add_pad_template (GST_ELEMENT_CLASS (klass),
+ gst_static_pad_template_get (&gst_audio_channel_mix_sink_template));
+
+ gst_element_class_set_static_metadata (GST_ELEMENT_CLASS (klass),
+ "Simple stereo audio mixer", "Audio/Mixer", "Mixes left/right channels "
+ "of stereo audio", "David Schleef <ds@schleef.org>");
+
+ gobject_class->set_property = gst_audio_channel_mix_set_property;
+ gobject_class->get_property = gst_audio_channel_mix_get_property;
+ gobject_class->dispose = gst_audio_channel_mix_dispose;
+ gobject_class->finalize = gst_audio_channel_mix_finalize;
+ audio_filter_class->setup = GST_DEBUG_FUNCPTR (gst_audio_channel_mix_setup);
+ base_transform_class->transform_ip =
+ GST_DEBUG_FUNCPTR (gst_audio_channel_mix_transform_ip);
+
+ g_object_class_install_property (gobject_class, PROP_LEFT_TO_LEFT,
+ g_param_spec_double ("left-to-left", "Left to Left",
+ "Left channel to left channel gain",
+ -G_MAXDOUBLE, G_MAXDOUBLE, 1.0,
+ GST_PARAM_CONTROLLABLE | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+ g_object_class_install_property (gobject_class, PROP_LEFT_TO_RIGHT,
+ g_param_spec_double ("left-to-right", "Left to Right",
+ "Left channel to right channel gain",
+ -G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
+ GST_PARAM_CONTROLLABLE | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+ g_object_class_install_property (gobject_class, PROP_RIGHT_TO_LEFT,
+ g_param_spec_double ("right-to-left", "Right to Left",
+ "Right channel to left channel gain",
+ -G_MAXDOUBLE, G_MAXDOUBLE, 0.0,
+ GST_PARAM_CONTROLLABLE | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+ g_object_class_install_property (gobject_class, PROP_RIGHT_TO_RIGHT,
+ g_param_spec_double ("right-to-right", "Right to Right",
+ "Right channel to right channel gain",
+ -G_MAXDOUBLE, G_MAXDOUBLE, 1.0,
+ GST_PARAM_CONTROLLABLE | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+}
+
+static void
+gst_audio_channel_mix_init (GstAudioChannelMix * audiochannelmix)
+{
+ audiochannelmix->left_to_left = 1.0;
+ audiochannelmix->left_to_right = 0.0;
+ audiochannelmix->right_to_left = 0.0;
+ audiochannelmix->right_to_right = 1.0;
+}
+
+void
+gst_audio_channel_mix_set_property (GObject * object, guint property_id,
+ const GValue * value, GParamSpec * pspec)
+{
+ GstAudioChannelMix *audiochannelmix = GST_AUDIO_CHANNEL_MIX (object);
+
+ GST_DEBUG_OBJECT (audiochannelmix, "set_property");
+
+ switch (property_id) {
+ case PROP_LEFT_TO_LEFT:
+ audiochannelmix->left_to_left = g_value_get_double (value);
+ break;
+ case PROP_LEFT_TO_RIGHT:
+ audiochannelmix->left_to_right = g_value_get_double (value);
+ break;
+ case PROP_RIGHT_TO_LEFT:
+ audiochannelmix->right_to_left = g_value_get_double (value);
+ break;
+ case PROP_RIGHT_TO_RIGHT:
+ audiochannelmix->right_to_right = g_value_get_double (value);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+ break;
+ }
+}
+
+void
+gst_audio_channel_mix_get_property (GObject * object, guint property_id,
+ GValue * value, GParamSpec * pspec)
+{
+ GstAudioChannelMix *audiochannelmix = GST_AUDIO_CHANNEL_MIX (object);
+
+ GST_DEBUG_OBJECT (audiochannelmix, "get_property");
+
+ switch (property_id) {
+ case PROP_LEFT_TO_LEFT:
+ g_value_set_double (value, audiochannelmix->left_to_left);
+ break;
+ case PROP_LEFT_TO_RIGHT:
+ g_value_set_double (value, audiochannelmix->left_to_right);
+ break;
+ case PROP_RIGHT_TO_LEFT:
+ g_value_set_double (value, audiochannelmix->right_to_left);
+ break;
+ case PROP_RIGHT_TO_RIGHT:
+ g_value_set_double (value, audiochannelmix->right_to_right);
+ break;
+ default:
+ G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
+ break;
+ }
+}
+
+void
+gst_audio_channel_mix_dispose (GObject * object)
+{
+ GstAudioChannelMix *audiochannelmix = GST_AUDIO_CHANNEL_MIX (object);
+
+ GST_DEBUG_OBJECT (audiochannelmix, "dispose");
+
+ /* clean up as possible. may be called multiple times */
+
+ G_OBJECT_CLASS (gst_audio_channel_mix_parent_class)->dispose (object);
+}
+
+void
+gst_audio_channel_mix_finalize (GObject * object)
+{
+ GstAudioChannelMix *audiochannelmix = GST_AUDIO_CHANNEL_MIX (object);
+
+ GST_DEBUG_OBJECT (audiochannelmix, "finalize");
+
+ /* clean up object here */
+
+ G_OBJECT_CLASS (gst_audio_channel_mix_parent_class)->finalize (object);
+}
+
+static gboolean
+gst_audio_channel_mix_setup (GstAudioFilter * filter, const GstAudioInfo * info)
+{
+ GstAudioChannelMix *audiochannelmix = GST_AUDIO_CHANNEL_MIX (filter);
+
+ GST_DEBUG_OBJECT (audiochannelmix, "setup");
+
+ return TRUE;
+}
+
+static GstFlowReturn
+gst_audio_channel_mix_transform_ip (GstBaseTransform * trans, GstBuffer * buf)
+{
+ GstAudioChannelMix *audiochannelmix = GST_AUDIO_CHANNEL_MIX (trans);
+ int n;
+ GstMapInfo map;
+ int i;
+ double ll = audiochannelmix->left_to_left;
+ double lr = audiochannelmix->left_to_right;
+ double rl = audiochannelmix->right_to_left;
+ double rr = audiochannelmix->right_to_right;
+ int l, r;
+ gint16 *data;
+
+ GST_DEBUG_OBJECT (audiochannelmix, "transform_ip");
+
+ gst_buffer_map (buf, &map, GST_MAP_WRITE | GST_MAP_READ);
+
+ n = gst_buffer_get_size (buf) >> 2;
+ data = (gint16 *) map.data;
+ for (i = 0; i < n; i++) {
+ l = data[2 * i + 0];
+ r = data[2 * i + 1];
+ data[2 * i + 0] = CLAMP (rint (ll * l + rl * r), -32768, 32767);
+ data[2 * i + 1] = CLAMP (rint (lr * l + rr * r), -32768, 32767);
+ }
+
+ gst_buffer_unmap (buf, &map);
+
+ return GST_FLOW_OK;
+}
projects / platform / upstream / gstreamer.git / commitdiff