Commit 69fc8e9f authored by Stefan Sauer's avatar Stefan Sauer

audiomix: add a simple audiomix example

parent f35c51c1
......@@ -5,3 +5,9 @@ testchannels_CFLAGS = $(GST_PLUGINS_BASE_CFLAGS) $(GST_CFLAGS)
testchannels_LDADD = $(top_builddir)/gst-libs/gst/audio/libgstaudio-$(GST_MAJORMINOR).la \
$(GST_LIBS)
if HAVE_GTK
noinst_PROGRAMS = audiomix
audiomix_SOURCES = audiomix.c
audiomix_CFLAGS = $(GST_CFLAGS) $(GTK_CFLAGS) -D_GNU_SOURCE
audiomix_LDADD = $(GST_LIBS) $(GTK_LIBS) $(LIBM)
endif
/* GStreamer
*
* audiomix.c: sample audio mixing application
*
* Copyright (C) 2011 Stefan Sauer <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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include <gst/gst.h>
#include <gtk/gtk.h>
/* global items for the interaction */
static GtkWidget *scale;
static GObject *volumes[2];
static gint num_vol = 0;
static void
value_changed_callback (GtkWidget * widget, gpointer * user_data)
{
gdouble value = gtk_range_get_value (GTK_RANGE (widget));
g_object_set (volumes[0], "volume", 1.0 - value, NULL);
g_object_set (volumes[1], "volume", value, NULL);
}
static void
setup_gui (GstElement * volume, gchar * file_name1, gchar * file_name2)
{
GtkWidget *window, *layout, *label;
gchar *name, *ext;
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW (window), "audiomix");
g_signal_connect (window, "destroy", gtk_main_quit, NULL);
layout = gtk_table_new (2, 3, FALSE);
gtk_table_set_col_spacings (GTK_TABLE (layout), 6);
gtk_container_add (GTK_CONTAINER (window), layout);
/* channel labels */
name = g_path_get_basename (file_name1);
if ((ext = strrchr (name, '.')))
*ext = '\0';
label = gtk_label_new (name);
g_free (name);
gtk_misc_set_alignment (GTK_MISC (label), 0.0, 0.5);
gtk_table_attach_defaults (GTK_TABLE (layout), label, 0, 1, 0, 1);
gtk_table_attach_defaults (GTK_TABLE (layout), gtk_label_new ("|"), 1, 2, 0,
1);
name = g_path_get_basename (file_name2);
if ((ext = strrchr (name, '.')))
*ext = '\0';
label = gtk_label_new (name);
g_free (name);
gtk_misc_set_alignment (GTK_MISC (label), 1.0, 0.5);
gtk_table_attach_defaults (GTK_TABLE (layout), label, 2, 3, 0, 1);
/* mix slider */
scale = gtk_hscale_new_with_range (0.0, 1.0, 1.0 / 200.0);
gtk_range_set_value (GTK_RANGE (scale), 0.0);
gtk_widget_set_size_request (scale, 200, -1);
gtk_table_attach_defaults (GTK_TABLE (layout), scale, 0, 3, 1, 2);
g_signal_connect (scale, "value-changed",
G_CALLBACK (value_changed_callback), volume);
gtk_widget_show_all (GTK_WIDGET (window));
}
static void
message_received (GstBus * bus, GstMessage * message, GstPipeline * pipeline)
{
const GstStructure *s;
s = gst_message_get_structure (message);
g_print ("message from \"%s\" (%s): ",
GST_STR_NULL (GST_ELEMENT_NAME (GST_MESSAGE_SRC (message))),
gst_message_type_get_name (GST_MESSAGE_TYPE (message)));
if (s) {
gchar *sstr;
sstr = gst_structure_to_string (s);
g_print ("%s\n", sstr);
g_free (sstr);
} else {
g_print ("no message details\n");
}
}
static void
eos_message_received (GstBus * bus, GstMessage * message,
GstPipeline * pipeline)
{
message_received (bus, message, pipeline);
gtk_main_quit ();
}
static void
dynamic_link (GstPadTemplate * templ, GstPad * newpad, gpointer user_data)
{
GstPad *target = GST_PAD (user_data);
gst_pad_link (newpad, target);
gst_object_unref (target);
}
static void
make_mixer_channel (GstElement * pipeline, GstElement * mix, gchar * file_name)
{
GstElement *filesrc, *decodebin, *volume, *convert, *format;
GstCaps *caps;
/* prepare mixer channel */
filesrc = gst_element_factory_make ("filesrc", NULL);
decodebin = gst_element_factory_make ("decodebin2", NULL);
volume = gst_element_factory_make ("volume", NULL);
convert = gst_element_factory_make ("audioconvert", NULL);
format = gst_element_factory_make ("capsfilter", NULL);
gst_bin_add_many (GST_BIN (pipeline), filesrc, decodebin, volume, convert,
format, NULL);
gst_element_link (filesrc, decodebin);
gst_element_link_many (volume, convert, format, mix, NULL);
/* configure elements */
g_object_set (filesrc, "location", file_name, NULL);
g_object_set (volume, "volume", (num_vol == 0) ? 1.0 : 0.0, NULL);
caps = gst_caps_from_string ("audio/x-raw-int, "
"channels = (int) 2, "
"endianness = (int) BYTE_ORDER, "
"width = (int) 16, " "depth = (int) 16, " "signed = (boolean) true");
g_object_set (format, "caps", caps, NULL);
gst_caps_unref (caps);
/* remember volume element */
volumes[num_vol++] = (GObject *) volume;
/* handle dynamic pads */
g_signal_connect (G_OBJECT (decodebin), "pad-added",
G_CALLBACK (dynamic_link), gst_element_get_static_pad (volume, "sink"));
}
int
main (int argc, char *argv[])
{
GstElement *pipeline = NULL;
GstElement *mix, *convert, *sink;
GstBus *bus;
if (argc < 3) {
g_print ("Usage: audiomix <file1> <file2>\n");
return 1;
}
gst_init (&argc, &argv);
gtk_init (&argc, &argv);
/* prepare tail of pipeline */
pipeline = gst_pipeline_new ("audiomix");
mix = gst_element_factory_make ("adder", NULL);
convert = gst_element_factory_make ("audioconvert", NULL);
sink = gst_element_factory_make ("autoaudiosink", NULL);
gst_bin_add_many (GST_BIN (pipeline), mix, convert, sink, NULL);
gst_element_link_many (mix, convert, sink, NULL);
/* prepare mixer channel strips */
make_mixer_channel (pipeline, mix, argv[1]);
make_mixer_channel (pipeline, mix, argv[2]);
/* setup message handling */
bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));
gst_bus_add_signal_watch_full (bus, G_PRIORITY_HIGH);
g_signal_connect (bus, "message::error", (GCallback) message_received,
pipeline);
g_signal_connect (bus, "message::warning", (GCallback) message_received,
pipeline);
g_signal_connect (bus, "message::eos", (GCallback) eos_message_received,
pipeline);
/* setup GUI */
setup_gui (pipeline, argv[1], argv[2]);
/* go to main loop */
gst_element_set_state (pipeline, GST_STATE_PLAYING);
gtk_main ();
gst_element_set_state (pipeline, GST_STATE_NULL);
gst_object_unref (pipeline);
return 0;
}
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