1 /* GStreamer
2 *
3 * audiomix.c: sample audio mixing application
4 *
5 * Copyright (C) 2011 Stefan Sauer <ensonic@users.sf.net>
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
16 *
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
21 */
22
23 #ifdef HAVE_CONFIG_H
24 #include "config.h"
25 #endif
26
27 #include <string.h>
28 #include <gst/gst.h>
29 #include <gtk/gtk.h>
30
31 /* global items for the interaction */
32 static GtkWidget *scale;
33 static GObject *volumes[2];
34 static gint num_vol = 0;
35
36
37 static void
value_changed_callback(GtkWidget * widget,gpointer * user_data)38 value_changed_callback (GtkWidget * widget, gpointer * user_data)
39 {
40 gdouble value = gtk_range_get_value (GTK_RANGE (widget));
41 g_object_set (volumes[0], "volume", 1.0 - value, NULL);
42 g_object_set (volumes[1], "volume", value, NULL);
43 }
44
45 static void
setup_gui(GstElement * volume,gchar * file_name1,gchar * file_name2)46 setup_gui (GstElement * volume, gchar * file_name1, gchar * file_name2)
47 {
48 GtkWidget *window, *layout, *label;
49 gchar *name, *ext;
50
51 window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
52 gtk_window_set_title (GTK_WINDOW (window), "audiomix");
53 g_signal_connect (window, "destroy", gtk_main_quit, NULL);
54
55 layout = gtk_grid_new ();
56 g_object_set (G_OBJECT (layout), "column-spacing", 6, NULL);
57 gtk_container_add (GTK_CONTAINER (window), layout);
58
59 /* channel labels */
60 name = g_path_get_basename (file_name1);
61 if ((ext = strrchr (name, '.')))
62 *ext = '\0';
63 label = gtk_label_new (name);
64 g_free (name);
65 gtk_grid_attach (GTK_GRID (layout), label, 0, 0, 1, 1);
66
67 gtk_grid_attach (GTK_GRID (layout), gtk_label_new ("|"), 1, 0, 1, 1);
68
69 name = g_path_get_basename (file_name2);
70 if ((ext = strrchr (name, '.')))
71 *ext = '\0';
72 label = gtk_label_new (name);
73 g_free (name);
74 gtk_grid_attach (GTK_GRID (layout), label, 2, 0, 1, 1);
75
76 /* mix slider */
77 scale =
78 gtk_scale_new_with_range (GTK_ORIENTATION_HORIZONTAL, 0.0, 1.0,
79 1.0 / 200.0);
80 gtk_range_set_value (GTK_RANGE (scale), 0.0);
81 gtk_widget_set_size_request (scale, 200, -1);
82 gtk_widget_set_hexpand (scale, TRUE);
83 gtk_grid_attach (GTK_GRID (layout), scale, 0, 1, 3, 1);
84 g_signal_connect (scale, "value-changed",
85 G_CALLBACK (value_changed_callback), volume);
86
87 gtk_widget_show_all (GTK_WIDGET (window));
88 }
89
90 static void
message_received(GstBus * bus,GstMessage * message,GstPipeline * pipeline)91 message_received (GstBus * bus, GstMessage * message, GstPipeline * pipeline)
92 {
93 const GstStructure *s;
94
95 s = gst_message_get_structure (message);
96 g_print ("message from \"%s\" (%s): ",
97 GST_STR_NULL (GST_ELEMENT_NAME (GST_MESSAGE_SRC (message))),
98 gst_message_type_get_name (GST_MESSAGE_TYPE (message)));
99 if (s) {
100 gchar *sstr;
101
102 sstr = gst_structure_to_string (s);
103 g_print ("%s\n", sstr);
104 g_free (sstr);
105 } else {
106 g_print ("no message details\n");
107 }
108 }
109
110 static void
eos_message_received(GstBus * bus,GstMessage * message,GstPipeline * pipeline)111 eos_message_received (GstBus * bus, GstMessage * message,
112 GstPipeline * pipeline)
113 {
114 message_received (bus, message, pipeline);
115 gtk_main_quit ();
116 }
117
118 static void
dynamic_link(GstPadTemplate * templ,GstPad * newpad,gpointer user_data)119 dynamic_link (GstPadTemplate * templ, GstPad * newpad, gpointer user_data)
120 {
121 GstPad *target = GST_PAD (user_data);
122
123 gst_pad_link (newpad, target);
124 gst_object_unref (target);
125 }
126
127 static void
make_mixer_channel(GstElement * pipeline,GstElement * mix,gchar * file_name)128 make_mixer_channel (GstElement * pipeline, GstElement * mix, gchar * file_name)
129 {
130 GstElement *filesrc, *decodebin, *volume, *convert, *format;
131 GstCaps *caps;
132
133 /* prepare mixer channel */
134 filesrc = gst_element_factory_make ("filesrc", NULL);
135 decodebin = gst_element_factory_make ("decodebin", NULL);
136 volume = gst_element_factory_make ("volume", NULL);
137 convert = gst_element_factory_make ("audioconvert", NULL);
138 format = gst_element_factory_make ("capsfilter", NULL);
139 gst_bin_add_many (GST_BIN (pipeline), filesrc, decodebin, volume, convert,
140 format, NULL);
141 gst_element_link (filesrc, decodebin);
142 gst_element_link_many (volume, convert, format, mix, NULL);
143
144 /* configure elements */
145 g_object_set (filesrc, "location", file_name, NULL);
146 g_object_set (volume, "volume", (num_vol == 0) ? 1.0 : 0.0, NULL);
147
148 caps = gst_caps_from_string ("audio/x-raw, "
149 "format = (string) S16LE, " "channels = (int) 2");
150 g_object_set (format, "caps", caps, NULL);
151 gst_caps_unref (caps);
152
153 /* remember volume element */
154 volumes[num_vol++] = (GObject *) volume;
155
156 /* handle dynamic pads */
157 g_signal_connect (G_OBJECT (decodebin), "pad-added",
158 G_CALLBACK (dynamic_link), gst_element_get_static_pad (volume, "sink"));
159 }
160
161 int
main(int argc,char * argv[])162 main (int argc, char *argv[])
163 {
164 GstElement *pipeline = NULL;
165 GstElement *mix, *convert, *sink;
166 GstBus *bus;
167
168 if (argc < 3) {
169 g_print ("Usage: audiomix <file1> <file2>\n");
170 return 1;
171 }
172
173 gst_init (&argc, &argv);
174 gtk_init (&argc, &argv);
175
176 /* prepare tail of pipeline */
177 pipeline = gst_pipeline_new ("audiomix");
178 mix = gst_element_factory_make ("adder", NULL);
179 convert = gst_element_factory_make ("audioconvert", NULL);
180 sink = gst_element_factory_make ("autoaudiosink", NULL);
181 gst_bin_add_many (GST_BIN (pipeline), mix, convert, sink, NULL);
182 gst_element_link_many (mix, convert, sink, NULL);
183
184 /* prepare mixer channel strips */
185 make_mixer_channel (pipeline, mix, argv[1]);
186 make_mixer_channel (pipeline, mix, argv[2]);
187
188 /* setup message handling */
189 bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));
190 gst_bus_add_signal_watch_full (bus, G_PRIORITY_HIGH);
191 g_signal_connect (bus, "message::error", (GCallback) message_received,
192 pipeline);
193 g_signal_connect (bus, "message::warning", (GCallback) message_received,
194 pipeline);
195 g_signal_connect (bus, "message::eos", (GCallback) eos_message_received,
196 pipeline);
197
198 /* setup GUI */
199 setup_gui (pipeline, argv[1], argv[2]);
200
201 /* go to main loop */
202 gst_element_set_state (pipeline, GST_STATE_PLAYING);
203 gtk_main ();
204 gst_element_set_state (pipeline, GST_STATE_NULL);
205 gst_object_unref (pipeline);
206 gst_object_unref (bus);
207
208 return 0;
209 }
210