1 /* GStreamer
2 * Copyright (C) 2010 Stefan Kost <stefan.kost@nokia.com>
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19 /* demo for using gstcontroler with camera capture for e.g. bracketing
20 *
21 * gcc `pkg-config --cflags --libs gstreamer-0.10 gstreamer-controller-0.10` camctrl.c -o camctrl
22 *
23 * TODO:
24 * - handle stream status and switch capture thread to SCHED_RR/FIFO
25 * - we want some feedback about how precisely a program can be realized
26 * - we might want to adjust the framerate to handle hardware limmits
27 * - we e.g. can't change resolution per frame right now
28 */
29
30 #include <gst/gst.h>
31 #include <gst/controller/gstinterpolationcontrolsource.h>
32 #include <gst/controller/gstdirectcontrolbinding.h>
33
34 static void
event_loop(GstElement * bin)35 event_loop (GstElement * bin)
36 {
37 GstBus *bus;
38 GstMessage *message = NULL;
39
40 bus = gst_element_get_bus (GST_ELEMENT (bin));
41
42 while (TRUE) {
43 message = gst_bus_poll (bus, GST_MESSAGE_ANY, -1);
44
45 switch (message->type) {
46 case GST_MESSAGE_EOS:
47 gst_message_unref (message);
48 return;
49 case GST_MESSAGE_WARNING:
50 case GST_MESSAGE_ERROR:{
51 GError *gerror;
52 gchar *debug;
53
54 gst_message_parse_error (message, &gerror, &debug);
55 gst_object_default_error (GST_MESSAGE_SRC (message), gerror, debug);
56 gst_message_unref (message);
57 g_error_free (gerror);
58 g_free (debug);
59 return;
60 }
61 default:
62 gst_message_unref (message);
63 break;
64 }
65 }
66 }
67
68 static void
set_program(GstObject * elem,GstStructure * prog)69 set_program (GstObject * elem, GstStructure * prog)
70 {
71 const GstStructure *s;
72 GstControlSource *cs;
73 GstClockTime ts, dur;
74 gdouble v;
75 const GValue *frame;
76 GHashTable *css;
77 gint i, j;
78 const gchar *name;
79
80 css = g_hash_table_new (g_str_hash, g_str_equal);
81
82 ts = 0;
83 dur = gst_util_uint64_scale_int (GST_SECOND, 1, 15);
84
85 /* loop over each image in prog */
86 for (i = 0; i < gst_structure_n_fields (prog); i++) {
87 GST_DEBUG ("ctrl on %" GST_TIME_FORMAT, GST_TIME_ARGS (ts));
88
89 frame =
90 gst_structure_get_value (prog, gst_structure_nth_field_name (prog, i));
91 s = gst_value_get_structure (frame);
92 for (j = 0; j < gst_structure_n_fields (s); j++) {
93 name = gst_structure_nth_field_name (s, j);
94 cs = g_hash_table_lookup (css, name);
95 if (!cs) {
96 cs = gst_interpolation_control_source_new ();
97 gst_object_add_control_binding (elem,
98 gst_direct_control_binding_new (elem, name, cs));
99 g_object_set (cs, "mode", GST_INTERPOLATION_MODE_NONE, NULL);
100 g_hash_table_insert (css, (gpointer) name, cs);
101 gst_object_unref (cs);
102 }
103 gst_structure_get_double (s, name, &v);
104 gst_timed_value_control_source_set ((GstTimedValueControlSource *) cs, ts,
105 v);
106 GST_DEBUG (" %s = %lf", name, v);
107 }
108 ts += dur;
109 }
110
111 g_hash_table_unref (css);
112 }
113
114 gint
main(gint argc,gchar ** argv)115 main (gint argc, gchar ** argv)
116 {
117 GstElement *bin;
118 GstElement *src, *cvt, *fmt, *enc, *sink;
119 GstCaps *caps;
120 GstStructure *prog;
121
122 /* init gstreamer */
123 gst_init (&argc, &argv);
124
125 /* create a new bin to hold the elements */
126 bin = gst_pipeline_new ("camera");
127
128 /* create elements */
129 if (!(sink = gst_element_factory_make ("multifilesink", NULL))) {
130 GST_WARNING ("Can't create element \"multifilesink\"");
131 return -1;
132 }
133 g_object_set (sink, "location", "image%02d.jpg", NULL);
134
135 if (!(enc = gst_element_factory_make ("jpegenc", NULL))) {
136 GST_WARNING ("Can't create element \"jpegenc\"");
137 return -1;
138 }
139
140 if (!(fmt = gst_element_factory_make ("capsfilter", NULL))) {
141 GST_WARNING ("Can't create element \"capsfilter\"");
142 return -1;
143 }
144 caps =
145 gst_caps_from_string
146 ("video/x-raw, width=640, height=480, framerate=(fraction)15/1");
147 g_object_set (fmt, "caps", caps, NULL);
148
149 if (!(cvt = gst_element_factory_make ("videoconvert", NULL))) {
150 GST_WARNING ("Can't create element \"videoconvert\"");
151 return -1;
152 }
153
154 if (!(src = gst_element_factory_make ("v4l2src", NULL))) {
155 GST_WARNING ("Can't create element \"v4l2src\"");
156 return -1;
157 }
158
159 /* add objects to the main bin */
160 gst_bin_add_many (GST_BIN (bin), src, cvt, fmt, enc, sink, NULL);
161
162 /* link elements */
163 if (!gst_element_link_many (src, cvt, fmt, enc, sink, NULL)) {
164 GST_WARNING ("Can't link elements");
165 return -1;
166 }
167
168 /* program a pattern of events */
169 #if 0
170 prog = gst_structure_from_string ("program"
171 ", image00=(structure)\"image\\,contrast\\=0.0\\;\""
172 ", image01=(structure)\"image\\,contrast\\=0.3\\;\""
173 ", image02=(structure)\"image\\,contrast\\=1.0\\;\""
174 ", image03=(structure)\"image\\,contrast\\=0.05\\;\";", NULL);
175 #endif
176 #if 1
177 prog = gst_structure_from_string ("program"
178 ", image00=(structure)\"image\\,brightness\\=1.0\\,contrast\\=0.0\\;\""
179 ", image01=(structure)\"image\\,brightness\\=0.5\\,contrast\\=0.3\\;\""
180 ", image02=(structure)\"image\\,brightness\\=0.25\\,contrast\\=1.0\\;\""
181 ", image03=(structure)\"image\\,brightness\\=0.0\\,contrast\\=0.05\\;\";",
182 NULL);
183 #endif
184 set_program (GST_OBJECT (src), prog);
185 g_object_set (src, "num-buffers", gst_structure_n_fields (prog),
186 "device", argv[1] ? argv[1] : "/dev/video0", NULL);
187
188 /* prepare playback */
189 gst_element_set_state (bin, GST_STATE_PAUSED);
190
191 /* play and wait */
192 gst_element_set_state (bin, GST_STATE_PLAYING);
193
194 /* mainloop and wait for eos */
195 event_loop (bin);
196
197 /* stop and cleanup */
198 gst_element_set_state (bin, GST_STATE_NULL);
199 gst_object_unref (GST_OBJECT (bin));
200 return 0;
201 }
202