gstreamer/tests/examples/v4l2/camctrl.c
2017-06-06 11:30:07 -04:00

201 lines
6.1 KiB
C

/* GStreamer
* Copyright (C) 2010 Stefan Kost <stefan.kost@nokia.com>
*
* 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 St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/* demo for using gstcontroler with camera capture for e.g. bracketing
*
* gcc `pkg-config --cflags --libs gstreamer-0.10 gstreamer-controller-0.10` camctrl.c -o camctrl
*
* TODO:
* - handle stream status and switch capture thread to SCHED_RR/FIFO
* - we want some feedback about how precisely a program can be realized
* - we might want to adjust the framerate to handle hardware limmits
* - we e.g. can't change resolution per frame right now
*/
#include <gst/gst.h>
#include <gst/controller/gstinterpolationcontrolsource.h>
#include <gst/controller/gstdirectcontrolbinding.h>
static void
event_loop (GstElement * bin)
{
GstBus *bus;
GstMessage *message = NULL;
bus = gst_element_get_bus (GST_ELEMENT (bin));
while (TRUE) {
message = gst_bus_poll (bus, GST_MESSAGE_ANY, -1);
switch (message->type) {
case GST_MESSAGE_EOS:
gst_message_unref (message);
return;
case GST_MESSAGE_WARNING:
case GST_MESSAGE_ERROR:{
GError *gerror;
gchar *debug;
gst_message_parse_error (message, &gerror, &debug);
gst_object_default_error (GST_MESSAGE_SRC (message), gerror, debug);
gst_message_unref (message);
g_error_free (gerror);
g_free (debug);
return;
}
default:
gst_message_unref (message);
break;
}
}
}
static void
set_program (GstObject * elem, GstStructure * prog)
{
const GstStructure *s;
GstControlSource *cs;
GstClockTime ts, dur;
gdouble v;
const GValue *frame;
GHashTable *css;
gint i, j;
const gchar *name;
css = g_hash_table_new (g_str_hash, g_str_equal);
ts = 0;
dur = gst_util_uint64_scale_int (GST_SECOND, 1, 15);
/* loop over each image in prog */
for (i = 0; i < gst_structure_n_fields (prog); i++) {
GST_DEBUG ("ctrl on %" GST_TIME_FORMAT, GST_TIME_ARGS (ts));
frame =
gst_structure_get_value (prog, gst_structure_nth_field_name (prog, i));
s = gst_value_get_structure (frame);
for (j = 0; j < gst_structure_n_fields (s); j++) {
name = gst_structure_nth_field_name (s, j);
cs = g_hash_table_lookup (css, name);
if (!cs) {
cs = gst_interpolation_control_source_new ();
gst_object_add_control_binding (elem,
gst_direct_control_binding_new (elem, name, cs));
g_object_set (cs, "mode", GST_INTERPOLATION_MODE_NONE, NULL);
g_hash_table_insert (css, (gpointer) name, cs);
gst_object_unref (cs);
}
gst_structure_get_double (s, name, &v);
gst_timed_value_control_source_set ((GstTimedValueControlSource *) cs, ts,
v);
GST_DEBUG (" %s = %lf", name, v);
}
ts += dur;
}
g_hash_table_unref (css);
}
gint
main (gint argc, gchar ** argv)
{
GstElement *bin;
GstElement *src, *cvt, *fmt, *enc, *sink;
GstCaps *caps;
GstStructure *prog;
/* init gstreamer */
gst_init (&argc, &argv);
/* create a new bin to hold the elements */
bin = gst_pipeline_new ("camera");
/* create elements */
if (!(sink = gst_element_factory_make ("multifilesink", NULL))) {
GST_WARNING ("Can't create element \"multifilesink\"");
return -1;
}
g_object_set (sink, "location", "image%02d.jpg", NULL);
if (!(enc = gst_element_factory_make ("jpegenc", NULL))) {
GST_WARNING ("Can't create element \"jpegenc\"");
return -1;
}
if (!(fmt = gst_element_factory_make ("capsfilter", NULL))) {
GST_WARNING ("Can't create element \"capsfilter\"");
return -1;
}
caps =
gst_caps_from_string
("video/x-raw, width=640, height=480, framerate=(fraction)15/1");
g_object_set (fmt, "caps", caps, NULL);
if (!(cvt = gst_element_factory_make ("videoconvert", NULL))) {
GST_WARNING ("Can't create element \"videoconvert\"");
return -1;
}
if (!(src = gst_element_factory_make ("v4l2src", NULL))) {
GST_WARNING ("Can't create element \"v4l2src\"");
return -1;
}
/* add objects to the main bin */
gst_bin_add_many (GST_BIN (bin), src, cvt, fmt, enc, sink, NULL);
/* link elements */
if (!gst_element_link_many (src, cvt, fmt, enc, sink, NULL)) {
GST_WARNING ("Can't link elements");
return -1;
}
/* programm a pattern of events */
#if 0
prog = gst_structure_from_string ("program"
", image00=(structure)\"image\\,contrast\\=0.0\\;\""
", image01=(structure)\"image\\,contrast\\=0.3\\;\""
", image02=(structure)\"image\\,contrast\\=1.0\\;\""
", image03=(structure)\"image\\,contrast\\=0.05\\;\";", NULL);
#endif
#if 1
prog = gst_structure_from_string ("program"
", image00=(structure)\"image\\,brightness\\=1.0\\,contrast\\=0.0\\;\""
", image01=(structure)\"image\\,brightness\\=0.5\\,contrast\\=0.3\\;\""
", image02=(structure)\"image\\,brightness\\=0.25\\,contrast\\=1.0\\;\""
", image03=(structure)\"image\\,brightness\\=0.0\\,contrast\\=0.05\\;\";",
NULL);
#endif
set_program (GST_OBJECT (src), prog);
g_object_set (src, "num-buffers", gst_structure_n_fields (prog),
"device", argv[1] ? argv[1] : "/dev/video0", NULL);
/* prepare playback */
gst_element_set_state (bin, GST_STATE_PAUSED);
/* play and wait */
gst_element_set_state (bin, GST_STATE_PLAYING);
/* mainloop and wait for eos */
event_loop (bin);
/* stop and cleanup */
gst_element_set_state (bin, GST_STATE_NULL);
gst_object_unref (GST_OBJECT (bin));
return 0;
}