--- /dev/null
+/* GStreamer
+ * Copyright (C) 2021 Damian Hobson-Garcia <dhobsong@igel.co.jp>
+ *
+ * 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 application showing v4l2src cropping */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/gst.h>
+
+#define PLAY_TIME_SEC 5
+
+struct rect
+{
+ guint left;
+ guint top;
+ guint width;
+ guint height;
+};
+
+static gboolean
+bus_call (GstBus * bus, GstMessage * msg, gpointer data)
+{
+ GMainLoop *loop = (GMainLoop *) data;
+
+ switch (GST_MESSAGE_TYPE (msg)) {
+
+ case GST_MESSAGE_EOS:
+ g_print ("End of stream\n");
+ g_main_loop_quit (loop);
+ break;
+
+ case GST_MESSAGE_ERROR:{
+ gchar *debug;
+ GError *error;
+
+ gst_message_parse_error (msg, &error, &debug);
+ g_free (debug);
+
+ g_printerr ("Error: %s\n", error->message);
+ g_error_free (error);
+
+ g_main_loop_quit (loop);
+ break;
+ }
+ default:
+ break;
+ }
+
+ return TRUE;
+}
+
+static void
+on_crop_bounds (GstElement * element, GParamSpec * pspec, void *data)
+{
+ GValue bounds = { 0 };
+ int i;
+ union
+ {
+ struct rect rect;
+ guint vals[4];
+ } crop_bounds;
+
+ struct rect crop;
+
+ g_value_init (&bounds, G_PARAM_SPEC_VALUE_TYPE (pspec));
+ g_object_get_property (G_OBJECT (element), "crop-bounds", &bounds);
+
+ if (gst_value_array_get_size (&bounds) != 4) {
+ g_error ("Invalid crop bounds received");
+ return;
+ }
+
+ for (i = 0; i < 4; i++) {
+ const GValue *val = gst_value_array_get_value (&bounds, i);
+ if (!G_VALUE_HOLDS_INT (val)) {
+ g_error ("Invalid crop bounds value received");
+ return;
+ }
+ crop_bounds.vals[i] = g_value_get_int (val);
+ }
+
+ g_print ("Crop bounds: @(%d, %d), %dx%d\n", crop_bounds.rect.left,
+ crop_bounds.rect.top, crop_bounds.rect.width, crop_bounds.rect.height);
+
+ /* Crop out a region from the bottom right quandrant of the
+ * crop bounding region */
+ crop.left = (crop_bounds.rect.width - crop_bounds.rect.left) / 2;
+ crop.top = (crop_bounds.rect.height - crop_bounds.rect.top) / 2;
+ crop.width = crop.left / 2;
+ crop.height = crop.left / 2;
+
+ g_print ("Setting crop region to @(%d, %d), %dx%d\n", crop.left, crop.top,
+ crop.width, crop.height);
+
+ g_object_set (G_OBJECT (element),
+ "crop-left", crop.left,
+ "crop-top", crop.top,
+ "crop-right", crop_bounds.rect.width - crop.left - crop.width,
+ "crop-bottom", crop_bounds.rect.height - crop.top - crop.height, NULL);
+}
+
+static const gchar *device = "/dev/video0";
+static const gchar *videosink = "autovideosink";
+
+static GOptionEntry entries[] = {
+ {"device", 'd', 0, G_OPTION_ARG_STRING, &device, "V4L2 Camera Device",
+ NULL},
+ {"videosink", 's', 0, G_OPTION_ARG_STRING, &videosink, "Video Sink to use",
+ NULL},
+ {NULL}
+};
+
+static gboolean
+send_eos (gpointer user_data)
+{
+ GstElement *pipeline = user_data;
+
+ gst_element_send_event (pipeline, gst_event_new_eos ());
+ return FALSE;
+}
+
+int
+main (int argc, char *argv[])
+{
+ GMainLoop *loop;
+
+ GstElement *pipeline, *source, *conv, *sink;
+ GstBus *bus;
+ guint bus_watch_id;
+ GError *error = NULL;
+ GOptionContext *context;
+ gboolean ret;
+
+ context = g_option_context_new ("- test v4l2src crop");
+ g_option_context_add_main_entries (context, entries, GETTEXT_PACKAGE);
+ g_option_context_add_group (context, gst_init_get_option_group ());
+ ret = g_option_context_parse (context, &argc, &argv, &error);
+ g_option_context_free (context);
+
+ if (!ret) {
+ g_print ("option parsing failed: %s\n", error->message);
+ g_error_free (error);
+ return 1;
+ }
+
+ gst_init (&argc, &argv);
+
+ loop = g_main_loop_new (NULL, FALSE);
+
+ /* Create gstreamer elements */
+ pipeline = gst_pipeline_new ("v4l2src crop sample");
+ source = gst_element_factory_make ("v4l2src", "source");
+ conv = gst_element_factory_make ("videoconvert", "converter");
+ sink = gst_element_factory_make (videosink, "video-output");
+
+ if (!pipeline || !source || !conv || !sink) {
+ g_printerr ("One or more elements could not be created. Exiting.\n");
+ return -1;
+ }
+
+ /* Set up the v4l2src element */
+ g_object_set (G_OBJECT (source), "device", device, NULL);
+
+ /* Add a message handler */
+ bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));
+ bus_watch_id = gst_bus_add_watch (bus, bus_call, loop);
+ gst_object_unref (bus);
+
+ gst_bin_add_many (GST_BIN (pipeline), source, conv, sink, NULL);
+ gst_element_link_many (source, conv, sink, NULL);
+
+ /* Connect a callback to be notified when the crop bounding region is
+ * retreived from the V4L2 device */
+ g_signal_connect (source, "notify::crop-bounds", (GCallback) on_crop_bounds,
+ NULL);
+
+ /* Set the pipeline to "playing" state */
+ gst_element_set_state (pipeline, GST_STATE_PLAYING);
+
+ /* Stop the playback after specified time */
+ g_timeout_add_seconds (PLAY_TIME_SEC, send_eos, pipeline);
+
+ g_main_loop_run (loop);
+
+ /* Out of the main loop, clean up nicely */
+ g_print ("Stopping playback\n");
+ gst_element_set_state (pipeline, GST_STATE_NULL);
+
+ g_print ("Deleting pipeline\n");
+ gst_object_unref (GST_OBJECT (pipeline));
+ g_source_remove (bus_watch_id);
+ g_main_loop_unref (loop);
+
+ return 0;
+}
projects / platform / upstream / gstreamer.git / commitdiff