[Example] application for webcam

1. add test pipeline for webcam.
2. use video-mixer to mix two video frames.

add tensor_filter and change pipeline later.

**Self evaluation:**
1. Build test: [*]Passed [ ]Failed [ ]Skipped
2. Run test: [*]Passed [ ]Failed [ ]Skipped

Signed-off-by: Jaeyun Jung <jy1210.jung@samsung.com>

diff --git a/nnstreamer_example/CMakeLists.txt b/nnstreamer_example/CMakeLists.txt
index 11f297b..85b234b 100644 (file)
--- a/nnstreamer_example/CMakeLists.txt
+++ b/nnstreamer_example/CMakeLists.txt
@@ -3,4 +3,5 @@ CMAKE_MINIMUM_REQUIRED(VERSION 2.8)
 ADD_SUBDIRECTORY(custom_example_passthrough)
 ADD_SUBDIRECTORY(custom_example_scaler)
 ADD_SUBDIRECTORY(custom_example_average)
+ADD_SUBDIRECTORY(example_cam)
 ADD_SUBDIRECTORY(example_sink)

diff --git a/nnstreamer_example/example_cam/CMakeLists.txt b/nnstreamer_example/example_cam/CMakeLists.txt
new file mode 100644 (file)
index 0000000..ef4e945
--- /dev/null
+++ b/nnstreamer_example/example_cam/CMakeLists.txt
@@ -0,0 +1,11 @@
+CMAKE_MINIMUM_REQUIRED(VERSION 2.8)
+
+# example app for webcam
+ADD_EXECUTABLE(nnstreamer_example_cam nnstreamer_example_cam.c)
+
+TARGET_LINK_LIBRARIES(nnstreamer_example_cam ${pkgs_LIBRARIES})
+TARGET_INCLUDE_DIRECTORIES(nnstreamer_example_cam PUBLIC ${pkgs_INCLUDE_DIRS})
+TARGET_COMPILE_OPTIONS(nnstreamer_example_cam PUBLIC ${pkgs_CFLAGS_OTHER})
+
+# do not install example app
+# INSTALL(TARGETS nnstreamer_example_cam RUNTIME DESTINATION ${EXEC_PREFIX})

diff --git a/nnstreamer_example/example_cam/nnstreamer_example_cam.c b/nnstreamer_example/example_cam/nnstreamer_example_cam.c
new file mode 100644 (file)
index 0000000..5b63268
--- /dev/null
+++ b/nnstreamer_example/example_cam/nnstreamer_example_cam.c
@@ -0,0 +1,263 @@
+/**
+ * @file       nnstreamer_example_cam.c
+ * @date       10 July 2018
+ * @brief      Tensor stream example
+ * @see                https://github.sec.samsung.net/STAR/nnstreamer
+ * @author     Jaeyun Jung <jy1210.jung@samsung.com>
+ * @bug                No known bugs.
+ *
+ * Sample code for tensor stream, this app shows video frame.
+ *
+ * Run example :
+ * ./nnstreamer_example_cam --gst-plugin-path=<nnstreamer plugin path>
+ */
+
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <gst/gst.h>
+#include <gst/app/gstappsrc.h>
+
+/**
+ * @brief Macro for debug mode.
+ */
+#ifndef DBG
+#define DBG TRUE
+#endif
+
+/**
+ * @brief Macro for debug message.
+ */
+#define _print_log(...) if (DBG) g_message (__VA_ARGS__)
+
+/**
+ * @brief Macro to check error case.
+ */
+#define _check_cond_err(cond) \
+  if (!(cond)) { \
+    _print_log ("app failed! [line : %d]", __LINE__); \
+    goto error; \
+  }
+
+/**
+ * @brief Data structure for app.
+ */
+typedef struct
+{
+  GMainLoop *loop; /**< main event loop */
+  GstElement *pipeline; /**< gst pipeline for data stream */
+  GstBus *bus; /**< gst bus for data pipeline */
+} AppData;
+
+/**
+ * @brief Data for pipeline and result.
+ */
+static AppData g_app;
+
+/**
+ * @brief Free resources in app data.
+ */
+static void
+_free_app_data (void)
+{
+  if (g_app.loop) {
+    g_main_loop_unref (g_app.loop);
+    g_app.loop = NULL;
+  }
+
+  if (g_app.bus) {
+    gst_bus_remove_signal_watch (g_app.bus);
+    gst_object_unref (g_app.bus);
+    g_app.bus = NULL;
+  }
+
+  if (g_app.pipeline) {
+    gst_object_unref (g_app.pipeline);
+    g_app.pipeline = NULL;
+  }
+}
+
+/**
+ * @brief Function to print error message.
+ */
+static void
+_parse_err_message (GstMessage * message)
+{
+  gchar *debug;
+  GError *error;
+
+  switch (GST_MESSAGE_TYPE (message)) {
+    case GST_MESSAGE_ERROR:
+      gst_message_parse_error (message, &error, &debug);
+      break;
+
+    case GST_MESSAGE_WARNING:
+      gst_message_parse_warning (message, &error, &debug);
+      break;
+
+    default:
+      return;
+  }
+
+  gst_object_default_error (GST_MESSAGE_SRC (message), error, debug);
+  g_error_free (error);
+  g_free (debug);
+}
+
+/**
+ * @brief Callback for message.
+ */
+static void
+_message_cb (GstBus * bus, GstMessage * message, gpointer user_data)
+{
+  switch (GST_MESSAGE_TYPE (message)) {
+    case GST_MESSAGE_EOS:
+      _print_log ("received eos message");
+      g_main_loop_quit (g_app.loop);
+      break;
+
+    case GST_MESSAGE_ERROR:
+      _print_log ("received error message");
+      _parse_err_message (message);
+      g_main_loop_quit (g_app.loop);
+      break;
+
+    case GST_MESSAGE_WARNING:
+      _print_log ("received warning message");
+      _parse_err_message (message);
+      break;
+
+    case GST_MESSAGE_STREAM_START:
+      _print_log ("received start message");
+      break;
+
+    default:
+      break;
+  }
+}
+
+/**
+ * @brief Check cam device connected.
+ */
+static gboolean
+_check_cam_device (const gchar * cam_dev)
+{
+  int fd;
+
+  if ((fd = open (cam_dev, O_RDONLY)) < 0) {
+    _print_log ("cannot detect cam, check your device and start again.");
+    return FALSE;
+  }
+
+  close (fd);
+  return TRUE;
+}
+
+/**
+ * @brief Set window title.
+ * @param element pointer to GstXImageSink
+ * @param title window title
+ */
+static void
+_set_window_title (GstElement * element, const gchar * title)
+{
+  GstTagList *tags;
+  GstPad *sink_pad;
+
+  sink_pad = gst_element_get_static_pad (element, "sink");
+
+  if (sink_pad) {
+    tags = gst_tag_list_new (GST_TAG_TITLE, title, NULL);
+    gst_pad_send_event (sink_pad, gst_event_new_tag (tags));
+    gst_object_unref (sink_pad);
+  }
+}
+
+/**
+ * @brief Main function.
+ */
+int
+main (int argc, char **argv)
+{
+  const gchar cam_dev[] = "/dev/video0";
+  const guint width = 640;
+  const guint height = 480;
+
+  gchar *str_pipeline;
+  gulong handle_id;
+  GstElement *element;
+
+  _print_log ("start app..");
+
+  /* check cam */
+  _check_cond_err (_check_cam_device (cam_dev));
+
+  /* init gstreamer */
+  gst_init (&argc, &argv);
+
+  /* main loop */
+  g_app.loop = g_main_loop_new (NULL, FALSE);
+  _check_cond_err (g_app.loop != NULL);
+
+  /* init data pipeline */
+  str_pipeline =
+      g_strdup_printf
+      ("v4l2src name=cam_src ! "
+      "video/x-raw,width=%d,height=%d,format=RGB,framerate=30/1 ! tee name=t_raw "
+      "videomixer name=mix "
+      "sink_0::xpos=0 sink_0::ypos=0 sink_0::zorder=0 sink_0::alpha=0.7 "
+      "sink_1::xpos=50 sink_1::ypos=50 sink_1::zorder=1 sink_1::alpha=0.5 ! "
+      "videoconvert ! xvimagesink name=img_mixed "
+      "t_raw. ! queue ! tensor_converter ! tensordec ! tee name=t_tensor "
+      "t_raw. ! queue ! mix.sink_0 "
+      "t_tensor. ! queue ! mix.sink_1 "
+      "t_tensor. ! queue ! videoconvert ! xvimagesink name=img_tensor",
+      width, height);
+  g_app.pipeline = gst_parse_launch (str_pipeline, NULL);
+  g_free (str_pipeline);
+  _check_cond_err (g_app.pipeline != NULL);
+
+  /* data message callback */
+  g_app.bus = gst_element_get_bus (g_app.pipeline);
+  _check_cond_err (g_app.bus != NULL);
+
+  gst_bus_add_signal_watch (g_app.bus);
+  handle_id = g_signal_connect (g_app.bus, "message",
+      (GCallback) _message_cb, NULL);
+  _check_cond_err (handle_id > 0);
+
+  /* start pipeline */
+  gst_element_set_state (g_app.pipeline, GST_STATE_PLAYING);
+
+  /* set window title */
+  element = gst_bin_get_by_name (GST_BIN (g_app.pipeline), "img_mixed");
+  _set_window_title (element, "Mixed");
+  gst_object_unref (element);
+
+  element = gst_bin_get_by_name (GST_BIN (g_app.pipeline), "img_tensor");
+  _set_window_title (element, "Tensor");
+  gst_object_unref (element);
+
+  /* run main loop */
+  g_main_loop_run (g_app.loop);
+
+  /* cam source element */
+  element = gst_bin_get_by_name (GST_BIN (g_app.pipeline), "cam_src");
+
+  /* quit when received eos or error message */
+  gst_element_set_state (element, GST_STATE_READY);
+  gst_element_set_state (g_app.pipeline, GST_STATE_READY);
+
+  g_usleep (200 * 1000);
+
+  gst_element_set_state (element, GST_STATE_NULL);
+  gst_element_set_state (g_app.pipeline, GST_STATE_NULL);
+
+  g_usleep (200 * 1000);
+  gst_object_unref (element);
+
+error:
+  _print_log ("close app..");
+  _free_app_data ();
+  return 0;
+}