--- /dev/null
+/**
+ * @file nnstreamer_example_decoder.c
+ * @date 4 Oct 2018
+ * @brief Tensor stream example with tensor decoder
+ * @see https://github.com/nnsuite/nnstreamer
+ * @author Jinhyuck Park <jinhyuck83.park@samsung.com>
+ * @bug No known bugs.
+ *
+ * NNStreamer example for image recognition with only gstreamer plug-in's include decoder.
+ *
+ * Pipeline :
+ * v4l2src -- tee -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- textoverlay -- videoconvert -- ximagesink
+ * | |
+ * --- videoscale -- tensor_converter -- tensor_filter -- tensor_decoder
+ *
+ *
+ * 'tensor_filter' for image recognition.
+ * Download tflite moel 'Mobilenet_1.0_224_quant' from below link,
+ * https://github.com/tensorflow/tensorflow/blob/master/tensorflow/contrib/lite/g3doc/models.md#image-classification-quantized-models
+ *
+ * 'tensor decoder' updates recognition result links to text_sink of textoverlay.
+ *
+ * Run example :
+ * Before running this example, GST_PLUGIN_PATH should be updated for nnstreamer plug-in.
+ * $ export GST_PLUGIN_PATH=$GST_PLUGIN_PATH:<nnstreamer plugin path>
+ * $ ./nnstreamer_example_decoder
+ */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <glib.h>
+#include <gst/gst.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 tflite model info.
+ */
+typedef struct
+{
+ gchar *model_path; /**< tflite model file path */
+} tflite_info_s;
+
+/**
+ * @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 */
+
+ gboolean running; /**< true when app is running */
+ guint received; /**< received buffer count */
+ tflite_info_s tflite_info; /**< tflite model info */
+} AppData;
+
+/**
+ * @brief Data for pipeline and result.
+ */
+static AppData g_app;
+
+/**
+ * @brief Free data in tflite info structure.
+ */
+static void
+_tflite_free_info (tflite_info_s * tflite_info)
+{
+ g_return_if_fail (tflite_info != NULL);
+
+ if (tflite_info->model_path) {
+ g_free (tflite_info->model_path);
+ tflite_info->model_path = NULL;
+ }
+
+}
+
+/**
+ * @brief Check tflite model and load labels.
+ *
+ * This example uses 'Mobilenet_1.0_224_quant' for image classification.
+ */
+static gboolean
+_tflite_init_info (tflite_info_s * tflite_info, const gchar * path)
+{
+ const gchar tflite_model[] = "mobilenet_v1_1.0_224_quant.tflite";
+
+ g_return_val_if_fail (tflite_info != NULL, FALSE);
+
+ tflite_info->model_path = NULL;
+
+ /** check model file exists */
+ tflite_info->model_path = g_strdup_printf ("%s/%s", path, tflite_model);
+
+ if (access (tflite_info->model_path, F_OK) != 0) {
+ _print_log ("cannot find tflite model [%s]", tflite_info->model_path);
+ return FALSE;
+ }
+
+ return TRUE;
+}
+
+
+/**
+ * @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;
+ }
+
+ _tflite_free_info (&g_app.tflite_info);
+}
+
+/**
+ * @brief Function to print error message.
+ */
+static void
+_parse_err_message (GstMessage * message)
+{
+ gchar *debug;
+ GError *error;
+
+ g_return_if_fail (message != NULL);
+
+ 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 Function to print qos message.
+ */
+static void
+_parse_qos_message (GstMessage * message)
+{
+ GstFormat format;
+ guint64 processed;
+ guint64 dropped;
+
+ gst_message_parse_qos_stats (message, &format, &processed, &dropped);
+ _print_log ("format[%d] processed[%" G_GUINT64_FORMAT "] dropped[%"
+ G_GUINT64_FORMAT "]", format, processed, dropped);
+}
+
+/**
+ * @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;
+
+ case GST_MESSAGE_QOS:
+ _parse_qos_message (message);
+ break;
+
+ default:
+ break;
+ }
+}
+
+
+/**
+ * @brief Set window title.
+ * @param name GstXImageSink element name
+ * @param title window title
+ */
+static void
+_set_window_title (const gchar * name, const gchar * title)
+{
+ GstTagList *tags;
+ GstPad *sink_pad;
+ GstElement *element;
+
+ element = gst_bin_get_by_name (GST_BIN (g_app.pipeline), name);
+
+ g_return_if_fail (element != NULL);
+
+ 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);
+ }
+
+ gst_object_unref (element);
+}
+
+
+/**
+ * @brief Main function.
+ */
+int
+main (int argc, char **argv)
+{
+ const gchar tflite_model_path[] = "./tflite_model";
+ const gchar tflite_label[] = "./tflite_model/labels.txt";
+ /** 224x224 for tflite model */
+ const guint width = 224;
+ const guint height = 224;
+
+ gchar *str_pipeline;
+ gulong handle_id;
+ GstElement *element;
+
+ _print_log ("start app..");
+
+ /** init app variable */
+ g_app.running = FALSE;
+ g_app.received = 0;
+
+ _check_cond_err (_tflite_init_info (&g_app.tflite_info, tflite_model_path));
+
+ /** 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 pipeline */
+ str_pipeline =
+ g_strdup_printf
+ ("textoverlay name=overlay font-desc=\"Sans, 24\" ! videoconvert ! ximagesink name=img_test "
+ "v4l2src name=cam_src ! videoscale ! video/x-raw,width=640,height=480,format=RGB ! tee name=t_raw "
+ "t_raw. ! queue ! overlay.video_sink "
+ "t_raw. ! queue ! videoscale ! video/x-raw,width=%d,height=%d !tensor_converter !"
+ "tensor_filter framework=tensorflow-lite model=%s ! "
+ "tensor_decoder output-type=2 mode=image_labeling mode-option-1=%s ! overlay.text_sink ",
+ width, height, g_app.tflite_info.model_path, tflite_label);
+ g_app.pipeline = gst_parse_launch (str_pipeline, NULL);
+ g_free (str_pipeline);
+ _check_cond_err (g_app.pipeline != NULL);
+
+ /** bus and 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);
+
+ g_app.running = TRUE;
+
+ /** set window title */
+ _set_window_title ("img_test", "NNStreamer Example");
+
+ /** run main loop */
+ g_main_loop_run (g_app.loop);
+ /** quit when received eos or error message */
+ g_app.running = FALSE;
+ /** cam source element */
+ element = gst_bin_get_by_name (GST_BIN (g_app.pipeline), "cam_src");
+
+ 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;
+}