examples: Add an mpegtsmux example of prog-map usage.

Add an example of how to construct the prog-map structure for
the MPEG-TS muxers and assign streams to programs, and set PCR
and PMT PIDs.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/2039>

tests/examples/mpegts/meson.build

@@ -1,4 +1,4 @@
-foreach fname : ['ts-parser.c', 'ts-section-writer.c', 'ts-scte-writer.c']
+foreach fname : ['ts-parser.c', 'ts-section-writer.c', 'ts-scte-writer.c', 'tsmux-prog-map.c']
   exe_name = fname.split('.').get(0).underscorify()
 
   executable(exe_name,

tests/examples/mpegts/tsmux-prog-map.c

@@ -0,0 +1,99 @@
+/* GStreamer
+ *
+ * tsmux-prog-map.c: sample application to show how to construct the
+ * mpegtsmux prog-map property.
+ *
+ * MIT License
+ *
+ * Copyright (C) 2021 Jan Schmidt <jan@centricular.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.*
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/gst.h>
+
+/* Test pipeline with h264video on PID 101 and AAC audio on PID 102
+ * The streams will be assigned to Program #2, with PMT on PID 100, and
+ * the PCR on the video stream */
+#define TEST_PIPELINE "videotestsrc num-buffers=90 ! video/x-raw,framerate=30/1 ! x264enc ! queue ! .sink_101 mpegtsmux name=mux ! fakesink audiotestsrc samplesperbuffer=4800 num-buffers=30 ! audio/x-raw,rate=48000 ! fdkaacenc ! aacparse ! mux.sink_102"
+
+static void
+_on_bus_message (GstBus * bus, GstMessage * message, GMainLoop * mainloop)
+{
+  switch (GST_MESSAGE_TYPE (message)) {
+    case GST_MESSAGE_ERROR:
+    case GST_MESSAGE_EOS:
+      g_main_loop_quit (mainloop);
+      break;
+    default:
+      break;
+  }
+}
+
+int
+main (int argc, char **argv)
+{
+  GstElement *pipeline = NULL;
+  GError *error = NULL;
+  GstBus *bus;
+  GMainLoop *mainloop;
+  GstElement *muxer;
+  GstStructure *prog_map;
+
+  gst_init (&argc, &argv);
+
+  pipeline = gst_parse_launch (TEST_PIPELINE, &error);
+  if (error) {
+    g_print ("Error constructing pipeline: %s\n", error->message);
+    g_clear_error (&error);
+    return 1;
+  }
+
+  mainloop = g_main_loop_new (NULL, FALSE);
+
+  bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));
+  gst_bus_add_signal_watch (bus);
+  g_signal_connect (bus, "message", (GCallback) _on_bus_message, mainloop);
+
+  /* Configure the program map here. The elementary streams get their PIDs from the pad name.
+   * Assign them to program # 2, with PMT on PID 100 */
+
+  muxer = gst_bin_get_by_name (GST_BIN (pipeline), "mux");
+
+  prog_map = gst_structure_new ("x-prog-map",
+      "sink_101", G_TYPE_INT, 2, "sink_102", G_TYPE_INT, 2,
+      "PMT_2", G_TYPE_UINT, 100, "PCR_2", G_TYPE_STRING, "sink_101", NULL);
+  g_object_set (muxer, "prog-map", prog_map, NULL);
+
+  gst_element_set_state (pipeline, GST_STATE_PLAYING);
+
+  g_main_loop_run (mainloop);
+
+  gst_element_set_state (pipeline, GST_STATE_NULL);
+
+  gst_object_unref (pipeline);
+  gst_object_unref (bus);
+
+  return 0;
+}