Sync time code

Cargo.lock

@@ -493,6 +493,7 @@ dependencies = [
  "gstreamer-gl",
  "gstreamer-gl-egl",
  "gstreamer-gl-x11",
+ "gstreamer-net",
  "gstreamer-pbutils",
  "gstreamer-play",
  "gstreamer-player",

examples/Cargo.toml

@@ -43,6 +43,7 @@ winit = { version = "0.29", optional = true, default-features = false, features
 atomic_refcell = "0.1"
 data-encoding = "2.0"
 once_cell = "1"
+gst-net = { workspace = true }
 
 [target.'cfg(windows)'.dependencies]
 windows = { version = "0.56", features=["Win32_Graphics_Direct3D11",

examples/src/bin/overlay-composition.rs

@@ -52,7 +52,14 @@ unsafe impl Send for LayoutWrapper {}
 fn create_pipeline() -> Result<gst::Pipeline, Error> {
     gst::init()?;
 
+    // Create the NTP clock and wait for synchronization.
+    let clock = gst_net::NtpClock::new(None, "pool.ntp.org", 123, gst::ClockTime::ZERO);
+    println!("Syncing to NTP clock");
+    clock.wait_for_sync(gst::ClockTime::from_seconds(5))?;
+    println!("Synced to NTP clock");
+
     let pipeline = gst::Pipeline::default();
+    pipeline.set_clock(Some(&clock))?;
 
     // The videotestsrc supports multiple test patterns. In this example, we will use the
     // pattern with a white ball moving around the video's center point.
@@ -68,17 +75,29 @@ fn create_pipeline() -> Result<gst::Pipeline, Error> {
     let caps = gst_video::VideoCapsBuilder::new()
         .width(800)
         .height(800)
-        .framerate((15, 1).into())
         .build();
     let capsfilter = gst::ElementFactory::make("capsfilter")
         .property("caps", &caps)
         .build()?;
 
     let videoconvert = gst::ElementFactory::make("videoconvert").build()?;
+
+    let timestamper = gst::ElementFactory::make("timecodestamper").build()?;
+    timestamper.set_property_from_str("set", "always");
+    timestamper.set_property_from_str("source", "rtc");
+
+    let timeoverlay = gst::ElementFactory::make("timeoverlay").build()?;
+    timeoverlay.set_property("font-desc", "Sans Bold 26");
+    timeoverlay.set_property_from_str("time-mode", "time-code");
+    timeoverlay.set_property_from_str("halignment", "center");
+    timeoverlay.set_property_from_str("valignment", "bottom");
+    timeoverlay.set_property("color", 4200427042u32);
+
+    let videoconvert2 = gst::ElementFactory::make("videoconvert").build()?;
     let sink = gst::ElementFactory::make("autovideosink").build()?;
 
-    pipeline.add_many([&src, &overlay, &capsfilter, &videoconvert, &sink])?;
-    gst::Element::link_many([&src, &overlay, &capsfilter, &videoconvert, &sink])?;
+    pipeline.add_many([&src, &overlay, &capsfilter, &videoconvert, &timestamper, &timeoverlay, &videoconvert2, &sink])?;
+    gst::Element::link_many([&src, &overlay, &capsfilter, &videoconvert, &timestamper, &timeoverlay, &videoconvert2, &sink])?;
 
     // The PangoFontMap represents the set of fonts available for a particular rendering system.
     let fontmap = pangocairo::FontMap::new();