Mux klv data from h264 by mpegtsmux

Question

I need mux klv metadata in h264 stream. I have created an application. But the stream is reproduced only until klv data is inserted. When I stop pushing klv data, the whole stream stops. What is the correct method for asynchronous klv multiplexing data using mpegtsmux?

Klv data must be inserted into the following production pipeline:

v4l2src input-src=Camera ! videorate drop-only=true  ! 'video/x-raw, format=(string)NV12, width=1920, height=1088, framerate=25/1' ! ce_h264enc  target-bitrate=6000000 idrinterval=25 intraframe-interval=60 ! queue ! mpegtsmux  alignment=7 ! udpsink host=192.168.0.1 port=3000 -v

This pipeline is built in the application. To insert klv-metedata appsrc, the following is created:

appSrc = gst_element_factory_make("appsrc", nullptr);
gst_app_src_set_caps (GST_APP_SRC (appSrc), gst_caps_new_simple("meta/x-klv", "parsed", G_TYPE_BOOLEAN, TRUE, "sparse", G_TYPE_BOOLEAN, TRUE, nullptr));
g_object_set(appSrc, "format", GST_FORMAT_TIME, nullptr);

Then appsrc is associated with the pipeline:

gst_bin_add(GST_BIN(pipeline), appSrc);
gst_element_link(appSrc, mpegtsmux);

Here is the push function:

void AppSrc::pushData(const std::string &data)
{
GstBuffer *buffer = gst_buffer_new_allocate(nullptr, data.size(), nullptr);
GstMapInfo map;
GstClock *clock;
GstClockTime abs_time, base_time;

gst_buffer_map (buffer, &map, GST_MAP_WRITE);
memcpy(map.data, data.data(), data.size());
gst_buffer_unmap (buffer, &map);

GST_OBJECT_LOCK (element);
clock = GST_ELEMENT_CLOCK (element);
base_time = GST_ELEMENT (element)->base_time;
gst_object_ref (clock);
GST_OBJECT_UNLOCK (element);
abs_time = gst_clock_get_time (clock);
gst_object_unref (clock);

GST_BUFFER_PTS (buffer) = abs_time - base_time;
GST_BUFFER_DURATION (buffer) = gst_util_uint64_scale_int (1, GST_SECOND, 1);

gst_app_src_push_buffer(GST_APP_SRC(element), buffer);
}

Gstreamer version is 1.6.1.

What could be wrong with my code? I would be grateful for your help.

I can push dummy klv packages to support the video stream. But I do not want to pollute the flow, and I am sure that there should be a finer solution.

, GST_STREAM_FLAG_SPARSE, . .

GstEvent* stream_start = gst_event_new_stream_start("klv-04");
gst_event_set_stream_flags(stream_start, GST_STREAM_FLAG_SPARSE);
GstPad* pad = gst_element_get_static_pad(GST_ELEMENT(element), "src"); 
gst_pad_push_event (pad, stream_start);

, gstreamer GST_STREAM_FLAG_SPARSE, , appsrc .

diff --git a/libs/gst/base/gstcollectpads.c b/libs/gst/base/gstcollectpads.c
index 8edfe41..14f9926 100644
--- a/libs/gst/base/gstcollectpads.c
+++ b/libs/gst/base/gstcollectpads.c
@@ -1440,7 +1440,8 @@ gst_collect_pads_recalculate_waiting (GstCollectPads * pads)
   if (!GST_COLLECT_PADS_STATE_IS_SET (data, GST_COLLECT_PADS_STATE_WAITING)) {
     /* start waiting */
     gst_collect_pads_set_waiting (pads, data, TRUE);
-        result = TRUE;
+      if (!GST_COLLECT_PADS_STATE_IS_SET (data, GST_COLLECT_PADS_STATE_LOCKED))
+          result = TRUE;
       }
     }
   }

10 klv.

Answer 1

,

, appsrc , . :

gst_element_link(appSrc, mpegtsmux);

:

gst_element_link(appSrc, appSrcQueue);
gst_element_link(appSrcQueue, mpegtsmux);

, mpegtsmux , do-timestamping, TRUE, .

, , - gst-inspect, , .