Linux Publisher Usage


In order to begin a broadcast session, you will need to discover the video device to use. The device code included with the Linux SDK can be used for cameras that support H264 output.

To do so, you issue the following command in a terminal - replacing the X with the desired video device number:

v4l2-ctl -d /dev/videoX --list-formats

As an example v4l2-ctl -d /dev/video0 --list-formats outputs something similar to the following:

 Index       : 0
  Type        : Video Capture
  Pixel Format: 'MJPG' (compressed)
  Name        : Motion-JPEG

  Index       : 1
  Type        : Video Capture
  Pixel Format: 'YUYV'
  Name        : YUYV 4:2:2

With a USB camera connected that supports H264 output, issuing the above command with /dev/video1 will print something of the following:

  Index       : 0
    Type        : Video Capture
    Pixel Format: 'H264' (compressed)
    Name        : H.264

With the desired device found, you can setup the r5config to be consumed.


You will then provide 1 as the video index in the r5config in order to use that device for a broadcast session. Along with the video index, you also specify the desired resolution and format.

The full configuration will look like the following:

config.video = 1;
config.width = 1920;
config.height = 1080;
config.video_format = fourcc('H', '2', '6', '4');


To start, you will want to loader the shared libary:

libfuncs pointer;
pointer.handle = dlopen(so_path_selected, RTLD_LAZY);

Session Start

If the shared library is successfully loaded and, either using the provided device control or your own, start a broadcast session:

if (pointer.handle) {
  pointer.get_version = (pget_version)dlsym((void*)pointer.handle, "get_version");
  pointer.create_session = (pcreate_session)dlsym((void*)pointer.handle, "create_session");
  pointer.close_session = (pclose_session)dlsym((void*)pointer.handle, "close_session");
  uint32_t version = pointer.get_version();

  printf("Red5Pro SDK version %d.%d.%d  \n", ((version >> 16) & 0xFFFF) , ((version >> 8) & 0xFF) , ((version) & 0xFF));

  r5session* session = pointer.create_session();

  if (session && session->mem_ptr) {

    r5device* vfl2 = (r5device*)malloc(sizeof(r5device));
    session->set_r5camera(session->mem_ptr, vfl2);

    if (!session->init(session->mem_ptr, session->config)) {
      return 0; // publishing successfully
    } else {
      return 1; // there was a problem

And the set_config function to define the r5config settings as described in previous section:

voic set_config (r5config *config) {

  conf->audio = 0xFF;
  conf->video = 1;
  conf->width = 1920;
  conf->height = 1080;
  conf->video_format = fourcc('H','2','6','4');
  conf->audio_rate = 16000;
  conf->channel_count = 1;
  conf->video_bitrate = 750;
  conf->video_framerate = 30;
  conf->protocol = r5_rtsp;
  strcpy(conf->contextName, "live");
  strcpy(conf->hostName, "xxx.xxx.xxx.xxx");
  strcpy(conf->streamName, "stream1");
  conf->recordType = R5RecordTypeLive;
  conf->rtp_aux_out = NULL;
  conf->statusCallback = &print_status;
  conf->remoteCallback = NULL;


Replace the hostName value of xxx.xxx.xxx.xxx with the IP of your Red5 Pro Server deployment.

Session Close

Be sure to properly clean up resources once you are done broadcasting:

r5device* cam = session->get_r5camera(session->mem_ptr);



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