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Pushing streams to Decklink SDI

Flussonic Media Server not only captures streams but also passes them to a Decklink SDI or HDMI card.

Output to Decklink SDI or Decklink HDMI cards

To enable pushing set the parameter push decklink://:

stream test {
  input udp://;
  push decklink://0 size=720x576 fps=50 deinterlace=true;

Flussonic decodes a stream and passes it to the specified Decklink device or a slot on the card itself (for example, 0). If necessary, you can use deinterlace=true to eliminate interlacing.

Decklink card modes

Usually a Decklink card supports a limited set of modes. Each mode is a combination of a frame size and FPS, encoded in Decklink format. For example, Hp50 is for 1920x1080 size with 50000/1000 FPS. When pushing a stream to a Decklink card, you can set the mode value in the format parameter. For example:

stream test {
  input ...;
  push decklink://0 format=Hi50;

The possible Decklink card modes are listed below.

    mode        description
    ntsc        720x486 at 30000/1001 fps (interlaced, lower field first)
    pal         720x576 at 25000/1000 fps (interlaced, upper field first)
    23ps        1920x1080 at 24000/1001 fps
    24ps        1920x1080 at 24000/1000 fps
    Hp25        1920x1080 at 25000/1000 fps
    Hp29        1920x1080 at 30000/1001 fps
    Hp30        1920x1080 at 30000/1000 fps
    Hp50        1920x1080 at 50000/1000 fps
    Hp59        1920x1080 at 60000/1001 fps
    Hp60        1920x1080 at 60000/1000 fps
    Hi50        1920x1080 at 25000/1000 fps (interlaced, upper field first)
    Hi59        1920x1080 at 30000/1001 fps (interlaced, upper field first)
    Hi60        1920x1080 at 30000/1000 fps (interlaced, upper field first)
    hp50        1280x720 at 50000/1000 fps
    hp59        1280x720 at 60000/1001 fps
    hp60        1280x720 at 60000/1000 fps
    4k23        3840x2160 at 24000/1001 fps
    4k24        3840x2160 at 24000/1000 fps
    4k25        3840x2160 at 25000/1000 fps
    4k29        3840x2160 at 30000/1001 fps
    4k30        3840x2160 at 30000/1000 fps
    4k50        3840x2160 at 50000/1000 fps
    4k59        3840x2160 at 60000/1001 fps
    4k60        3840x2160 at 60000/1000 fps
    4d23        4096x2160 at 24000/1001 fps
    4d24        4096x2160 at 24000/1000 fps
    4d25        4096x2160 at 25000/1000 fps
    4d29        4096x2160 at 30000/1001 fps
    4d30        4096x2160 at 30000/1000 fps
    4d50        4096x2160 at 50000/1000 fps
    4d59        4096x2160 at 60000/1001 fps
    4d60        4096x2160 at 60000/1000 fps

DeckLink duplex mode

To specify the duplex mode that allows choosing between the input and output direction of your DeckLink SDI card, use the following global configuration:

decklink 0 {
  profile two_half;

decklink 1 {
  profile two_half;

The example above shows the configuration of a half-duplex mode for a DeckLink Duo 2 card.

The DeckLink Quad 2 and the DeckLink Duo 2 cards have a specific physical to logical port mapping (see Fig. 1), which affects the configuration of duplex modes.

Figure 1. Physical to logical port mapping for DeckLink Quad 2 and Duo 2.

Decklink Duo2 and Quad2 mapping

Let's configure a DeckLink Quad 2 card so that all the ports are either used as input or output.

In this case, the two_half mode should be used.

To set the two_half mode for the DeckLink Quad 2 card, use the configuration below:

decklink 0 {
  profile two_half;
decklink 1 {
  profile two_half;
decklink 2 {
  profile two_half;
decklink 3 {
  profile two_half;