Getting prayer times onto your TVs

What you need

Time: 45 minutes for the first TV, 15 for each one after

  • OpenMasjidOS installed, with OpenMasjid Display added.
  • A TV with an HDMI socket.
  • A decoder box, one per TV.
  • A network cable to the TV, or good Wi-Fi there.

How this works

One masjid computer works out the prayer times and produces a video picture for each screen. It sends that picture over your own network. At each TV, a small box receives it and puts it out over HDMI.

There is no computer behind each TV, and no cable running from the office to the prayer hall.

masjid computer ──your network──▶ decoder box ──HDMI──▶ TV

What a decoder box is

A decoder box is a small device, usually the size of a deck of cards. It takes a video stream from a network and plays it out of an HDMI socket. They are sold as RTSP decoders, IP video decoders, or network video receivers.

What to look for when buying one

We are not going to name a model. Nobody has told us which boxes this masjid has actually run for a year. Recommending untested hardware, bought with a masjid’s own money, is not something this guide will do.

So here is what the box must do, which is enough to shop with:

Requirement Why
Plays RTSP streams This is what Display produces. A box that only does HDMI or USB is no use.
1080p output Prayer times need to be readable across a hall.
Wired network, not only Wi-Fi A prayer-hall TV should not depend on Wi-Fi reaching a far corner.
Starts playing on power-up, with no remote After a power cut the screen must come back by itself.
Remembers its stream address So nobody re-types it every time.

Step 1 — Make the screen in Display

  1. Open OpenMasjid Display, then the Screens tab.
  2. Add a screen. Give it a Screen name and the Room.
  3. Set Normally shows to the timetable this TV will display.
  4. Copy the video link the screen entry gives you.
Result:

The screen is listed, and shows Offline until a box starts playing it.

Step 2 — Wire up the TV

  1. Plug the decoder box into the TV with an HDMI cable.
  2. Plug the network cable into the box.
  3. Power the box on.
  4. Set the TV to that HDMI input.

Step 3 — Point the box at the screen

Every box has a slightly different settings page, reached either on the TV with its remote or from a browser on your network.

  1. Open the box's settings.
  2. Find the field for the stream, URL, or RTSP address.
  3. Paste the link from step 1.
  4. Save, and turn on any auto-play or auto-start option.
Result:

The TV shows your prayer timetable. In the Screens tab, the entry stops saying Offline.

Step 4 — Prove it survives a power cut

  1. Unplug the decoder box.
  2. Wait ten seconds.
  3. Plug it back in and do not touch anything else.
Result:

Within a minute the timetable is back on the TV, with nobody pressing anything.

Cameras and a laptop on the same screens

Once the first screen works, the same wiring carries more than a timetable.

A camera. Add it under Sources in Display with its own network address, and any screen can show it. This is what puts the imam on a screen in the overflow room or the women's section.

A laptop or a recording. You need an HDMI-to-network encoder, which is the opposite of a decoder: it takes an HDMI cable in and puts a network stream out. Add that stream under Sources like a camera.

Adding the rest of the building

For each new TV: add a screen in Display, copy its link, wire up a box, paste the link. The masjid computer does not change, and you do not pay anybody per screen.

Checkpoint

One TV shows the prayer timetable, and the Screens tab does not say Offline. The picture comes back on its own after you unplug the box and plug it back in.

If something goes wrong

What you seeWhyWhat to do
The TV shows no signal.Wrong HDMI input, or the box has no power.Cycle the TV’s inputs. Check the box has a light on it.
The box is on but the picture is black.The stream address is wrong, or the box cannot reach the network.Paste the link again from the Screens tab, exactly. Check the network cable at the box.
The screen says Offline in Display.Nothing is playing that stream.The box is not connected. Check its network cable and its stream address.
The picture stutters or breaks up.Not enough network for the video, or a weak box.Lower Picture quality on the source. Use a wired connection. Then try one screen on its own to see whether the box is the limit.
The TV is blank after a power cut.The box does not auto-play.Turn on auto-start in its settings. If it has none, that model is unsuitable — this is why you test one first.
The picture is sideways.Orientation on the timetable does not match how the TV is hung.Set Orientation on the timetable in Display, not on the TV.