Set up the source stream using OBS

Open Broadcaster Software (OBS) Studio can send a camera, capture device, or test source to an MK.IO live event over RTMP. Configure the source, encoder, and MK.IO input URL before you start streaming.

Install OBS Studio

1. Download and install OBS for your operating system on the Open Broadcaster Software website.
2. Start the application. OBS starts with a default scene but with no inputs selected.

Add a video source

1. From the Sources panel, select the add icon.
2. Select Video Capture Device.
3. Select Add Existing, then select OK.
4. From the Device list, select the video input for the broadcast.
5. Leave the remaining settings unchanged and select OK.

The input appears in the Sources panel and the video appears in the preview.

Add a browser test source

If you do not have a capture device ready, you can use a browser source for a first test:

1. Select the add icon under Sources.
2. Select Browser.
3. Name the source Clock and enter https://vclock.com as its URL.

If the source shows a cookie-consent prompt, right-click the browser source, select Interact, and accept the prompt.

Add an audio source

1. From the Sources panel, select the add icon.
2. Select Audio Input Capture.
3. Select Add Existing, then select OK.
4. From the Device list, select the audio capture device for the broadcast.
5. Leave the remaining settings unchanged and select OK.

The audio capture device appears in the audio mixer.

Set up streaming and advanced encoding settings

Before continuing, start the live event and copy its Input URL.

1. Select Settings in the Controls panel.
2. Select Stream in the left menu.
3. From Service, select Show all, then select Custom.
4. In Server, paste the RTMP input URL without the final /stream suffix.
5. In Stream Key, enter a valid stream name, such as stream.
6. Select Output in the left menu.
7. Set Output Mode to Advanced.
8. On the Streaming tab, select the encoder settings for the computer’s processor and capabilities:
   • Set Audio Encoder to FFmpeg AAC or CoreAudio AAC.
   • Set Video Encoder to x264.
   • Use constant bitrate (CBR) rate control.
   • Match Keyframe interval to the Input key frame interval configured in MK.IO.

Set audio settings

1. Select Output > Audio.
2. Set Audio Bitrate for the source.
3. Set Sample Rate to 48 kHz.

Set video settings

1. Select Output > Video.
2. Set Output (Scaled) Resolution to 1920x1080.
3. Set Common FPS Values for the source.
4. Select OK.

Start streaming

The combined video and audio bitrate must not exceed the live event’s bandwidth limit.

1. In the Controls panel, select Start Streaming.
2. Return to the live event in MK.IO, then select Apply.
3. Confirm that the source appears in the preview.
4. Copy the playback URLs for use in a compatible player or application.

Check the OBS status

Use the OBS status bar to check the source while it is running:

• Bitrate shows how much data OBS sends each second. It should remain stable.
• Dropped frames should remain at 0 percent. A rising value indicates a network or processor problem.
• FPS shows the frame rate sent by OBS.
• CPU usage should remain below 60 percent. Usage near 90 percent can affect the output quality.