Start a live stream

After you subscribe to Stream, you can create Live Inputs in Dash or via the API. Broadcast to your new Live Input using RTMPS or SRT. SRT supports newer video codecs and makes using accessibility features, such as captions and multiple audio tracks, easier.

First time live streaming? You will need software to send your video to Cloudflare. Learn how to go live on Stream using OBS Studio.

​​ Use the dashboard

Step 1: Create a live input via the Stream Dashboard Open external link .

Step 2: Copy the RTMPS URL and key, and use them with your live streaming application. We recommend using Open Broadcaster Software (OBS) Open external link to get started.

Step 3: Go live and preview your live stream in the Stream Dashboard

In the Stream Dashboard, within seconds of going live, you will see a preview of what your viewers will see. To add live video playback to your website or app, refer to Play videos.

​​ Use the API

To start a live stream programmatically, make a POST request to the /live_inputs endpoint:

Request
curl -X POST \
--header "Authorization: Bearer <API_TOKEN>" \
--data '{"meta": {"name":"test stream"},"recording": { "mode": "automatic" }}' \
https://api.cloudflare.com/client/v4/accounts/{account_id}/stream/live_inputs

Response
{
  "uid": "f256e6ea9341d51eea64c9454659e576",
  "rtmps": {
    "url": "rtmps://live.cloudflare.com:443/live/",
    "streamKey": "MTQ0MTcjM3MjI1NDE3ODIyNTI1MjYyMjE4NTI2ODI1NDcxMzUyMzcf256e6ea9351d51eea64c9454659e576"
  },
  "created": "2021-09-23T05:05:53.451415Z",
  "modified": "2021-09-23T05:05:53.451415Z",
  "meta": {
    "name": "test stream"
  },
  "status": null,
  "recording": {
    "mode": "automatic",
    "requireSignedURLs": false,
    "allowedOrigins": null
  }
}

​​ Optional API parameters

API Reference Docs for /live_inputs Open API docs link

​​ Manage live inputs

You can update live inputs by making a PUT request:

Request
$ curl --request PUT \
https://api.cloudflare.com/client/v4/accounts/{account_id}/stream/live_inputs/{input_id} \
--header "Authorization: Bearer <API_TOKEN>" \
--data '{"meta": {"name":"test stream 1"},"recording": { "mode": "automatic", "timeoutSeconds": 10 }}'

Delete a live input by making a DELETE request:

Request
$ curl --request DELETE \
https://api.cloudflare.com/client/v4/accounts/{account_id}/stream/live_inputs/{input_id} \
--header "Authorization: Bearer <API_TOKEN>"

​​ Recommendations, requirements and limitations

​​ Recommendations

• Your creators should use an appropriate bitrate for their live streams, typically well under 12Mbps (12000Kbps). High motion, high frame rate content typically should use a higher bitrate, while low motion content like slide presentations should use a lower bitrate.
• Your creators should use a GOP duration Open external link (keyframe interval) of between 2 to 8 seconds. The default in most encoding software and hardware, including Open Broadcaster Software (OBS), is within this range. Setting a lower GOP duration will reduce latency for viewers, while also reducing encoding efficiency. Setting a higher GOP duration will improve encoding efficiency, while increasing latency for viewers. This is a tradeoff inherent to video encoding, and not a limitation of Cloudflare Stream.
• When possible, select CBR (constant bitrate) instead of VBR (variable bitrate) as CBR helps to ensure a stable streaming experience while preventing buffering and interruptions.

• For lowest latency, use a GOP size (keyframe interval) of 1 or 2 seconds.
• Broadcast to the RTMP endpoint if possible.
• If using OBS, select the “ultra low” latency profile.

​​ Requirements

• Closed GOPs are required. This means that if there are any B frames in the video, they should always refer to frames within the same GOP. This setting is the default in most encoding software and hardware, including OBS Studio Open external link .
• Stream Live only supports H.264 video and AAC audio codecs as inputs. This requirement does not apply to inputs that are relayed to Stream Connect outputs. Stream Live supports ADTS but does not presently support LATM.
• Clients must be configured to reconnect when a disconnection occurs. Stream Live is designed to handle reconnection gracefully by continuing the live stream.

​​ Limitations

• Watermarks cannot yet be used with live videos.
• If a live video exceeds seven days in length, the recording will be truncated to seven days. Only the first seven days of live video content will be recorded.