# Deliver WebRTC streams to viewers for HLS playback using the Wowza Video REST API Learn how to use the Wowza Video REST API to deliver WebRTC streams to viewers through a CDN for playback over HLS. ## Before you start You should be familiar with the following concepts: - **API authentication** **methods**. We use JSON web tokens for API authentication. See [Authentication](/docs/wowza-video/about-the-rest-api/authentication) for more information. - **Environment variables**. We use environment variables for the API version and your JWT in the cURL API request examples in this topic to make it easier for you to copy, paste, and run commands in your Terminal or Command Prompt window. If you don't set environment variables for these values, you'll need to manually enter the correct values in the code samples throughout this tutorial. See [Tools for testing the API](/docs/wowza-video/about-the-rest-api/api-overview#tools-for-testing-the-api) for instructions. You should choose between the following two workflows: - Decide between the **live stream** or **transcoder** workflow. See Decide between a live stream or transcoder workflow for more information about these workflows. details summary Live stream workflow ## Live stream workflow ### 1. Create a live stream Create a live stream that receives a WebRTC source by sending a `POST` request to the `/live_streams` endpoint. You can use the following sample request, making sure to: - Set `encoder` to `other_webrtc`. - Set `aspect_ratio_height` to `1280`. This is the recommended value for WebRTC streams. - Set `aspect_ratio_width` to `720`. This is the recommended value for WebRTC streams. - Set `broadcast_location` to the region that's closest to your video source. - Set `delivery_method` to `push`. Wowza Video doesn't support`pull` or `cdn` connections for WebRTC. - Change any values unique to your broadcast, using the API reference documentation as a resource. See the **Endpoint Reference** button below. #### Sample request Endpoint Reference ```json curl -X POST \ -H "Content-Type: application/json" \ -H "Authorization: Bearer ${WV_JWT}" \ -d '{ "live_stream": { "aspect_ratio_height": 720, "aspect_ratio_width": 1280, "billing_mode": "pay_as_you_go", "broadcast_location": "us_west_california", "delivery_method": "push", "encoder": "other_webrtc", "name": "MyWebRTCStream", "transcoder_type": "transcoded" } }' "${WV_HOST}/api/${WV_VERSION}/live_streams" ``` #### Sample response The response includes: - An `id` for the live stream you'll use in the next step. - `source_connection_information` you'll use in the next step to configure the WebRTC publish page. - `sdp_url`, `application_name`, and `stream_name`. - A `url` in the `hosted_page` object. You'll give this to your viewers to watch the stream. ```json { "live_stream": { "id": "1234abcd", "name": "MyWebRTCStream", ... "encoder": "other_webrtc", ... "source_connection_information": { "sdp_url": "wss://[subdomain].entrypoint.video.wowza.com/webrtc-session.json", "application_name": "app-30zl5349", "stream_name": "32a5814b" }, ... "hosted_page": { "enabled": true, "title": "Hosted player page", "url": "https://player.video.wowza.com/qa/g7xr79xw/player.html", "sharing_icons": true, ... } } } ``` ### 2. Start the live stream Before you can connect to the stream through the WebRTC publish page in the next step, you need to start the live stream. You'll need the `[live_stream_id]` returned in step 1. Endpoint Reference ```json curl -X PUT \ -H "Authorization: Bearer ${WV_JWT}" \ "${WV_HOST}/api/${WV_VERSION}/live_streams/[live_stream_id]/start" ``` ### 3. Publish the WebRTC stream With the live stream started, you can now configure the WebRTC publish page as the source of the stream. 1. Go to wowza.com/webrtc/publish and grant access to your camera and microphone when prompted. The WebRTC hosted publish page is supported on the latest versions of Chrome and Safari, as well as Edge version 79 and later. ![WebRTC public publish page](/assets/cloud-webrtc-publish-page-public.6b0970261bc41296bc6fe9acae0ca94cb6e8a27c42988634bdc0b507fb29f4b4.71a4f21c.png) 2. Click the **Settings** button on the upper-right corner of the page. 3. Specify the following settings: - **SDP URL** – The `sdp_url` from the WebRTC `source_connection_information` object. - **Application Name** – The `application_name` from the WebRTC `source_connection_information` object. - **Stream Name** – The `stream_name` from the WebRTC `source_connection_information` object. - **Audio Bitrate** – You can leave **Audio Bitrate** set to the default value, **64**. - **Video Bitrate** – You can leave **Video Bitrate** set to the default value, **3500**. 4. Close the **Settings** dialog box to apply your changes. 5. To change which microphone to use, click the arrow next to the microphone icon. 6. To change the video source, click the arrow next to the video camera icon. To share your screen, select **Screen Share**. - The video source can't be changed after the broadcast is started. - Screen share functionality isn't supported on mobile devices or Safari. 7. Click **Publish**. ### 5. Test the connection Now that you have configured your source, you can fetch a thumbnail that shows a frame of the playing stream to visually confirm the stream is playing. You'll need the `[transcoder_id]` returned in step 1. Endpoint Reference ```json curl -X GET \ -H "Authorization: Bearer ${WV_JWT}" \ "${WV_HOST}/api/${WV_VERSION}/transcoders/[transcoder_id]/thumbnail_url" ``` info Alternatively, you can use the `playback_url` to configure the stream for playback in an HLS-compatible player. The URL is returned in a request to fetch stream target details. See the API reference for more information about these endpoints. ### 6. Stop the transcoder To avoid incurring additional billing charges, remember to stop the transcoder after the stream broadcast is over. Endpoint Reference ```json curl -X PUT \ -H "Authorization: Bearer ${WV_JWT}" \ "${WV_HOST}/api/${WV_VERSION}/transcoders/[transcoder_id]/stop" ``` ## More resources - Wowza Video REST API reference documentation - WebRTC workflows in Wowza Video - [Deliver WebRTC streams to viewers using the Wowza Video REST API](/docs/wowza-video/guides/video-source/encoder-camera/deliver-webrtc-streams-to-viewers)