StartPublishCdnStream
public StartPublishCdnStreamResponse StartPublishCdnStream(StartPublishCdnStreamRequest req)
throws TencentCloudSDKException
This API is used to mix streams and relay the mixed stream to CDNs. You can use this API to do the following:
1. Publish (also known as “relay”) the audio/video stream of one anchor to CDNs. For details, see example 2 (starting a task to relay the audio and video of a stream) and example 3 (starting a task to relay only the audio of a stream).
2. Mix the streams of multiple anchors in a room or in different rooms and publish the mixed stream to CDNs. You can use `AudioParams.SubscribeAudioList` to specify the users whose audios are mixed, and use `VideoParams.LayoutParams` to specify the layout of the anchors’ videos. For details, see example 1 (mixing streams and publishing the mixed stream to a CDN).
3. Mix multiple streams in a room according to a template and publish the mixed stream to CDNs. The TRTC backend will detect the change of anchors in the room and adjust the video layout automatically according to the stream mixing template. The following template types are supported:
- Floating: The entire screen is covered by the video image of the first user who enters the room, and the images of other users are displayed as small images in rows in the bottom-left corner in room entry sequence. The screen allows up to 4 rows of 4 small images, which float over the large main image. Up to 1 large image and 15 small images can be displayed.
- Grid: The images of all users split the screen evenly. The more the users, the smaller the image dimensions. Up to 16 images are supported.
- Screen sharing: This is designed for video conferencing and online education. The shared screen (or camera image of the anchor) is always displayed as the large main image, which occupies the left half of the screen, and the images of other users occupy the right half in up to two columns of up to eight small images each. Up to 1 large image and 15 small images can be displayed. If the upstream aspect ratio does not match the output, the large image on the left will be scaled and displayed in whole, while the small images on the right will be cropped.
4. Publish audio/video streams to up to 10 CDNs at a time. You can use `PublishCdnParams.PublishCdnUrl` to specify the URLs of the CDNs to publish to. To publish to Tencent Cloud’s CDN, set `PublishCdnParams.IsTencentCdn` to 1.
5. Configure a server-side callback to have Tencent Cloud send relay status updates to your server in the form of HTTP/HTTPS POST requests. To use the callback for relay events, please contact Technical Support.
6. The API supports four regions: Guangzhou, Shanghai, Beijing, and Hong Kong. If you relay to regions outside the Chinese mainland, select Hong Kong.
Notes:
1. **Because On-Cloud MixTranscoding is a paid feature, calling this API will incur MixTranscoding fees. For details, see [Billing of MixTranscoding and Relay to CDN](https://intl.cloud.tencent.com/document/product/647/47631?lang=en&pg=).**
2. **Relaying to third-party CDNs will incur relaying fees. For details, see [Billing of MixTranscoding and Relay to CDN](https://intl.cloud.tencent.com/document/product/647/47631?lang=en&pg=).**
Others:
1. You need to first call `StartPublishCdnStream` to start a relay task and get the task ID before you can use the `UpdatePublishCdnStream` API to modify the task and `StopPublishCdnStream` to stop the task.
2. To ensure the stability of relaying, you cannot switch between relaying audio only, relaying audio and video, and relaying video only for the same task.
3. To ensure the stability of relaying, you cannot change the video codec, audio codec, audio sample rate, audio bitrate, or sound channels using the `UpdatePublishCdnStream` API.
4. When you relay a single stream, specify both `AudioParams` and `VideoParams` to publish both audio and video, and specify only `AudioParams` to publish audio only. You cannot switch between the two modes during the relaying process. For `VideoParams`, set `Width`, `Height`, `Fps`, `Bitrate`, and `Gop` according to the actual settings used for publishing.
5. The `SequenceNumber` parameter is required when you call `UpdatePublishCdnStream` to change the relaying parameters. It ensures that multiple requests for the same relaying task are in the correct order. The value of `SequenceNumber` increases each time a new request is made for the same task. If `InternalError` is returned, try again using the same `SequenceNumber`. You don’t need to handle the `FailedOperation.OutdateRequest` error.
6. You can create a relay task before anchors enter a room, in which case you need to manually call `StopPublishCdnStream` to stop the task. If you don’t, after all the users whose streams are mixed leave the room, the TRTC backend will wait for the timeout period (`AgentParams.MaxIdleTime`) to elapse before stopping the relaying task.
- Parameters:
req - StartPublishCdnStreamRequest- Returns:
- StartPublishCdnStreamResponse
- Throws:
TencentCloudSDKException