ApsaraVideo Live:Get started with RTS

Prerequisites

• An Alibaba Cloud account is created and real-name verification is complete. To create an Alibaba Cloud account, visit the Alibaba Cloud official website. For more information, see Create an Alibaba Cloud account.

• An ingest domain and a streaming domain are available. ICP filing for the domain names is complete. For more information, see the ICP Filing documentation.

  Note

  • If you are in a live center outside the Chinese mainland and set Acceleration Region to Outside Chinese Mainland for the domain names, ICP filing is not required.

  • If the ingest domain and the streaming domain are second-level domain names under the same top-level domain name, you need to apply for an ICP number only for the top-level domain name.

Basic procedure

1. Activate ApsaraVideo Live

2. Add an ingest domain and a streaming domain

3. Add CNAME records

4. Associate the streaming domain with the ingest domain

5. (Optional) Configure SSL certificates

6. Enable RTS

7. (Optional) Configure custom URL signing

8. Generate ingest and streaming URLs

9. Start RTS-based stream ingest

10. Start RTS playback

Activate ApsaraVideo Live

1. Log on to the Alibaba Cloud official website. In the top navigation bar, choose Products > Media Services > ApsaraVideo Live. The ApsaraVideo Live homepage appears.

2. Click Activate Now.

3. On the ApsaraVideo Live activation page, select Pay-By-Traffic as the metering method. Read and agree to the ApsaraVideo Live Terms of Service.

4. Click Activate Now.

Add an ingest domain and a streaming domain

To use RTS, you must add an ingest domain and a streaming domain.

1. Log on to the ApsaraVideo Live console.

2. In the left-side navigation pane, click Domains. The Domain Management page appears.

3. Click Add Domain.

4. Configure the domain name based on your business requirements.

   

   Parameter	Option	Description
   Domain Name	N/A	Enter the domain name that you want to accelerate. Take note of the following points: In most cases, use a subdomain name as an accelerated domain name. Example: demo.aliyundoc.com. ApsaraVideo Live does not support wildcard domain names, such as *.aliyundoc.com. Duplicate accelerated domain names are not allowed. If the error message The specified domain already exists is displayed, check whether the domain name is added to other cloud services such as ApsaraVideo VOD, Dynamic Route for CDN (DCDN), Secure CDN (SCDN), or Video Surveillance System. After you activate ApsaraVideo Live, you can add a maximum of 20 domain names to ApsaraVideo Live for each Alibaba Cloud account. If the average daily peak bandwidth of your domain names exceeds 50 Mbit/s, you can submit a ticket to increase the quota of domain names. Make sure that the quota increase does not incur business risks. For more information about how to submit a ticket, see Contact us. Content that is served from the domain name must comply with the limits of ApsaraVideo Live. For more information, see Verify a domain name. Note The specified subdomain name must belong to the same Alibaba Cloud account. When you add a subdomain name, ApsaraVideo Live verifies the ownership of the subdomain name. If the subdomain name belongs to a different account, an error message appears.
   Live Center	N/A	A live center provides media processing services for live streams in the cloud, such as snapshot capture, recording, transcoding, and production studio. The live center of an ingest domain must be located in the same region as that of the bound streaming domain. This parameter cannot be modified once set. For more information about how to select a live center, see How do I select a live center?.
   Domain Type	Streaming Domain Ingest Domain	The type of the domain name. You can add an ingest domain or a streaming domain. This parameter cannot be modified once set. Note To add an ingest domain, select Ingest Domain for Domain Type. To add a streaming domain, select Streaming Domain for Domain Type. You cannot add a domain name as both an ingest domain and a streaming domain.
   Acceleration Region	Chinese Mainland	The edge group in which content delivery is to be accelerated. Valid values: Chinese Mainland For an ingest domain, if the streamers are located in the Chinese mainland, select Chinese Mainland. For a streaming domain, if the audience is located in the Chinese mainland, select Chinese Mainland. Apply for ICP filing from the Ministry of Industry and Information Technology of China for the domain name. We recommend that you use the Alibaba Cloud ICP Filing system. Global For an ingest domain, if the streamers are located in the Chinese mainland, Hong Kong (China), Macao (China), Taiwan (China), and other countries and regions, select Global. For a streaming domain, if the audience is located in the Chinese mainland, Hong Kong (China), Macao (China), Taiwan (China), and other countries and regions, select Global. Apply for ICP filing from the Ministry of Industry and Information Technology of China for the domain name. We recommend that you use the Alibaba Cloud ICP Filing system. Outside Chinese Mainland For an ingest domain, if the streamers are located in countries and regions outside the Chinese mainland, including Hong Kong (China), Macao (China), and Taiwan (China), select Outside Chinese Mainland. For a streaming domain, if the audience is located in countries and regions outside the Chinese mainland, including Hong Kong (China), Macao (China), and Taiwan (China), select Outside Chinese Mainland. If you select Outside Chinese Mainland and the live center is located outside the Chinese mainland, you do not need to apply for ICP filing for the domain name. If you select Outside Chinese Mainland and the live center is located in the Chinese mainland, you must apply for ICP filing for the domain name. We recommend that you apply for ICP filing by using the Alibaba Cloud ICP Filing system. Note For more information about how to select an edge group, see How do I select the acceleration region for a domain name?.
   	Global
   	Outside Chinese Mainland

5. Click Next.

Add CNAME records

Before you use RTS, you must add CNAME records at your DNS service provider to map your ingest domain and streaming domain to the CNAME that is assigned by ApsaraVideo Live. The following example shows how to add a CNAME record when your DNS service provider is Alibaba Cloud. For information about how to add a CNAME record at other DNS service providers, see Add a CNAME record.

1. Log on to the Alibaba Cloud DNS console.

2. In the left-side navigation pane, click Domain Name Resolution. The Domain Name Resolution page appears.

3. Find the domain name for which you want to add a CNAME record and click DNS Settings in the Actions column.

4. Click Add DNS Record and configure the parameters that are described in the following table.

   Parameter	Description
   Record Type	Select CNAME from the drop-down list.
   Hostname	Specify a prefix for the domain name. For more information about regular prefixes of domain names and sample domain names, see the following table.
   DNS Request Source	Use the default value.
   Record Value	Enter the CNAME that you obtained.
   TTL Period	Use the default value.

   Prefix	Sample domain name	Description
   demo	demo.aliyundoc.com	The subdomain name.
   @	aliyundoc.com	The root domain name.
   *	*.aliyundoc.com	The wildcard domain name.

5. Click OK.

Associate the streaming domain with the ingest domain

RTS uses the edge ingest method. To ingest and play streams, you must associate the streaming domain with the ingest domain.

1. On the Domain Management page, find the streaming domain that you added and click Domain Settings in the Actions column. The Streaming Management > Basic Settings page appears.

2. Click the Basic Information tab.

   On this tab, you can view the CNAME, Added At, Domain Type, Live Center, Edge Group, and Quota Limits information.

   Note

   • You can manage quotas of ApsaraVideo Live only in the China (Beijing), China (Shanghai), China (Shenzhen), and Singapore regions. To increase quotas for other centers, submit a ticket. For more information, see Contact us.

   • For more information about quota limits, see Quota management.

   • For more information about how to change the edge group, see Change the edge group.

3. Click the Stream Ingest Information tab.

4. Click Add Stream Ingest Information or the Edit icon next to Ingest Domain and select the ingest domain that you want to associate.

(Optional) Configure SSL certificates

For security reasons, if you want to implement RTS in a native browser, you must configure Secure Sockets Layer (SSL) certificates for the ingest domain and the streaming domain. For more information, see Configure HTTPS secure acceleration.

Enable RTS

1. Log on to the ApsaraVideo Live console.

2. In the left-side navigation pane, click Domains. The Domain Management page appears.

3. Find the streaming domain for which you want to enable RTS and click Domain Settings in the Actions column.

4. On the page that appears, choose Streaming Management > RTS.

5. Turn on RTS.

6. In the dialog box that appears, choose RTS 1.0 and turn on HTML5 Auto Transcoding.

   The WebRTC of native browsers does not support B-frames and the AAC audio format. To ensure smooth playback, the feature of auto transcoding for HTML5 playback performs adaptive transcoding.

   • If you use a browser to play a stream that contains B-frames and AAC audio, the B-frames are removed and the audio format is converted. You are charged for standard transcoding fees.

   • If you use a browser to play a stream that contains AAC audio but does not contain B-frames, the audio format is converted. You are charged for audio-only transcoding fees.

   • If you use a browser to play a stream and have configured a transcoding template, both the feature of auto transcoding for HTML5 playback and the transcoding template take effect. The transcoding is billed only once.

   • If you use Native RTS SDK to play a stream, transcoding is not required because the SDK supports B-frames and the AAC audio format.

   Note

   • Wait a few minutes and then check whether the configurations for RTS take effect.

   • To map an ingest domain to multiple streaming domains, you must bind one or more sub-streaming domains to a main streaming domain. For more information, see Bind a sub-streaming domain to a main streaming domain.

   • RTS and standard streaming can share the same streaming domain. However, we recommend that you configure a separate streaming domain for RTS because RTS uses User Datagram Protocol (UDP) while standard streaming uses Transmission Control Protocol (TCP).

(Optional) Configure custom URL signing

The URL signing feature can be used to protect resources on origin servers from unauthorized access and downloads. By default, URL signing is enabled for a domain name that you add.

You can use the default URL signing settings or custom URL signing settings based on your business requirements. If you use the default URL signing settings, no additional configuration is required. If you do not want to use the default settings, you can specify the Primary Key, Secondary Key, and Validity Period parameters.

1. On the Domains page, find the streaming domain for which RTS is enabled and click Domain Settings in the Actions column.

2. Choose Streaming Management > Access Control. The Access Control page appears.

3. Click the URL Signing tab. Then, click Change Settings.

   Note

   When URL signing is enabled, you can click Change Settings to modify the URL signing settings. When URL signing is disabled, you can turn on URL Signing and then configure the URL signing settings.

4. Configure the URL signing settings.

   The following table describes the parameters.

   Parameter	Description
   Authentication Type	ApsaraVideo Live streaming domains support only the authentication type of Type A to protect resources on the origin server. Note If URL signing fails, an HTTP status code 403 is returned. In this case, you must recalculate the signature. Invalid MD5 values Example: X-Tengine-Error:denied by req auth: invalid md5hash=de7bfdc915ced05e17380a149bd760be Invalid timestamps Example: X-Tengine-Error:denied by req auth: expired timestamp=1439469547
   Primary Key	After you add a domain name, ApsaraVideo Live generates a random primary key for the domain name. To view the primary key, click Domains in the left-side navigation pane and click the domain name. On the page that appears, choose Streaming Management > Access Control. Then, view the primary key on the URL Signing tab. You can also change the primary key.
   Secondary Key	Specify a custom secondary key.
   Validity Period	The signed URL can be used to initiate stream ingest or streaming requests only within the validity period. Persistent connections are established for stream ingest and streaming. Stream ingest and streaming requests that are initiated within the validity period are not dropped after the validity period expires. New stream ingest and streaming requests fail to be initiated after the validity period expires. The default validity period for a signed URL under a domain name that you add is 1 day or 1,440 minutes. You can specify a custom validity period for the signed URL. The minimum value is 1 minute. There is no upper limit.

Generate ingest and streaming URLs

You can generate an ingest URL and a streaming URL by using the ApsaraVideo Live console or construct the URLs by using the concatenation rules.

Start RTS-based stream ingest

We recommend that you use the RTMP format for RTS-based stream ingest. In the following example, OBS Studio is used to ingest streams over RTMP. For more information about how to ingest streams over RTS, see Stream ingest for RTS.

1. Download and install OBS Studio. Download link: OBS Studio.

2. Run OBS Studio.

3. In the menu bar, choose File > Settings.

4. On the Settings page, click Stream and configure the following parameters.

   

   Parameter	Description
   Service	Select Custom....
   Server	Enter the signed ingest URL that is generated. Example: rtmp://demo.aliyundoc.com/app/stream?auth_key=1543302081-0-0-9c6e7c8190c10bdfb3c0************.
   Stream Key	Leave this parameter empty.

5. Optional: On the Settings page, click Output and configure the following parameters to remove B-frames.

   • Output Mode: Advanced

   • Keyframe Interval (seconds, 0=auto): 1

   • CPU Usage Preset (higher = less CPU): veryfast

   • Profile: baseline

   • Tune: zerolatency

   

6. Go to the homepage of OBS Studio. Find the Sources section, add a source, and click Start Streaming.

   

Start RTS playback

The following table lists the players integrated with RTS SDK for RTS playback. Alibaba Cloud RTS provides demos for both mobile and web clients.

• Players:

  Player	References
  ApsaraVideo Player for mobile clients	Integrate Native RTS SDK with ApsaraVideo Player SDK
  Third-party players that are based on FFmpeg	Integrate Native RTS SDK with a third-party player that is based on FFmpeg
  ApsaraVideo Player for Web	SDK overview

• For information about the RTS demo, see Play an RTS stream.

Other operations: verify the latency of RTS

You can add a time calibrator URL during stream ingest to verify the latency of RTS by comparing the streaming time with UTC. OBS Studio is used in this example.

Go to the homepage of OBS Studio. Add a time calibrator URL in the Sources section, and click Start Streaming.