ApsaraVideo Live:Live stream transcoding

1. Log on to the ApsaraVideo Live console.

2. In the left-side navigation pane, choose Feature Management > Transcoding.

3. Select the domain name that you want to manage. On the Custom Transcoding tab, click Add to configure a transcoding template.

   

   The following table describes the parameters that you can configure for custom transcoding.

   Parameter	Description
   Application Name	The value of this parameter must be the same as the application name that is specified in the ingest URL. Otherwise, the transcoding template does not take effect.
   Template ID	The ID of the transcoding template. The value of this parameter is used to construct the URL of the transcoded stream. For more information, see Generate ingest and streaming URLs. You can append the template ID to the streaming URL to play the transcoded stream in the specified resolution. Note: The template ID must be different from default transcoding template IDs, including lld, lsd, lhd, lud, ld, sd, hd, and ud.
   Template Type	Valid values: Narrowband HD™ Transcoding and Audio-only Transcoding. An audio-only transcoding template removes the video content and generates an audio-only stream.
   Recommended Parameter Settings	Valid values: Low Definition, Standard Definition, High Definition, and Ultra High Definition. After you select one, the system automatically fills in the corresponding frame rate, bitrate, and resolution. You can modify them based on your business requirements.
   Resolution	The resolution of the output stream. Unit: pixels. You can specify a fixed resolution or configure source-based values. Source-based: If the resolution of the source stream is smaller than the adaptive resolution, the output resolution is equal to the source resolution. Otherwise, the output resolution is equal to the adaptive resolution. You can select one of the following adaptation methods: Adapted to Shorter Side Adapted to Longer Side Adapted to Orientation Fixed: Different prices apply to different resolutions. The following transcoding standards for billing are available: Low definition (LD): 640 × 480 and lower Standard definition (SD): 1280 × 720 and lower High definition (HD): 1920 × 1080 and lower 2K: 2560 × 1440 and lower 4K: 3840 × 2160 and lower Note You cannot specify a custom resolution higher than 1080p in the console. If your business scenario requires a resolution of 2K or 4K, submit a ticket. The transcoding standard for billing is determined by the width and height of the output video and is irrelevant to the preset template IDs for Narrowband HD™ transcoding, including ld, sd, hd, and ud. Take the SD resolution (1280 × 720) as an example. If the long edge of an output stream has no more than 1,280 pixels and the short edge has no more than 720 pixels, the transcoding standard for billing is SD. If the long edge of an output stream has more than 1,280 pixels, or the short edge has more than 720 pixels, the transcoding standard for billing is higher than SD.
   Video Frame Rate (FPS)	Source-based: If the frame rate of the source stream is within the specified limits, the output frame rate is equal to the source frame rate. If it exceeds the upper limit, the output is capped at the maximum frame rate. If it falls below the lower limit, the output is set to the minimum frame rate. Fixed: The output stream uses the specified frame rate. The value must be smaller than or equal to the frame rate of the input stream.
   Video Bitrate (Kbit/s)	Source-based: If the bitrate of the source stream is within the specified limits, the output bitrate is equal to the source bitrate. If it exceeds the upper limit, the output is capped at the maximum bitrate. If it falls below the lower limit, the output is set to the minimum bitrate. You can also specify a coefficient. Fixed: The output stream uses the specified bitrate. The following list describes the bitrate ranges for different resolutions: LD: 100 to 800 Kbit/s SD: 200 to 1,500 Kbit/s HD: 500 to 4,000 Kbit/s 2K: 2,000 to 8,000 Kbit/s 4K: 4,000 to 30,000 Kbit/s
   Video GOP	The GOP size indicates the interval between two I-frames. The GOP size of the output stream must be smaller than or equal to the GOP size of the input stream. To ensure low latency, the value cannot exceed 3 seconds.
   Audio Bitrate (Kbit/s)	This parameter is available when you set Template Type to Audio-only Transcoding. Unit: Kbit/s. Valid values: 8 to 1000.
   Profile	This parameter is available when you set Template Type to Audio-only Transcoding. LC-AAC: advanced audio coding with low complexity. The transcoding efficiency is high. HE-AAC: advanced audio coding with high efficiency. The sound effect of HE-AAC is better than that of LC-AAC when the audio bitrate is lower than 128 Kbit/s.
   Sampling Rate	This parameter is available when you set Template Type to Audio-only Transcoding. Valid values: 22050, 32000, 44100, 48000, and 96000.
   Sound Channels	This parameter is available when you set Template Type to Audio-only Transcoding. Valid values: 1 and 2.
   Transcoding Mode (Advanced Settings)	The quality-first and latency-first modes are supported. In the latency-first mode, low latency is ensured for the transcoded stream.
   Trigger Transcoding (Advanced Settings)	If you turn on the switch, transcoding is triggered only when a stream is pulled for the first time. If you turn off the switch, transcoding is triggered whenever a stream is ingested.
   Video Encryption (Advanced Settings)	After you turn on the switch, you can select Alibaba Cloud Proprietary Cryptography or DRM Encryption. Note DRM encryption is supported only in the China (Shanghai) and Singapore regions. Alibaba Cloud Proprietary Cryptography Videos can be generated only in the HLS and FLV formats. KMS CMK ID: Specify a customer master key (CMK) in Key Management Service (KMS). The region of the CMK must be the same as the region in which the live center resides. If you do not have a CMK, go to the KMS console to create one. For more information, see Purchase and enable a KMS instance. CMK Rotation Period: Enter an integer from 60 to 3,600. For more information, see Alibaba Cloud proprietary cryptography. DRM Encryption Before you enable this feature, you need to configure DRM encryption. For more information, see Configure DRM encryption. Videos in the HLS format can be encrypted by using Widevine and FairPlay DRM. To use FairPlay DRM, you must upload a FairPlay Streaming certificate that you obtain from Apple on the DRM Management page. For information about how to apply for a FairPlay Streaming certificate, see Apply for a FairPlay Streaming certificate.
   All SEI Passed-through (Advanced Settings)	If you enable this feature, all SEI messages are passed through.
   Source-based Keyframes (Advanced Settings)	If you enable this feature, the keyframes of the transcoded stream are the same as the keyframes of the source stream.
   Source-based PTS (Advanced Settings)	If you enable this feature, the presentation timestamp (PTS) of the transcoded stream is the same as the PTS of the source stream.

4. Click OK.

The parameter configuration of relevant API operations is complex. We recommend that you use the APIs in conjunction with the console, because the console provides resolution preview and supports automatically filling in the preset templates.

Procedure

1. Add a template for custom transcoding in the ApsaraVideo Live console.

2. Call the DescribeLiveStreamTranscodeInfo operation to query the template added. SDK for Java sample code:

        // Replace the placeholders with actual values.
        DefaultProfile profile = DefaultProfile.getProfile("<regionId>", "<ALIBABA_CLOUD_ACCESS_KEY_ID>", "<ALIBABA_CLOUD_ACCESS_KEY_SECRET>");
        IAcsClient client = new DefaultAcsClient(profile);
        DescribeLiveStreamTranscodeInfoRequest describeLiveStreamTranscodeInfoRequest=new DescribeLiveStreamTranscodeInfoRequest();
        describeLiveStreamTranscodeInfoRequest.setAppName("<AppName>");
        describeLiveStreamTranscodeInfoRequest.setDomainTranscodeName("<DomainName>");
        DescribeLiveStreamTranscodeInfoResponse describeLiveStreamTranscodeInfoResponse = null;
        try {
            describeLiveStreamTranscodeInfoResponse = client.getAcsResponse(describeLiveStreamTranscodeInfoRequest);
        } catch (ClientException e) {
            e.printStackTrace();
        }
        System.out.println(new Gson().toJson(describeLiveStreamTranscodeInfoResponse));

3. Call the AddCustomLiveStreamTranscode operation to add a custom transcoding configuration based on the domain name and application name.

        AddCustomLiveStreamTranscodeRequest addCustomLiveStreamTranscodeRequest=new AddCustomLiveStreamTranscodeRequest();
        addCustomLiveStreamTranscodeRequest.setDomain("<DomainName>");
        addCustomLiveStreamTranscodeRequest.setApp("<AppName>");
        /**
         * Configure transcoding parameters.
         */
        AddCustomLiveStreamTranscodeResponse addCustomLiveStreamTranscodeResponse = null;
        try {
            addCustomLiveStreamTranscodeResponse = client.getAcsResponse(addCustomLiveStreamTranscodeRequest);
        } catch (ClientException e) {
            e.printStackTrace();
        }
        System.out.println(new Gson().toJson(addCustomLiveStreamTranscodeResponse));