ApsaraVideo Live:Time shifting

Configure the time shifting feature

// This file is auto-generated. Do not edit.
package com.aliyun.sample;

import com.aliyun.tea.*;

public class Sample {

    /**
     * description

Use the time shifting feature

After you configure time shifting, ApsaraVideo Live saves the TS segment files of the live stream. The client can then send a time-shifted playback request to play back the live content.

The following example shows a time-shifted playback request:

http://<DomainName>/<AppName>/<StreamName.m3u8>?aliyunols=on&lhs_offset_unix_s_0=300&auth_key=3sdda******

As shown in the example, the time shifting request is similar to a live streaming URL for an M3U8 file but includes two additional parameters. aliyunols=on is a fixed field, and lhs_offset_unix_s_0=300 indicates a rewind of 300 seconds.

In this example, the live content is rewound by 300 seconds. When you play back time-shifted content, you can use the lhs_offset_unix_s_0 parameter to set the playback time. The parameter format is lhs_{type}_{format}_{unit}_{zone}.

The following table describes the variables in the parameter.

The following examples show the time shifting parameters:

• lhs_start_human_s_8=20170809200010

• lhs_start_unix_s_0=1502280113

• lhs_end_human_s_8=20170809200010

• lhs_vodend_unix_s_0=1502280113

• lhs_offset_unix_ms_0=1800000 (rewind by 30 minutes)

If you do not know the specific start and end times for your business, you can query the time shifting timeline to obtain them.

The following example shows how to query the time shifting timeline:

// Replace the values in angle brackets (<>) with your actual values.
http://<DomainName>/openapi/timeline/query?aliyunols=on&app=<AppName>&stream=<StreamName>&format=ts&lhs_start_unix_s_0=<StartTime>&lhs_end_unix_s_0=<endTime>&auth_key=<auth_key>

The following is an example:

The following example shows a sample response:

{
  "retCode": 0,
  "description": "success",
  "content": {
    "current": 1514269063,
    "timeline": [
      {
        "start": 1514269054,
        "end": 1514269058
      }
    ]
  }
}

Play back transcoded streams with time shifting

You can use the time shifting feature with the transcoding feature to play back transcoded streams. To play back transcoded streams with time shifting, you must first configure transcoding. For more information about how to configure transcoding, see Live stream transcoding.

This section assumes that you have completed the transcoding configuration.

When you configure time shifting, you must also generate time-shifted data for transcoded streams. The following example shows the sample code:

// Specifies whether to ignore the corresponding transcoded stream when generating time-shifted data. Valid values: true and false. Default value: true.
openLiveShiftRequest.setIgnoreTranscode("<false>");

To enable time-shifted playback, Add Time-shifting Parameters to the transcoded stream URL.

The following example shows a playback URL:

http://<DomainName>/<AppName>/<StreamName_TranscodingTemplateID.m3u8>?aliyunols=on&lhs_offset_unix_s_0=300&auth_key=3sdda******

Play back encapsulated streams with time shifting

To play back encapsulated streams with time shifting, use the Time Shifting feature in conjunction with the Encapsulation feature.

If you are not familiar with the live stream encapsulation feature, see Live stream encapsulation.

This section assumes that you have completed the live stream encapsulation configuration.

To play back encapsulated streams with time shifting, you do not need to modify the time shifting configuration. You can simply add the time shifting parameters to the encapsulated stream URL.

The following example shows a playback URL:

http://<DomainName>/<AppName>/<StreamName-ContainerFormat.m3u8>?aliyunols=on&lhs_offset_unix_s_0=300&auth_key=3sdda******

References

For more information about the APIs for time shifting, see Time shifting.