Narrowband HD™ transcoding is a proprietary Alibaba Cloud technology that intelligently analyzes video content, including scenes, motion, and textures. It reduces video bitrates and lowers bandwidth costs without compromising visual quality. Narrowband HDTM 1.0 can reduce bitrates by 20% to 40% compared to standard transcoding. Narrowband HDTM 2.0 further reduces bitrates and provides lightweight video quality restoration and enhancement, delivering higher resolutions at lower bitrates than Narrowband HDTM 1.0.
Benefits
|
Benefit |
Narrowband HDTM 1.0 |
Narrowband HDTM 2.0 |
|
Narrowband: Reduces unnecessary bits. |
✔️ |
✔️ |
|
HD: Allocates bits to the most visually impactful areas. |
✔️ |
✔️ |
|
Softens areas less noticeable to the human eye, such as out-of-focus regions and minor details. |
✔️ |
✔️ |
|
Enhances details in focused areas and regular textures. |
❌ |
✔️ |
|
Repairs visually distracting artifacts, such as aliasing, flickering, and mosaic effects. |
❌ |
✔️ |
Billing
Video transcoding is a paid service. You are charged based on the specifications and duration of the output video. For more information, see Media transcoding billing.
Limitations
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Narrowband HDTM 1.0 and Narrowband HDTM 2.0 are supported in all regions. For the service regions supported by ApsaraVideo VOD, see Service regions.
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Narrowband HDTM 1.0 and Narrowband HDTM 2.0 transcoding can output video only in HLS and MP4 formats.
Usage
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The video parameters, such as resolution and bitrate, of Narrowband HDTM 1.0 transcoding templates are built-in and cannot be edited. The preset template parameters are as follows:
Definition
Bitrate range (Kbps)
Width (px)
LD - Narrowband HD 1.0
≤400
640
SD - Narrowband HD 1.0
≤800
848
HD - Narrowband HD 1.0
≤1500
1280
FHD - Narrowband HD 1.0
≤3000
1920
2K - Narrowband HD 1.0
≤4000
2048
4K - Narrowband HD 1.0
≤8000
3840
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Narrowband HDTM 2.0 transcoding is relatively slow. For testing, we recommend using a short video of less than three minutes.
How to use
Console
Step 1: Create a Narrowband HD™ template group
You must first create a Narrowband HD™ transcoding template group to use for transcoding jobs. For more information, see:
Step 2 (Optional): Create and associate a workflow
You can orchestrate various media processing tasks, such as transcoding, content review, and snapshot capture, into a specific sequence within a workflow. When you trigger the workflow during media upload or processing, the workflow automatically processes the media file according to the predefined tasks.
You can create a workflow, add a media transcoding node to it, and associate the node with the Narrowband HD™ transcoding template group created in the previous step. For more information, see Manage workflows.
Step 3: Start transcoding
Use the Narrowband HD™ transcoding template group or workflow that you created to transcode your video. You can trigger transcoding during or after media upload.
During upload
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Log on to the ApsaraVideo VOD console.
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In the left-side navigation pane, choose Media Files > Audio/Video, and then click Upload.
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Click Add Media. Configure parameters such as the upload method and storage location. Then, select Use Transcoding Template Group or Use Workflow and specify the transcoding template group or workflow that you created.
For more information about supported upload formats and parameter descriptions, see Upload media files in the console.
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After adding the audio or video files to be uploaded, click Upload.
After upload
This operation is typically used to re-transcode existing videos, apply standard encryption, or override watermark parameters.
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Log on to the ApsaraVideo VOD console.
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In the left-side navigation pane, choose Media Files > Audio/Video.
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On the Audio/Video page, find the media file you want to transcode and click Processing in the Actions column.
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In the Media Processing dialog box, select Use Transcoding Template Group or Use Workflow, and then specify the Narrowband HD™ transcoding template group or workflow that you created. For example, select Use Transcoding Template Group and select the desired template group, such as Test-NarrowbandHD, from the drop-down list.
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Click OK.
Step 4: View the result
After you start transcoding, you can use the following methods to view information such as the transcoding status and the URL of the transcoded video. You can use the video URL to play the transcoded video with ApsaraVideo Player or a third-party player.
If no accelerated domain name is configured in ApsaraVideo VOD, playing or downloading a video from its URL incurs outbound storage traffic fees. For more information, see Billing of outbound traffic from OSS.
Method 1: Console
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Log on to the ApsaraVideo VOD console.
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In the left-side navigation pane, choose Media Files > Audio/Video.
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On the Audio/Video page, view the status of the transcoded media file.
A status of Normal indicates that transcoding is successfully completed. For descriptions of other statuses, see Video statuses.
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Click Manage in the Actions column of the transcoded media file and click the Video URL tab.
Video streams and URLs are generated for the corresponding definitions of successfully transcoded media files.
In the list of video URLs, video streams transcoded with Narrowband HD™ are displayed as FHD - Narrowband HD 1.0 in the Definition column, are in MP4 format, and are listed separately from the source video.
Method 2: Event notifications
ApsaraVideo VOD supports event notifications through HTTP callbacks and Message Service (MNS). By configuring event notifications in advance, ApsaraVideo VOD notifies you when a media file is processed, for example, when an upload or transcoding is complete. You can retrieve information such as the transcoding job status and the transcoded video URL from the callback results. For configuration instructions, see Event notifications.
The following events are related to transcoding:
API
Usage
To call API operations, see API overview. We recommend that you use OpenAPI Explorer for debugging. You can run ApsaraVideo VOD API operations directly in OpenAPI Explorer without calculating signatures. After a successful call, OpenAPI Explorer automatically generates sample code for the SDK.
Step 1: Create a Narrowband HD™ template group
You must first create a Narrowband HD™ transcoding template group to use when you initiate transcoding jobs.
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Call the AddTranscodeTemplateGroup operation. Specify the parameters for Narrowband HD™ in the
Definitionparameter ofTranscodeTemplateto create a Narrowband HD™ transcoding template group.
Step 2 (Optional): Create and associate a workflow
You can orchestrate various media processing tasks, such as transcoding, content review, and snapshot capture, into a specific sequence within a workflow. When you trigger the workflow during media upload or processing, the media file is automatically processed according to the predefined series of tasks.
You can currently create workflows only in the ApsaraVideo VOD console. For instructions, see Manage workflows.
Step 3: Start transcoding
Use the Narrowband HD™ transcoding template group or workflow that you created to transcode your video. You can trigger transcoding during or after media upload.
During upload
The CreateUploadVideo operation is used only to obtain upload URLs and credentials and to create basic media asset information. It does not upload files. You must implement your own upload logic. For a complete example of uploading files by using API operations, see Upload media files by using the ApsaraVideo VOD API.
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When you call the CreateUploadVideo or UploadMediaByURL operation to upload media files, specify the Narrowband HD™ transcoding template group ID in the
TemplateGroupIdparameter, or specify the ID of a workflow that includes a media transcoding node in theWorkflowIdparameter. After the media files are uploaded, ApsaraVideo VOD automatically transcodes them based on the specified template group or workflow.
After upload
This operation is typically used to re-transcode existing videos, apply standard encryption, or override watermark parameters.
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Call the SubmitTranscodeJobs operation and specify the Narrowband HD™ transcoding template group ID in the
TemplateGroupIdparameter, or call the SubmitWorkflowJob operation and specify the ID of a workflow that includes a media transcoding node in theWorkflowIdparameter. After you manually initiate transcoding, ApsaraVideo VOD immediately transcodes the media files based on your specified template group or workflow.
Step 4: View the result
After you start transcoding, you can use the following methods to view information such as the transcoding status and the URL of the transcoded video. You can use the video URL to play the transcoded video with ApsaraVideo Player or a third-party player.
If no accelerated domain name is configured in ApsaraVideo VOD, playing or downloading a video from its URL incurs outbound storage traffic fees. For more information, see Billing of outbound traffic from OSS.
Method 1: API
The SubmitTranscodeJobs operation returns a TranscodeTaskId for the transcoding job. You can then call the GetTranscodeTask operation to query the execution status and output video URL of the specified transcoding job.
Method 2: Event notifications
ApsaraVideo VOD supports event notifications through HTTP callbacks and MNS. After you configure event notifications, ApsaraVideo VOD notifies you when a media file is processed, for example, when an upload or transcoding is complete. You can retrieve information such as the transcoding job status and the transcoded video URL from the callback results. For configuration instructions, see Event notifications.
The following events are related to transcoding: