Intelligent Media Management:Video subtitle extraction

Prerequisites

• An AccessKey pair is created and obtained. For more information, see Create an AccessKey pair.

• Object Storage Service (OSS) is activated and a bucket is created. For more information, see Create a bucket.

• IMM is activated. For more information, see Activate IMM.

• A project is created in the IMM console. For more information, see Create a project.

  Note

  • You can call the CreateProject operation to create a project. For more information, see CreateProject.

  • You can call the ListProjects operation to list information of all projects in a region.

Step 1: Upload a file

Use the OSS console to upload a media file to a bucket that resides in the same region as your IMM project.

Step 2: Use IMM to extract subtitles from a video

Call the CreateMediaConvertTask operation to create a video subtitle extraction task.

The extraction process includes the following phases:

1. Subtitle format identification: Identifies the formats of subtitles embedded in the video file, including the SubRip Subtitle (SRT), Advanced SubStation Alpha (ASS), Web Video Text Tracks (WebVTT), and embedded subtitle stream formats.

2. Subtitle data extraction: Extracts subtitle text and its timestamps from the video file. This phase ensures that all subtitle content, including the speaker name, timestamps, and time format, are accurately captured.

3. Text processing: Performs the necessary processing or editing on the extracted subtitle text. During this phase, the system may remove redundant information, adjust formats, translate languages, and perform spelling and grammar proofreading.

4. Output and saving: Saves the processed subtitle text in a specified format, such as the SRT or ASS format, to facilitate usage, editing, or uploading to video platforms during subsequent operations.

Extract all subtitles from a video and convert them to the WebVTT format

• Subtitle format: WebVTT.

• Subtitle file output path: oss://test-bucket/video-demo/subtitle-%d.vtt

• Transcoding completion notification: a Simple Message Queue (formerly MNS) (SMQ) message, which is sent to an SMQ topic named "test-mns-topic".

For more information about the sample SDK, go to OpenAPI Explorer. The parameters in the example are automatically configured in OpenAPI Explorer. Before you debug the code, modify the parameters as needed.

Request parameters

{
  "ProjectName": "test-project",
  "Notification": {
    "MNS": {
      "TopicName": "test-mns-topic"
    }
  },
  "Sources": [
    {
      "URI": "oss://test-bucket/video-demo/test.mp4"
    }
  ],
  "Targets": [
    {
      "Subtitle": {
        "ExtractSubtitle": {
          "Format": "webvtt",
          "URI": "oss://test-bucket/video-demo/subtitle-{streamindex}.{autoext}"
        }
      }
    }
  ]
}

Extract all subtitles from a video and convert them to the SRT format

• Subtitle format: SRT.

• Subtitle file output path: oss://test-bucket/video-demo/subtitle-%d.srt

• Transcoding completion notification: an SMQ message, which is sent to an SMQ topic named "test-mns-topic".

For more information about the sample SDK, go to OpenAPI Explorer. The parameters in the example are automatically configured in OpenAPI Explorer. Before you debug the code, modify the parameters as needed.

Request parameters

{
  "ProjectName": "test-project",
  "Notification": {
    "MNS": {
      "TopicName": "test-mns-topic"
    }
  },
  "Sources": [
    {
      "URI": "oss://test-bucket/video-demo/test.mp4"
    }
  ],
  "Targets": [
    {
      "Subtitle": {
        "ExtractSubtitle": {
          "Format": "srt",
          "URI": "oss://test-bucket/video-demo/subtitle-{streamindex}.{autoext}"
        }
      }
    }
  ]
}