Animated character detection (preview)

Azure Media Services Video Indexer supports detection, grouping, and recognition of characters in animated content via integration with Cognitive Services custom vision. This functionality is available both through the portal and through the API.

After uploading an animated video with a specific animation model, Video Indexer extracts keyframes, detects animated characters in these frames, groups similar character, and chooses the best sample. Then, it sends the grouped characters to Custom Vision that identifies characters based on the models it was trained on.

Before you start training your model, the characters are detected namelessly. As you add names and train the model the Video Indexer will recognize the characters and name them accordingly.

Flow diagram

The following diagram demonstrates the flow of the animated character detection process.

Flow diagram


Depending on a type of your Video Indexer account, different feature sets are available. For information on how to connect your account to Azure, see Create a Video Indexer account connected to Azure.

  • Trial account: Video Indexer uses an internal Custom Vision account to create model and connect it to your Video Indexer account.
  • Paid account: you connect your Custom Vision account to your Video Indexer account (if you don’t already have one, you need to create an account first).

Trial vs. paid

Functionality Trial Paid
Custom Vision account Managed behind the scenes by Video Indexer. Your Custom Vision account is connected to Video Indexer.
Number of animation models One Up to 100 models per account (Custom Vision limitation).
Training the model Video Indexer trains the model for new characters additional examples of existing characters. The account owner trains the model when they are ready to make changes.
Advanced options in Custom Vision No access to the Custom Vision portal. You can adjust the models yourself in the Custom Vision portal.

Use the animated character detection with portal

This section describes the steps you need to take to start using the animated character detection model.

Since in the trial accounts the Custom Vision integration is managed by Video Indexer, you can start creating and using the animated characters model and skip the following section ("Connect your Custom Vision account").

Connect your Custom Vision account (paid accounts only)

If you own a Video Indexer paid account, you need to connect a Custom Vision account first. If you don't have a Custom Vision account already, please create one. For more information, see Custom Vision.


Both accounts need to be in the same region. The Custom Vision integration is currently not supported in the Japan region.

Connect a Custom Vision account with API

Follow these steps to connect you Custom Vision account to Video Indexer, or to change the Custom Vision account that is currently connected to Video Indexer:

  1. Browse to and login.

  2. Copy the following keys:

    • Training key (for the training resource)
    • Prediction key (for the prediction resource)
    • Endpoint
    • Prediction resource ID


    To provide all the keys you need to have two separate resources in Custom Vision, one for training and one for prediction.

  3. Browse and sign in to the Video Indexer.

  4. Click on the question mark on the top-right corner of the page and choose API Reference.

  5. Make sure you are subscribed to API Management by clicking Products tab. If you have an API connected you can continue to the next step, otherwise, subscribe.

  6. On the developer portal, click the Complete API Reference and browse to Operations.

  7. Select Connect Custom Vision Account (PREVIEW) and click Try it.

  8. Fill in the required fields as well as the access token and click Send.

    For more information about how to get the Video Indexer access token go to the developer portal, and see the relevant documentation.

  9. Once the call return 200 OK response, your account is connected.

  10. To verify your connection by browse to the Video Indexer) portal:

  11. Click on the Content model customization button in the top-right corner.

  12. Go to the Animated characters tab.

  13. Once you click on Manage models in Custom Vision”**, you will be transferred to the Custom Vision account you just connected.


Currently, only models that were created via Video Indexer are supported. Models that are created through Custom Vision will not be available. In addition, the best practice is to edit models that were created through Video Indexer only through the Video Indexer platform, since changes made through Custom Vision may cause unintended results.

Create an animated characters model

  1. Browse to the Video Indexer website and sign in.

  2. Click on the content model customization button on the top-right corner of the page.

    Content model customization

  3. Go to the Animated characters tab in the model customization section.

  4. Click on Add model.

  5. Name you model and click enter to save the name.


The best practice is to have one custom vision model for each animated series.

Index a video with an animated model

  1. Click on the Upload button from the top menu.
  2. Choose a video to upload (from a file or a URL).
  3. Click on Advanced options.
  4. Under People / Animated characters choose Animation models.
  5. If you have one model it will be chosen automatically, and if you have multiple models you can choose the relevant one out of the dropdown menu.
  6. Click on upload.
  7. Once the video is indexed, you will see the detected characters in the Animated characters section in the Insights pane.


Before tagging and training the model, all animated characters will be named “Unknown #X”. After you train the model they will also be recognized.

Customize the animated characters models

  1. Tag and train the model.

    1. Tag the detected character by editing its name. Once a character is trained into the model, it will be recognized it the next video indexed with that model.

    2. To tag an animated character in your video, go to the Insights tab and click on the Edit button on the top-right corner of the window.

    3. In the Insights pane, click on any of the detected animated characters and change their names from "Unknown #X" (or the name that was previously assigned to the character).

    4. After typing in the new name, click on the check icon next to the new name. This saves the new name in the model in Video Indexer.

    5. After you finished editing all names you want, you need to train the model.

      Open the customization page and click on the Animated characters tab and then click on the Train button to train your model.

      If you have a paid account, you can click the Manage models in Customer Vision link (as shown below). You will then be forwarded to the model's page in Custom Vision.

      Content model customization

    6. Once trained, any video that will be indexed or reindexed with that model will recognize the trained characters. Paid accounts that have access to their Custom Vision account can see the models and tagged images there. Learn more about improving your classifier in Custom Vision.

  2. Delete an animated character.

    1. To delete an animated character in your video insights, go to the Insights tab and click on the Edit button on the top-right corner of the window.
    2. Choose the animated character and then click on the Delete button under their name.


    This will delete the insight from this video but will not affect the model.

  3. Delete a model.

    1. Click on the Content model customization button on the top menu and go to the Animated characters tab.
    2. Click on the ellipsis icon to the right of the model you wish to delete and then on the delete button.
    • Paid account: the model will be disconnected from Video Indexer and you will not be able to reconnect it.

    • Trial account: the model will be deleted from Customs vision as well.


      In a trial account, you only have one model you can use. After you delete it, you can’t train other models.

Use the animated character detection with API

  1. Connect a Custom Vision account.

    If you own a Video Indexer paid account, you need to connect a Custom Vision account first.
    If you don’t have a Custom Vision account already, please create one. For more information, see Custom Vision.

    Connect your Custom Vision account using API.

  2. Create an animated characters model.

    Use the create animation model API.

  3. Index or re-index a video.

    Use the re-indexing API.

  4. Customize the animated characters models.

    Use the train animation model API.

View the output

See the animated characters in the generated JSON file.

"animatedCharacters": [
    "videoId": "e867214582",
    "confidence": 0,
    "thumbnailId": "00000000-0000-0000-0000-000000000000",
    "seenDuration": 201.5,
    "seenDurationRatio": 0.3175,
    "isKnownCharacter": true,
    "id": 4,
    "name": "Bunny",
    "appearances": [
            "startTime": "0:00:52.333",
            "endTime": "0:02:02.6",
            "startSeconds": 52.3,
            "endSeconds": 122.6
            "startTime": "0:02:40.633",
            "endTime": "0:03:16.6",
            "startSeconds": 160.6,
            "endSeconds": 196.6


  • Currently, the "animation identification" capability is not supported in East-Asia region.
  • Characters that appear to be small or far in the video may not be identified properly if the video's quality is poor.
  • The recommendation is to use a model per set of animated characters (for example per an animated series).

Next steps

Video Indexer overview