Enable and view a clapperboard with extracted metadata (preview)

A clapperboard insight is used to detect clapperboard instances and information written on each. For example, head or tail (the board is upside-down), production, roll, scene, take, date, etc. The clapperboard's extracted metadata is most useful to customers involved in the movie post-production process.

When the movie is being edited, a clapperboard is removed from the scene; however, the information that was written on the clapperboard is important. Azure Video Indexer extracts the data from clapperboards, preserves, and presents the metadata.

This article shows how to enable the post-production insight and view clapperboard instances with extracted metadata.

View the insight

View post-production insights

In order to set the indexing process to include the slate metadata, select the Video + audio indexing -> Advanced presets.

After the file has been uploaded and indexed, if you want to view the timeline of the insight, select the Post-production checkmark from the list of insights.

Clapperboards

Clapperboards contain fields with titles (for example, production, roll, scene, take) and values (content) associated with each title.

For example, take this clapperboard:

In the following example the board contains the following fields:

title	content
camera	COD
date	FILTER (in this case the board contains no date)
director	John
production	Prod name
scene	1
take	99

View the insight

To see the instances on the website, select Insights and scroll to Clapperboards. You can hover over each clapperboard, or unfold Show/Hide clapperboard info and see the metadata:

View the timeline

If you checked the Post-production insight, You can also find the clapperboard instance and its timeline (includes time, fields' values) on the Timeline tab.

View JSON

To display the JSON file:

1. Select Download and then Insights (JSON).
2. Copy the clapperboard element, under insights, and paste it into your Online JSON Viewer.

The following table describes fields found in json:

Name	Description
id	The clapperboard ID.
thumbnailId	The ID of the thumbnail.
isHeadSlate	The value stands for head or tail (the board is upside-down) of the clapper board: true or false.
fields	The fields found in the clapper board; also each field's name and value.
instances	A list of time ranges where this element appeared.

Clapperboard limitations

The values may not always be correctly identified by the detection algorithm. Here are some limitations:

• The titles of the fields appearing on the clapper board are optimized to identify the most popular fields appearing on top of clapper boards.
• Handwritten text or digital digits may not be correctly identified by the fields detection algorithm.
• The algorithm is optimized to identify fields' categories that appear horizontally.
• The clapperboard may not be detected if the frame is blurred or that the text written on it can't be identified by the human eye.
• Empty fields’ values may lead to to wrong fields categories.

Next steps

• Slate detection overview
• How to enable and view digital patterns with color bars.
• How to enable and view textless slate with matched scene.