Perform Content Analysis Using Dolby Vision™ Content Mapping

Once the HDR track is created, you are ready to analyze the shots of the sequence using Dolby Vision technology.

This analysis, also known as Level 1 Analysis Metadata for Dolby Vision, finds the minimal, maximal, and average luminance values of the content needed to create the HDR/SDR result for the target display, which can be previewed using the eCMU or the iCMU.

When you are asked to deliver L1 metadata, it means that you must perform a content analysis of the shots in the sequence.

To create L1 metadata for a shot:

1. Create the HDR track.

2. In the Effects environment, display the HDR track.

   Change track with the Track and Version Selection box on the left, above the HDR Mode section.

3. Select the HDR shot.

4. Select a Target Display.

   The results of the analysis are biased by the Mastering display. You must always perform an analysis for the 100-nit Rec. 709 display. This is a requirement for any Dolby Vision XML deliverable.

5. Set Analysis Scope to Current Shot.

6. Click Analyze.

   Once the analysis completes, the HDR indicator on the shot turns white to indicate a completed analysis. The Analysis Result shows the Minimal, Maximal, and Average luminance values.

You can set the scope of the analysis with the Analysis Scope box:

• Current Frame: Use this option if your content has similar properties.
• Current Shot: All visible frames of the current shots (that is, excluding heads/tails) are used for analysis.
• Selected Shots: Selected Storyboard shots are used for the analysis and resulting data is saved on a shot basis. Since the analysis may take time, a progress dialog box is displayed.
• All Shots: All shots on the HDR track are used for the analysis and resulting data is saved on a shot basis. Since the analysis may take time, a progress dialog box is displayed.
• Blend Shots: Selected shots are analyzed as a single shot and the analysis result is used for selected shot. Useful for content sharing image characteristic like multiple shots from the same content with VFX element separating the parts. In this use case, you want the analysis to have the same value to avoid tone mapping 'popping'.

If you encounter invalidation notifications:

• Keep Analysis option removes invalidation notifications. See About HDR FX invalidation for more details.

To discard the results of the analysis:

1. Select the shots and click Reset.

The analysis is very simple, but there are some limitations:

• Dolby Vision CMv2.9 and CMv4.0 have different analyses. Changing version requires you to perform an analysis if none exist for that version.
• Dolby Vision CMv2.9 analysis is based on the selected Mastering Display. If you change the active Mastering Display after analysis a shot, the HDR FX appears yellow to warn you that the analysis is no longer valid. When this happens, you must analyze the shot again.
• Dolby VisionCMv4.0 analysis remains valid even if you change Mastering Display.
• Creative Trims are not available for shots without an analysis.
• The analysis cannot be animated nor edited in the Animation Editor.

Working with Letterbox and Pillarbox

If you are working with shots containing contains letterbox / pillarbox, you must exclude those areas from the analysis. Use the Active Image Area to do just this: this ensures the analysis and the trims only include relevant pixels.

• Ratio: By default, the Active Image Area is set as the sequence image ratio. Select the ratio from the drop-down or enter a custom ratio value based on your content before analyzing the content and applying the trims. An extended list of aspect ratios has been added to the drop-down list: 16:9, 4:3, 1.37, 1.66, 1.85, 1.89, 2.35, 2.39, 2.40
• Colour: Show the ratio outline
• Colour Pot: The colour of the outline
• Style: The outline styles