Configuring color space handling in each output

Note

This section assumes that you are familiar with creating or editing a channel, as described in Creating a channel from scratch.

This section describes how to set up each output in the MediaLive channel for the desired color space handling — passthrough or conversion. You can set up each output in a different way.

Follow these steps for each output in the channel.

Configure enhanced VQ mode

You must decide if you should enable enhanced VQ mode in the MediaLive output. This mode applies only to outputs that use H.264.

1. In the following table, find the planned handling in the first column, then read across to identify the action to take.

2. To enable enhanced VQ mode, see Setting up enhanced VQ mode.

Planned handling	Details	Action
Pass through	You already plan to enable enhanced VQ to improve the video quality.	Enable the mode.
Convert to SDR	The inputs contain both SDR and HDR content.	You must enable the mode.
Convert to SDR	The inputs contain only SDR content. For example, all the inputs are Rec. 709, and you want to convert the content to Rec. 601.	Enabling the mode is optional.
Any conversion	There is no HDR10 or HLG in any of the inputs.	Enabling the mode is optional.
Any conversion	You already plan to enable enhanced VQ to improve the video quality.	Enable the mode.

Prepare 3D LUT files

Perform these steps if you plan to convert the color space in a MediaLive output, and you want to use 3D LUT files for that conversion. You must obtain the 3D LUT files and store them in an accessible location.

1. Read MediaLive Support for processing with 3D LUT files for rules and requirements.

2. Identify the conversion combinations that you want to perform across all outputs in the channel. You can perform a maximum of 8 conversion combinations, because you can specify a maximum of 8 files.

3. Obtain the 3D LUT file for each combination. For files for HDR sources, make sure that you obtain the file that matches the maximum luminance of the source.

   Make sure that you know which source/output combination each 3D LUT file handles. There is no metadata in the files that lets MediaLive discover the combination. Instead, when MediaLive needs to choose a file, it reads the information that you specify when you configure the channel (in the next step).

4. Store the files in one or more buckets in Amazon S3. Make a note of the URLs for the files you want to use in this channel. Make sure that MediaLive has access to the Amazon S3 bucket or buckets.

Example

For example, you might have sources in Rec. 601, Rec. 709, and HDR10. You might want to convert the HDR10 sources to Rec. 709 in one output, and you might want to convert the SDR sources to HDR10 in another output. The following table summarizes your intentions.

Source	Rec. 709 output	HDR10 output
Rec. 601	Convert using standard mechanism	Convert using 3D LUT file
Rec. 709	No conversion	Convert using 3D LUT file
HDR10	Convert using 3D LUT file	No conversion

Therefore you need to provide three files:

• Rec. 601 to HDR10

• Rec. 709 to HDR10

• HDR10 to Rec. 709

Note that when there is no conversion, you shouldn't provide a file. MediaLive doesn't support handling that retains the source color space and only changes the color mapping. MediaLive would never use that file.

Note also that you decided not to provide a file to convert Rec. 601 to Rec. 709 because the difference in the output is minimal. MediaLive will convert the Rec. 601 source to Rec. 709, but it will do so using the standard mechanism.

Configure the channel to use 3D LUT files

Perform these steps if you plan to convert the color space in a MediaLive output, and you want to use 3D LUT files for that conversion. You must configure MediaLive to use those files.

1. On the Create channel page, in the General settings section, select Color Correction Settings. Slide the Enable Color correction settings field.

2. Choose Add global color corrections up to 8 times. In each line, enter the following information:

   • The URL for the 3D LUT file.

   • The input (source) color space that this file handles.

   • The output color space that this file handles.

Runtime handling

When you start the channel, MediaLive will use the 3D LUT files as follows:

• MediaLive reads the color space metadata in each source video frame. For example, for one frame, the metadata might specify that the color space is Rec. 601.

• It reads the color space you have configured for each output. For example, the video output might be set up for conversion to HDR10.

• MediaLive reads the information you configured about each file and finds the first file that matches the source and output.

  If the source and output are the same (for example, Rec. 601 source and Rec. 601 output), MediaLive doesn't look for a file. It always passes through the color space.

  If there is more than one 3D LUT file with the same input and output specified, MediaLive uses the first file it encounters.

• MediaLive uses that file to convert that combination of source and output.

• If there is no file for this combination, MediaLive performs the conversion using the standard mechanism (that is, without using 3D LUT color mapping).

Setting up for passthrough

You can set up to pass through the source color space in one or more MediaLive outputs. The key fields to set are Color space and Color metadata.

1. On the Create channel page, in the Output groups section, choose the output that contains the video. Display the Stream settings section, and choose the Video section.

2. For Codec settings, choose a codec. For information about the color spaces that each codec supports, see Output requirements.

3. Choose Codec details. More fields appear. Choose Additional settings. More fields appear.

   In Color metadata, choose Insert or Ignore to specify how you want to handle the color space metadata.

4. Choose Color space. The Color space settings field appears.

   Choose Color space passthrough. (Or choose Don't include, which is equivalent to Color space passthrough.)

Setting up to convert

You can set up to convert the color space in one or more MediaLive outputs. You must set up several fields, each in a specific way.

1. On the Create channel page, in the Output groups section, select the output that contains the video. Display the Stream settings section, and choose the Video section.

2. Complete the Width and Height fields to specify a valid resolution. Make a note of whether you are specifying an SD, an HD, or a UHD resolution.

3. In Codec settings, choose a codec. For information about the color spaces that each codec supports, see Output requirements.

4. Choose Codec details. More fields appear. Set the Profile, Tier, and Level fields, if they appear for the codec that you chose:

   • If the resolution is SD, enter values that suit your requirements.

   • If the resolution is an HD or UHD resolution, set the tier and level to suit your requirements, and set the profile as follows:

     • If the output color space will be an HDR color space, you must choose one of the profiles that has 10BIT in the name.

     • If the output color space will be an SDR color space, you can choose any profile.

5. Choose Color space. The Color space settings field appears.

   Set the field to the color space to convert to.

   If you choose HDR10, the Max CLL and Max FALL fields appear. Complete these fields to set the display metadata for the HDR10 output video.

6. Go back to Codec details and choose Additional settings. More fields appear, including Color metadata.

   In Color metadata, choose Insert or Ignore to specify how you want to handle the color space metadata. Typically, you omit it only if you know that the downstream system can't handle it properly.