Using Dolby Atmos encoding with AWS Elemental MediaConvert - MediaConvert

Using Dolby Atmos encoding with AWS Elemental MediaConvert

AWS Elemental MediaConvert can encode Dolby Digital Plus with Atmos channel-based, immersive audio, Audio Descriptive Model Broadcast WAV files, or Dolby Atmos Master File.

Note

Understanding Dolby Atmos is required prerequisite knowledge for using this feature. Your input audio channels must already be set up according the Dolby Atmos standard you are using as input. For more information about Dolby Atmos, see the Dolby online documentation.

Input File Requirements for Dolby Atmos Encoding

Feature Restrictions for Dolby Atmos Encoding

Note the following restrictions in the AWS Elemental MediaConvert implementation of Dolby Atmos encoding:

  • Channel-based immersive: AWS Elemental MediaConvert supports channel-based immersive (CBI) content.

  • Dolby Atmos Master File (DAMF): AWS Elemental MediaConvert supports Dolby Atmos master file (DAMF). This is a collection of 3 files with the extensions, .atmos, .atmos.metadata, and .atmos.audio

  • Audio Descriptive Model Broadcast WAV Format (ADM BWF): AWS Elemental MediaConvert supports ADM BWF. It is a single broadcast WAV file contains header data with the .atmos and .atmos.metadata information.

  • Output codec: You can create Dolby Atmos audio outputs encoded with only the Dolby Digital Plus (EAC3) codec.

  • Output containers: For file outputs, you can create Dolby Atmos audio in only in one of the video containers that supports Dolby Digital Plus: MPEG-4, MPEG-2 Transport Stream, or QuickTime.

  • Output packages: For adaptive bitrate (ABR) outputs, you can create Dolby Atmos audio in any of the AWS Elemental MediaConvert output group types: CMAF, Apple HLS, DASH ISO, or Microsoft Smooth Streaming.

Setting up a job for Dolby Atmos encoding

To encode 9.1.6 audio Dolby Atmos objects, provide 16 input channels of PCM audio, either in individual .wav files or as tracks in a single container.

If you provide input audio as individual .wav files, you specify them in order in your input. You specify them as Audio selector 1, Audio selector 2, and so on, up to Audio selector 16. If you provide your audio as a single file containing 16 tracks, you specify the file in your input as Audio selector 1, and then you specify the tracks individually within that audio selector.

Important

Regardless of whether they are in separate files or a single file, you must set up the channels in the following order: L, R, C, LFE, Ls, Rs, Lrs, Rrs, Lw, Rw, Ltf, Rtf, Ltm, Rtm, Ltr, Rtr.

For more details about setting up your job for Dolby Atmos encoding, see one of the following procedures:

Procedure with separate audio input files

Procedure with a single audio input file

To set up a Dolby Atmos job, with audio inputs as 16 individual .wav files

  1. Open the MediaConvert console at https://console.aws.amazon.com/mediaconvert.

  2. Choose Create job.

  3. Set up your input video as described in Setting up a job in AWS Elemental MediaConvert.

  4. Set up your input audio selectors as follows:

    1. On the Create job page, in the Job pane on the left, choose Input.

    2. On the right, in the Audio selectors section, under Audio selector 1, choose External file.

    3. For External file, provide the path and file name to the .wav file for your first channel. For Audio selector 1, this channel must be L.

      Important

      You must set up the channels in the following order: L, R, C, LFE, Ls, Rs, Lrs, Rrs, Lw, Rw, Ltf, Rtf, Ltm, Rtm, Ltr, Rtr.

      That is, if your input audio is in separate .wav files, Audio selector 1 must point to the L channel, Audio selector 2 must point to the R channel, and so on.

    4. At the top of the Audio selectors section, choose Add audio selector to create Audio selector 2.

    5. Under Audio selector 2, choose External file.

    6. Specify the path and file name to the .wav file for your second channel. For Audio selector 2, this channel must be R.

    7. Repeat the steps to create an audio selector for the rest of your 16 channels. Choose the following channels for each selector:

      • Audio selector 3: C

      • Audio selector 4: LFE

      • Audio selector 5: Ls

      • Audio selector 6: Rs

      • Audio selector 7: Lrs

      • Audio selector 8: Rrs

      • Audio selector 9: Lw

      • Audio selector 10: Rw

      • Audio selector 11: Ltf

      • Audio selector 12: Rtf

      • Audio selector 13: Ltm

      • Audio selector 14: Rtm

      • Audio selector 15: Ltr

      • Audio selector 16: Rtr

  5. Create an input Audio selector group as follows:

    1. In the Audio selector groups section, choose Add audio selector group.

    2. For Group name, enter a descriptive name, such as Dolby Atmos Audio Group.

    3. For Select audio selectors, choose each audio selector that you created earlier in this procedure. Choose them in order, starting with Audio selector 1.

  6. Set up your output groups, outputs, and video output selectors as described in Setting up a job in AWS Elemental MediaConvert and Creating outputs with AWS Elemental MediaConvert. Choose supported containers as listed in Feature Restrictions for Dolby Atmos Encoding.

  7. Create audio output selectors as described in Setting up a job in AWS Elemental MediaConvert and Creating outputs with AWS Elemental MediaConvert.

    Set them up as follows:

    1. In the Job pane on the left, choose an output that includes audio.

    2. In the Encoding settings section, choose Audio 1.

    3. For Audio codec, choose Dolby Digital Plus JOC (Atmos).

      For Audio source, choose the audio selector group that you created earlier in this procedure, such as Dolby Atmos Audio Group.

    4. For the audio encoding settings, choose values that are suitable for your workflow. For more information, see the Dolby documentation for the Dolby Digital Plus Atmos encoding library.

      Note

      AWS Elemental MediaConvert automatically performs audio normalization on Dolby Digital Plus Atmos outputs. Therefore, there is no Dialnorm setting under audio encoding settings.

To set up a Dolby Atmos job, with audio input as a single file with 16 tracks

  1. Open the MediaConvert console at https://console.aws.amazon.com/mediaconvert.

  2. Choose Create job.

  3. Set up your input video as described in Setting up a job in AWS Elemental MediaConvert.

  4. Set up your input audio selectors as follows:

    1. On the Create job page, in the Job pane on the left, choose Input.

    2. On the right, in the Audio selectors section, under Audio selector 1, choose External file.

    3. For External file, provide the path and file name to the .wav file.

    4. For Selector type, choose Track.

    5. For Tracks, list your 16 PCM mono tracks in a comma-separated list. Specify them in the following order: L, R, C, LFE, Ls, Rs, Lrs, Rrs, Lw, Rw, Ltf, Rtf, Ltm, Rtm, Ltr, Rtr.

      • If the tracks of your input audio file are already in that order, then list them that way: 1, 2, 3, … 16.

      • If the tracks of your input audio file are in a different order, list them according to the specified order. For example, if your L channel is in track 3, then list 3 first.

  5. Set up your output groups, outputs, and video output selectors as described in Setting up a job in AWS Elemental MediaConvert and Creating outputs with AWS Elemental MediaConvert. Choose supported containers as listed in Feature Restrictions for Dolby Atmos Encoding.

  6. Create audio output selectors as described in Setting up a job in AWS Elemental MediaConvert and Creating outputs with AWS Elemental MediaConvert.

    Set them up as follows:

    1. In the Job pane on the left, choose an output that includes audio.

    2. In the Encoding settings section, choose Audio 1.

    3. For Audio codec, choose Dolby Digital Plus JOC (Atmos).

      For Audio source, keep the default Audio selector 1.

    4. For the audio encoding settings, choose values that are suitable for your workflow. For more information, see the Dolby documentation for the Dolby Digital Plus Atmos encoding library.

      Note

      AWS Elemental MediaConvert automatically performs audio normalization on Dolby Digital Plus Atmos outputs. Therefore, there is no Dialnorm setting under audio encoding settings.