Creating audio ABR streaming outputs - MediaConvert

Creating audio ABR streaming outputs

For each audio output that you include in your output group, AWS Elemental MediaConvert creates one audio rendition, or set of segmented video files. The most common reason to include multiple audio renditions is to provide multiple language options. If you provide only one language, you probably need only one audio output.

Note

For AAC streaming outputs, the initial segment is longer in duration than the others. This is because, with AAC, the initial segment must contain silent AAC pre-roll samples before the audible part of the segment. MediaConvert accounts for these extra samples in the timestamps, so the audio plays back correctly.

To create and set up audio ABR streaming outputs

  1. Create an output for your first audio track. Usually an audio track corresponds to one language.

    Note

    If you are working in a CMAF output group, skip this step. The first audio output is created for you.

    1. In the Job pane, choose the output group that you're working in.

    2. In the Outputs pane, choose Add output.

    3. Choose the output that you just created.

    4. If your output includes a group of video settings by default, choose Remove video to delete it. This leaves the Audio 1 group of settings displayed.

  2. In the Output settings pane, for Name modifier, enter a value.

    AWS Elemental MediaConvert appends the name modifier to the file names that it assigns to the files that it creates for this output. Enter a name modifier that will make it easy to identify which files came from which output, such as -audio-english.

  3. If one of the predefined groups of settings listed under Preset is suitable for your workflow, choose it from the list. If you use a preset, skip the next step of this procedure.

  4. Specify your audio settings as follows:

    1. In the Output settings section, specify values for any remaining general settings. For more information about individual settings, choose the Info link next to each setting.

    2. Under Stream settings, for Audio source, choose one of the audio selectors that you created in Step 2: Create input selectors for video, audio, and captions.

    3. In the Stream settings section, specify values for audio encoding. For more information about individual settings, choose the Info link next to each setting.

  5. If you have additional audio assets to include in the ABR streaming package, create an output for each of them as follows:

    1. In the Job pane, choose the output group that you're working in.

    2. In the Outputs pane, choose Add output.

    3. Choose the output that you just created.

    4. If your output includes a group of video settings by default, choose Remove video to delete it. This leaves the Audio 1 group of settings displayed.

    5. Set up the output as described in steps 2 through 4 of this procedure.