Alternate HLS audio rendition requirements
With HLS rendition groups, you can use the audio selector settings to indicate which alternate audio rendition you want MediaConvert to use. To be eligible for selection, your alternate audio renditions must conform to the following requirements:
-
The renditions must be included in
EXT-X-MEDIA
tags in the input parent manifest. -
The
EXT-X-MEDIA
tags must contain a unique combination of GROUP-ID, NAME, and LANGUAGE values.. -
Audio must be in one of the following supported audio codecs: AAC, Dolby Digital (AC3), Dolby Digital Plus (EAC3), or MP3.
-
The child manifest for your alternate audio rendition must be included in the parent manifest that you used for your Input file URL (FileInput)
When you specify audio selector settings to identify an alternate audio
rendition, the audio selector looks for a matching EXT-X-MEDIA
tag in
the parent manifest.
You can use one or more selector settings at a time. For example, given the
following EXT-X-MEDIA
tags, you can identify the audio rendition by the
name (RenditionName) or language (RenditionLangageCode) because these are both
unique values across the tags.
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="audio",CHANNELS="2",NAME="English",LANGUAGE="eng",DEFAULT=YES,AUTOSELECT=YES,URI="english_audio.m3u8"
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="audio",CHANNELS="2",NAME="Japanese",LANGUAGE="jpn",DEFAULT=NO,AUTOSELECT=NO,URI="japanese_audio.m3u8"
However, because the group ID (RenditionGroupID) is the same for both tags, you
can't use that alone to identify an audio rendition. You must use the group ID in
combination with another value from the EXT-X-MEDIA
tag to identify the
audio rendition that you want MediaConvert to use.
If you don't specify audio selector settings, the audio selector looks for audio that's muxed into the video segments. If the video segments don't contain audio, the audio selector uses the first alternate audio rendition from the input parent manifest.