Description:
HLS-VOD-Stream contains several audio tracks, being marked with same language tag but different name tag.
https://devstreaming-cdn.apple.com/videos/streaming/examples/bipbop_16x9/bipbop_16x9_variant.m3u8
e.g.
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="bipbop_audio",LANGUAGE="eng",NAME="BipBop Audio 1",AUTOSELECT=YES,DEFAULT=YES
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="bipbop_audio",LANGUAGE="eng",NAME="BipBop Audio 2",AUTOSELECT=NO,DEFAULT=NO,URI="alternate_audio_aac/prog_index.m3u8"
You set up Airplay from e.g. iPhone or Mac or iPad to Apple TV or Mac.
Expected behavior:
You see in AVPlayer and QuickTime Language Audiotrack Dropdown containing info about LANGUAGE and NAME on Airplay Sender as on Airplay Receiver - the User Interface between playing back a local Stream or Airplay-Stream is consistent.
Current status:
You see in UI of Player of Airplay Receiver only Information of Language Tag.
Question:
=> Do you have an idea, if this is a missing feature of Airplay itself or a bug?
Background:
We'd like to offer additional Audiotrack with enhanced Audio-Characteristics for better understanding of spoken words - "Klare Sprache".
Technically, "Klare Sprache" works by using an AI-based algorithm that separates speech from other audio elements in the broadcast. This algorithm enhances the clarity of the dialogue by amplifying the speech and diminishing the volume of background sounds like music or environmental noise. The technology was introduced by ARD and ZDF in Germany and is available on select programs, primarily via HD broadcasts and digital platforms like HbbTV.
Users can enable this feature directly from their television's audio settings, where it may be labeled as "deu (qks)" or "Klare Sprache" depending on the device. The feature is available on a growing number of channels and is part of a broader effort to make television more accessible to viewers with hearing difficulties.
It can be correctly signaled in HLS via: e.g.
https://ccavmedia-amd.akamaized.net/test/bento4multicodec/airplay1.m3u8
# Audio
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="stereo-aac",LANGUAGE="de",NAME="Deutsch",DEFAULT=YES,AUTOSELECT=YES,CHANNELS="2",URI="ST.m3u8"
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="stereo-aac",LANGUAGE="de",NAME="Deutsch (Klare Sprache)",DEFAULT=NO,AUTOSELECT=YES,CHARACTERISTICS="public.accessibility.enhances-speech-intelligibility",CHANNELS="2",URI="KS.m3u8"
Still there's the problem, that with Airplay-Stream you don't get this extra information but only LANGUAGE tag.