Nick_G wrote: 
> Thanks bpa. I've also updated to PlayHLS V2, and the SBT now connects to
> HLS streams more quickly than before and also now shows file type and
> bitrate info (before it just said 'Apple HLS'). This makes me wonder, is
> transcoding still going on, or is it now decoding the streams natively?

Assuming the "it" to be the SB Touch in the phrase "is *it* now decoding
the streams natively?" 

"Apple HLS" is just a piece of text to indicate that the stream had a
MIME type that meant it was going to be processed by the PlayHLSv1
plugin.  There is no other significance.

HLS streams can be typically have the following audio formats: MP3,
ADTS/AAC, MPEG2/AAC or MPEG4/AAC. 

PlayHLSv1 - uses ffmeg to take the HLS stream and produce a MP3, PCM or
Flac format - depending on the player capability. ffmpeg would transcode
bit rate and format into whatever player could handle (or 44.1kHz/16bit
for PCM).  The source bitrate , sample size etc or metadata in the
stream is not available to LMS from ffmpeg.

The plugin prcoesses the HLS stream "packets" (e.g. MPEG2, MPEG4) within
LMS so it has access to bit rates, sample size and metadata (e.g. track,
artist, station, images) if available and in a known format (metadata
data format is not standardized and can vary by station/CDN). This data
can then be presented via LMS to the UI.  

If the source is AAC wrapped in ADTS/AAC, MPEG2/AAC or MPEG/AAC, the
plugin produces an ADTS/AAC byte stream which is the AAC format that can
be decoded "natively" by Touch, Radio and most SB software players - so
these players can play the stream without LMS transcoding but still need
the plugin (i.e. not direct streaming).

Older player such as SB3, Classic, Boom Transporter, Receiver,
Softsqueeze and some builds of Squeezeplay cannot play AAC nativley - in
which case LMS will transcode to a compatible format according to the
FileTypes settings for AAC.

If the source format is MP3, then all players can play it natively.

The main "performance" difference between PlayHLSv1 and PlayHLS v2  
- in v2 no ffmpeg so no additional process and memory (ffmpeg is big)
- in v2 LMS AAC is only transcoded as required and then using standard
LMS faad which is lighter than ffnpeg.
- v2 plugin is platform agnostic - no need to find & install a suitable
ffmpeg/avconv 
- in v1, Because ffmpeg couldn't generate suitable ADTS/AAC streams, AAC
was transcoded even for AAC capable players.


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