[vdr] Re: mpeg1 layer 2 (mp2) -> iec958 ?

[Sven Goethel <sgoethel@jausoft.com>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Monday 13 October 2003 23:30, Sven Goethel wrote:
> are the most digital receivers able to
> receive mp2 via iec958 ?
>
> is this a stdandard ?
>
> if so .. may we can pass this digital data with bitstreamout
> as well ?
>
> werner ?
>

well in werner's linked page:
	http://www.epanorama.net/documents/audio/spdif.html
they say:


+++

Characteristics

Standard IEC958 "Digital audio interface" from EBU (European Broadcasting Union) details:

    * Audio format : linear 16 bit default, up to 24 bit expandable
    * Allowed sampling frequencies (Fs) of the audio:
          o 44.1kHz from CD
          o 48 kHz from DAT
          o 32 kHz from DSR 

+++

Multi channel audio and S/PDIF

IEC958 was named IEC60958 at 1998. IEC60958 (The S/PDIF) can carry normal audio and IEC61937 datastreams. 
IEC61937 datastreams can contain multichannel sound 
like MPEG2, AC3 or DTS. When IEC61937 datastrams are transferred, 
the bits which normally carry audio samples are replaced with the databits from the datastream 
and the headers of the S/PDIF signal. 
Channel-status information contains one bit (but 1) which tells if the data in S/PDIF frame is 
digital audio or some other data (DTS, AC3, MPEG audio etc.). 
This bit will tell normal digital audio equipments that they don't try to play back this data 
as they were audio samples. (would sound really horrible if this happens for some reason).

The equipments which can handle both normal audio and IEC61937 
just look at those header bits to determine what to do with the received data.

+++

so we might can add at least to more formats to bitstreamout:

- - encoded samples of 48 kHz, e.g. of mp2
- - mp2 itself encapsulated like todays ac3/dts ..

is this true ?

if so .. there would be no more need to 
switch to analog audio for mp2 ...

cheers, sven
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.3 (GNU/Linux)

iD8DBQE/ixvOHdOA30NoFAARAmOEAKCvmVc/5D3uaDFbyK7hh4eonpuk8ACffiyN
PEhW4+SwawMdVUNXzBym8Uk=
=FqQ2
-----END PGP SIGNATURE-----



-- 
Info:
To unsubscribe send a mail to ecartis@linuxtv.org with "unsubscribe vdr" as subject.