smst;141995 Wrote: > For example, this S/PDIF information mentions MPEG audio as one possible > thing to put into the stream (although it might be speculative): > > http://www.epanorama.net/documents/audio/spdif.html > > And indeed it seems that Harmon Kardon produce an amp capable of > receiving MP3s over S/PDIF: > > http://forum.doom9.org/showthread.php?t=23822 > > Of course, the existing players will only be able to produce stereo > from the new MP3 Surround files, but if we could wrap up an MP3 in the > same way we can wrap an AC3 or DTS file, we might still be able to > transmit it to a suitable receiver. (I wonder if anybody other than HK > make such a thing?) And if we can transmit a stereo MP3 to a receiver, > I'd imagine that adding support for MP3 Surround would be fairly easy, > should a receiver come to exist which can support it. > > Transformed MP3s would almost certainly be as big as their decompressed > stereo-WAV equivalents, but would compress well to FLAC due to all the > padding (going by the way AC3/DTS behaves). Unfortunately my receiver > can't take MP3 files, but it would certainly be interesting to get this > going. And if it could be made to work, the SB2/3 firmware could > probably do it for us.
Interesting! Well that would be the way. You'd need a firmware change so that the SB could pass surround MP3 without decoding it over S/PDIF, then a receiver capable of decoding surround MP3. This might be able to avoid the licensing cost on SD's part. I would assume a receiver capable of decoding surround MP3s is capable of decoding 2-channel MP3s, so all the SB would have to do is transmit the MP3 bits over S/PDIF. It certainly can recognize MP3 from other streams, all it has to do is pass the raw data over rather than convert it to PCM like it currently does. Not knowing how the SB firmware works, I'm not sure if this could be done. But it will be rebuilding the MP3 file from the SlimProto packets, just like it's doing now. However it will bypass the decoder and transmit the reassembled MP3 data directly over S/PDIF. Since this is handled by SlimDSP software, it should be possible to change it as it's not "hardwired" if you will. It'll certainly be easier to do it this way rather than heroics at the server decoding the surround MP3, then re-encoding it into DD or DTS, then getting that into SlimServer - and incurring two or maybe even three licensing costs in the process! (Surround MP3, DD Live and/or DTS Conncect). At first I thought "surround MP3, why do I want a lossy format?" But that's exactly what DD and DTS are, lossy multichannel. Lossless multichannel is DSD, MLP and (new) Dolby TrueHD. Those can't be handled by S/PDIF, no way no how, plus they are content-protected. -- Mark Lanctot ------------------------------------------------------------------------ Mark Lanctot's Profile: http://forums.slimdevices.com/member.php?userid=2071 View this thread: http://forums.slimdevices.com/showthread.php?t=28112 _______________________________________________ discuss mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/discuss
