On Thu, 04 Aug 2005 03:00:51 +0100, Pooh Bear wrote:


Rich Grise wrote:

On Thu, 04 Aug 2005 01:07:23 +0100, Pooh Bear wrote:

That's the raw data rate only !

Now you have to add overhead for the frequency hopping stuff, handshaking, whatever
and redundancy for lost packets - and I've no idea how the data's encapsulated -
there'll doubtless be extra stuff there too. I'm not calculating this myself, I have
it on good authority from some guys who are developing the product. I was quite
surprised how much overhead is required myself actually.

You don't have to use TCP/IP, and you don't need, or even want, lost
packet redundancy, at least not for streaming audio. If you need a
protocol at all, use something like UUCP.

If you don't account for lost packets what's going to happen to any lost audio data ? I'll
ask some more next time I talk to the guys about the protocol they're using.


You leave it gone, because if you try to resend it, you'll lose ensuing
packets, or at least they'll get out of order. You drop it, and keep
on truckin'...

And if it's just streaming bits, you won't lose whole packets, and a
bit or two here and there is insignificant for, say, MP3. ;-)

Cheers!
Rich

Rich Grise wrote:

On Thu, 04 Aug 2005 03:00:51 +0100, Pooh Bear wrote:


Rich Grise wrote:

On Thu, 04 Aug 2005 01:07:23 +0100, Pooh Bear wrote:

That's the raw data rate only !

Now you have to add overhead for the frequency hopping stuff, handshaking, whatever
and redundancy for lost packets - and I've no idea how the data's encapsulated -
there'll doubtless be extra stuff there too. I'm not calculating this myself, I have
it on good authority from some guys who are developing the product. I was quite
surprised how much overhead is required myself actually.

You don't have to use TCP/IP, and you don't need, or even want, lost
packet redundancy, at least not for streaming audio. If you need a
protocol at all, use something like UUCP.

If you don't account for lost packets what's going to happen to any lost audio data ? I'll
ask some more next time I talk to the guys about the protocol they're using.


You leave it gone, because if you try to resend it, you'll lose ensuing
packets, or at least they'll get out of order. You drop it, and keep
on truckin'...

And if it's just streaming bits, you won't lose whole packets, and a
bit or two here and there is insignificant for, say, MP3. ;-)

My best guess is that the simplest way to deal with occasional lost packets is simply to send
the data twice and discard the erroneous data. Doing stuff in real time is rather different to
computer networking where it doesn't matter too much if the file's delayed a bit.

I hear you about mp3 :-p

My interest is actual proper 16 bit linear pcm. You'll definitely notice a lost packet with that
! I don't think that clicks will be very acceptable. ;-)

Graham