[PD] Audio streaming for 3 or more channels?

[Martin Peach]

On 2014-07-21 12:50, Bektur wrote:
>
>> I’m running a simple iOS application with libpd and udpreceive~ objects in the patch. The audio is sent from a computer with udpsend~ object, with only one channel currently being used. Whenever I stream to a single IP address everything works fine with almost unnoticeable latency. However, when I try to broadcast to multiple addresses in the network (as shown in udpsend~ help patch), I get two kinds of errors:
>>
>> – On OS X, block size >= 512 triggers “Message too long (40)” error. It happens only on OS X (tried the same patch on ubuntu, and this error didn’t reappear), one of the possible solutions I found was to use smaller block size, but in such case it would cause the second kind of error
>>
>> – On a client I get "udpreceive~: bad header tag (1)” error with incrementing numbers in the error. At first, I thought the libpd implementation was to blame, but it also happened when I run the same send and receive patches on two different computers running Pd-extended and connected over a local wireless network.
>
>
> I haven’t found any workaround for this yet, but I’m planning to try reproducing these issues on a windows machine with ASIO drivers.

I suppose if you do it over a wired connection it will work better. 
Probably the WiFi is dropping packets and retransmitting, so things get 
out of sync. I don't know how broadcast UDP is implemented in WiFi, but 
I imagine it involves sending copies of the same packet to each receiver 
rather than a single packet addressed to multiple receivers.

Martin