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Aaron Torpy
March 29, 2005, 15:22:34
Hi Marc, Bernd and forum,

I was wondering if anyone had experience sending large-frame video (eg 768x576 or 640x480) using the IMVNetworkRenderer3 / IMVNetworkSource filters?

While I can send/receive small video OK (eg 320x240), I find that *all* MPEG keyframes in the large-format video are being dropped during transmission, even though the video stream bit-rate (1-2Mbit/s) is much lower than the available network bit-rate (1Gb/s optical LAN).

To make sure that the problem wasn’t due to someone else hogging my network bandwidth I threw some huge files over the LAN before and after my UDP tests, and did indeed achieve >500Mbit/s. Also, when I connected the computers directly in a peer-to-peer network, the problem went away.

I am guessing, therefore, that one of the LAN routers is dropping some of the IP packet fragments during keyframe transmission when the instantaneous UDP bit-rate exceeds the routers’ receive buffer size. Does this sound likely? If so, can anything be done to 'smooth-out' the UDP bursts from MVNetworkRenderer? Indeed, can anyone offer any remedies to this situation?

Cheers,
Aaron Torpy