Re: Lot of jitters occur during Video streaming through HostAP


From: Jouni Malinen (jkmaline_at_cc.hut.fi)
Date: 2002-08-12 16:33:18 UTC



On Mon, Aug 12, 2002 at 08:12:29PM +0530, Manjunathan PY wrote:

> Can anyone tell me why there is a lot of jitters during video streaming
> through D-Link DWL 650 PCMCIA card which acting as a Access Point.
>
> In fact the video is displayed frame by frame on the mobile station.

Is the video displayed on the AP running Host AP driver or in the station associated to the AP (running Host AP driver)? Which version of Host AP driver you used?

Prism2 cards use quite CPU consuming method for frame copying between the card and host CPU. Current version of the driver does this copying in the interrupt handler for RX and with interrupts disabled for TX (this should be changed to operate without disabling interrupts if possible). This might well cause problems to applications needed exact timing and small latencies like video playback.

-- 
Jouni Malinen                                            PGP id EFC895FA


This archive was generated by hypermail 2.1.4.