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Re: Question on pipelined multiple image acquisition

From: Daniel Stenberg <daniel_at_haxx.se>
Date: Wed, 24 Jan 2007 12:08:37 +0100 (CET)

On Tue, 23 Jan 2007, Zheng wrote:

> Briefly speaking, the task is to use a computer to acquire images from one
> remotely connected webcam which monitors a space with moving objects. The
> current setup can only handle a new acquistion request after the previously
> acquired image (100KByte) is received by the computer. Therefore the image
> updating frequency is limited by the time delay (about 200ms) spent during
> their acquisition and transmission. My question is whether or not this
> process can be improved with multiple thread or pipelining support, i.e. to
> acquire new image before the previouly one is received and have more than 1
> image processed simultaneouly.

Since it can only handle a new "acquistion request" when the previous transfer
is completed, then how would it deal with pipeling when it certainly WILL get
a new request before the previous transfer is completed?

> I find that the project of High Performance libcurl might be the promising
> way to go for it. But I don't know if the time period between two sequential
> acquisition commands can be determined according to the designer's will.

When the app adds an easy handle that can be pipelined it will be sent out as
soon as possible, so while this is controllable somewhat by the application I
figure any kind of detailed timing will not be possible.

(To me it sounds like you have the wrong kind of camera HW to get this amount
of pictures from, but I guess that is off-topic here.)

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Received on 2007-01-24