Problem with WebCam and Cache

HCL Domino Domino Forum
1

Hi all,

I’ve just setup my new webcam, and wanted to create a little website where there’s an image that got updated every 2 seconds.

I downloaded a little program (pjWebCam) to capture an image and save it every 2 seconds to a locally mapped drive (W:). This mapped drive is actually a folder in my file-structure on my webserver (6.0.1) and I’ve created a little page that use a Java applet to refresh the picture every 2 seconds…

Heres the problem:

The picture dosn’t change. I know that the webpage resfreshes, and I know that the JPEG file gets overwritten with a new one every 2 seconds (using a pictureviewer I can see that it changes).

I believe that the problem is in the Image and File cache on the Domino server. I’ve tried to change the ‘Maximum cache size’ from the default 50 Mb to 0 Mb. This didn’t help… The picture still dosn’t update. Not even when I make a forced browser refresh (CTRL+F5 in IE).

Does anyone have any advice?

Kind regards,

Hans

Denmark

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Subject: Problem with WebCam and Cache

You can enforce browser refresh with a web header rule

Add these headers via a header document under your website document

Expires 0

Cache-Control No-Cache

for the URL of your picture

3

Subject: RE: Problem with WebCam and Cache

Hi Michael

I’ve tried what you suggested, but it still dosn’t seem to work. If I close my browser, and start it again, it loads the newest picture, but when the applet refreshes the image, its the same that’s loaded (eventhough it been replaces with a newer).

Any other ideas that I might try out?

4

Subject: Problem with WebCam and Cache

Hello Hans,

I am also trying to create a webcam. We hade the same problems. There are 4 meta tags you must enter.

this din’t do the complete job for IE. there for we used the folowing code to trick IE.

image.src = “http://…Image17_0_1.jpg?” + new Date().getTime(); (javascript).

This worked here.

But we have a problem chekking if the image (on disk) is available. How did you solve that?