Solved

Webcam Photo not refreshing

Posted on 2011-03-09
8
599 Views
Last Modified: 2012-05-11
We are trying to put a webcam on our website. My page www.downtownrapidcity.com/camera.html is set to refresh every 5 seconds which it does. But the photo doesn't change from the webcam. I have to manually click on Refresh on my browser window to get the image to change.

If you go to http://208.117.100.102/cgi-bin/viewer/video.jpg where it is pulling the photo, it updates with each refresh of the page.

How do I get the image to change with each auto refresh?
0
Comment
Question by:katlees
  • 5
  • 2
8 Comments
 
LVL 2

Assisted Solution

by:Roza
Roza earned 200 total points
ID: 35086352
I guess browser is cacheing your image instead of reloading it when page reloads.

Try adding

<META HTTP-EQUIV="Pragma" CONTENT="no-cache">
<META HTTP-EQUIV="Expires" CONTENT="-1">

between HEAD tag.
0
 
LVL 16

Accepted Solution

by:
sjklein42 earned 300 total points
ID: 35086725
My approach is to add a random tag to the image URL each time it is fetched to bypass caching.  Sometimes it is the webcam software itself that does the caching.

<SCRIPT LANGUAGE="JavaScript">

url='http://208.117.100.102/cgi-bin/viewer/video.jpg?v=';

var image1 = new Image();
function RefreshMyCamera()
{
    if ( ( image1.src != '' ) && (image1.complete) )
    {
        document.images['mycamera'].src = image1.src
    }
    imgno = Math.round(Math.random()*215815);
    image1.src = url + imgno;
    setTimeout('RefreshMyCamera()', 5000);  // inter-frame delay in msec
}
</script>

<img border='0' src='http://208.117.100.102/cgi-bin/viewer/video.jpg' name='mycamera'>

<SCRIPT LANGUAGE="JavaScript">
setTimeout('RefreshMyCamera()', 10);
</SCRIPT>

Open in new window

0
 
LVL 16

Expert Comment

by:sjklein42
ID: 35086822
You video server (camera) appears to be down.

Instead of an image it is returning this:

http://208.117.100.102/cgi-bin/viewer/video.jpg

HTTP/1.1 500 Internal Server Error
0
Optimizing Cloud Backup for Low Bandwidth

With cloud storage prices going down a growing number of SMBs start to use it for backup storage. Unfortunately, business data volume rarely fits the average Internet speed. This article provides an overview of main Internet speed challenges and reveals backup best practices.

 
LVL 16

Expert Comment

by:sjklein42
ID: 35087287
The javascript approach has the added advantage that only the image is updated, so you can embed it in a static web page and not have to refresh the whole page.

Did we take down your camera server?
0
 

Author Comment

by:katlees
ID: 35087298
I don't know. Another company does the camera server I have put in a trouble ticket to them. Thanks... as soon as it is back up I can try these fixes.
0
 
LVL 16

Expert Comment

by:sjklein42
ID: 35087977
Improved version.  I have it pointing at my webcam for now.  You can change the URL (in two places) and try it with your camera when your server comes back online.

<SCRIPT LANGUAGE="JavaScript">

var url='http://sjklein.dyndns.org:11001/cam_1.jpg?';
var frq=1500;           // interval in msec

function PrefetchImage()
{
    var imgno = Math.round(Math.random()*215815);
    image1 = new Image();
    image1.src = url + imgno;
}

var imgno;
var image1;

PrefetchImage();

function RefreshMyCamera()
{
    if (image1.complete)
    {
        document.images['mycamera'].src = image1.src
        PrefetchImage();
    }

    setTimeout('RefreshMyCamera()',frq);
}
</script>

<img border='0' src='http://sjklein.dyndns.org:11001/cam_1.jpg' name='mycamera' width=95%>

<SCRIPT LANGUAGE="JavaScript">
setTimeout('RefreshMyCamera()', 10);
</SCRIPT>

Open in new window

0
 
LVL 16

Expert Comment

by:sjklein42
ID: 35090889
I'm afraid my code is taking down the camera server.
0
 

Author Closing Comment

by:katlees
ID: 35101354
Both responses worked but I liked the one where I could embed it right into the website! Thanks guys
0

Featured Post

Comprehensive Backup Solutions for Microsoft

Acronis protects the complete Microsoft technology stack: Windows Server, Windows PC, laptop and Surface data; Microsoft business applications; Microsoft Hyper-V; Azure VMs; Microsoft Windows Server 2016; Microsoft Exchange 2016 and SQL Server 2016.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
topping3 challenge 14 80
Problem to start Neon 20 106
Is doing tutor.com teaching in my situation advisable? 2 88
Removing line numbers from left column in config file 7 52
Although it can be difficult to imagine, someday your child will have a career of his or her own. He or she will likely start a family, buy a home and start having their own children. So, while being a kid is still extremely important, it’s also …
Computer science students often experience many of the same frustrations when going through their engineering courses. This article presents seven tips I found useful when completing a bachelors and masters degree in computing which I believe may he…
This tutorial will introduce the viewer to VisualVM for the Java platform application. This video explains an example program and covers the Overview, Monitor, and Heap Dump tabs.
The goal of the tutorial is to teach the user how to use functions in C++. The video will cover how to define functions, how to call functions and how to create functions prototypes. Microsoft Visual C++ 2010 Express will be used as a text editor an…

777 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question