Using the Camera Server

This information describes in a little more detail how you can use your camera server to take exciting snapshot pictures. It also discusses some of the more advanced design features and describes how to use the unit effectively to realize its full potential:

Snapshots
Using snapshots in your web pages
External web sites
Automatic Picture Updates
CRON script

Snapshots

A picture image generated by the camera server is referred to as a snapshot. The following information describes how to take a snapshot and also defines the various types of snapshots file that can be produced.

To produce a snapshot that is presented within the camera server Home Page, simply enter the chosen Internet address or Host name of your unit into the URL of your Web browser. A new snapshot is displayed within the camera server Home Page every time the URL reference is reloaded.

Snapshot files

For each snapshot taken, a JPEG file is created and stored within the internal memory of the unit.Snapshots can be created in different file sizes, e.g. fullsize, halfsize etc.

To generate clean snapshots that are not embedded within the camera server Home Page, your preferred file size for the target JPEG file must be specified within the URL of your Web browser.

The following picture sizes and respective file references are available for snapshots:

fullsize.jpg - Full size JPEG snapshot comprising 352 x 288 pixels with a typical file size of 30 kbytes.
halfsize.jpg - Half size JPEG snapshot comprising 176 x 144 pixels with a typical file size of 15 kbytes.
lastshot.jpg - This file is automatically generated in addition to one or other of the above file types and contains the picture data for your previously triggered snapshot. Subsequently, this may be either a fullsize of halfsize picture file.
hugesize.jpg - This is the highest resolution snapshot available comprising 704 x 576 pixels. As opposed to the ‘fullsize’ and ‘halfsize’ images, this type of snapshot is software generated which takes about 18 seconds.
zoom.jpg - Derived from the from the center of ‘hugesize’ and comprises 352 x 288 pixels. Generation time = approx. 8 secs.

To integrate live snapshot images into your own web pages and applications, simply refer to the URL of the camera server as detailed below:

Examples

http://cameraname/fullsize.jpg

http://cameraname/halfsize.jpg

Note:
To obtain a separate snapshot image that is not embedded within the camera server Home Page, you must define your sizing preference as described above.

Using Snapshots in your Web Pages

Follow this procedure to integrate exciting live snapshots into your own web pages:

Create your Home Page using your preferred HTML creation tool, i.e an ordinary text editor, or a dedicated HTML design application, such as Microsoft Internet Assistant, Front Page, Adobe PageMill, etc.
Enter a URL in your browser as described below:

http://cameraname/fullsize.jpg

This URL reference must define the Internet address (or host name) of your camera server and the type of snapshot file that you wish to create, e.g. fullsize, halfsize, hugesize, lastshot or zoom.

To include the snapshot into your web page, simply provide a HTML reference to the snapshot within the target web page, as detailed below:

<HTML>

                <HEAD>

                <TITLE>Sample page</TITLE>

                </HEAD>

                <BODY>

                <H1>Welcome to Axis Web camera
                demo</H1>

                <IMG ALT="Full-size JPEG Image"

                SRC="http://cameraname/fullsize.jpg"

                WIDTH="352" HEIGHT="288">

                <P>This picture is taken right
                now!</P>

                <P>Follow <a href =
                "http://www.axis.com">this
                link</a> to get to our corporate Home Page!

                </BODY>

                </HTML>

External Web Sites

When using the camera server over the Internet, we recommend that it is accessed over an assisting web server and not directly. This is because the camera server has limited capacity for handling the extra amount of buffering required.

Note:You can use the CRON script facility to collect snapshots periodically.

If your web site does not have heavy traffic, it is possible to use the URL directly to thecamera server. However, this has three main drawbacks:

Your camera server may be located on the other side of the firewall.
The camera server cannot handle more than 5 simultaneous requests.
Generating large files, such as hugesize.jpg, is very time consuming. However, when used with a CRON script, the delay will not be noticed.

Automatic Picture Updates

The camera server supports three methods for automatic picture updates, namely:

Server push
Java image feed
Refresh image feed

These are available from links on the camera server Home Page.

Note: To terminate the automatic picture updating, you can click Stop or enter another URL in the Web browser.

Server push - The Server push function effectively pushes new snapshots into your Web browser continuously.

Frequency - The frame rate depends on how fast the camera server can deliver the snapshot data over the available network bandwidth. Therefore, you cannot adjust the frequency of the Server push snapshots within your Web browser.

Number of clients - In order to limit the memory overhead that this facility demands, a maximum number of 5 clients can simultaneously activate a Server push link to the same camera. Once this client threshold has been exceeded, a single snapshot image is produced for all additional clients that are trying to activate the link.

Note: Server push is currently only supported by Netscape Navigator. However, you can download an ActiveX component from the Axis web site that will provide the same functionality within Internet Explorer.

Java Image Feed - This function is implemented within a Java applet that can be started from anywhere on the network. The refresh rate is programmable.

Refresh Image Feed - This function instructs your Web browser to collect a new snapshot at an adjustable rate. It is supported by most standard Web browsers.

Tech-Support@axis.com