When an image is streamed from a script the script must be embedded inside an <img> and this causes problems when trying to pass variables through the application. A useful method is to use the URL to the embedded script to pass query string parameters.
The example on the previous page shows a script that draws a red square. With some modifications this colour could could be passed in the URL. Here is the new <img> tag:
The script generating the image would use the parameter as follows:
<cfobject action="create" name="Image" class="csImageFile.Manage">
<cfset Image.NewImage(200, 200, #URL.Colour#)>
Remember to encode the parameters using escape codes if they if they contain characters that will not pass through the URL.
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