This blog post lists the query string parameters used in URLs of media items in the Sitecore ASP.NET CMS.
The Presentation Component Reference manual on the Sitecore Developer Network (SDN) lists parameters that you can pass to the <sc:image> XSL control, which renders the HTML markup to display the image referenced in a field of type Image. Sitecore adds corresponding parameters to the query string of the URL for the media item.
Some of these query string parameters affect image aspects, such as sizing. Others apply to any type of media, such as language, version, database, and cache functionality.
Here is a list of the supported query string parameters:
In general, avoid constructing URLs using these query string parameters explicitly. For example, use the Sitecore.Data.Items.Item.Appearance.Icon property to retrieve the icon, the Sitecore.Resources.Media.MediaManager.GetThumbnailUrl() method to retrieve the URL, or the Sitecore.Resources.Media.MediaManager.GetMediaUrl() method with the Sitecore.Resources.Media.MediaUrlOptions class to construct the URL programatically. Remember to use something like the Sitecore.StringUtil.EnsurePrefix() method to ensure that media URLs begin with a slash (/) rather than a tilde (~). Media URLs that begin with this character can result in multiple URLs for media items and sooner exceed IIS path length limits. You can download some sample code that shows these techniques.
Very useful information. I found few more. What does it mean if my url contains querystring as &mo=preview&we=1. What is the purpose of sc_wede=1 in cookie
I'd take a guess that we or wede is web edit and mo is mode.
Check out the Shared Source Module 'Image Cropper' by Igloo Digital. It allows a crop=1 parameter to trim the image so you don't get the letter boxing background. blog.igloo.com.au/
There is another parameter which can be used to convert the image in grayscale : gray=1
// bc: Background color (defaults to black) Can't we change this default colour to "White"?
My thought would be to try overriding the ResizeProcessor processor in the getMediaStream pipeline to set this to white if it is black (or maybe null). If you can check for null, that would be better because you might in some cases want black. If you cannot check for null and may need black, maybe disable your logic if bc appears in the query string.
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