In SharePoint 2013, there is a new feature called Image Renditions. I think if the content owners use this feature wisely, it will definitely reduce the load on the bandwidth.
What does the feature do? Image renditions lets the site owners define what sizes the images can be scaled to when adding an image to a page. It basically allows the author
Here is how you set it up.
1. Enable Blob Cache for the web application. Enable it through web.config.
Open the web.config, search for “<BlobCache” and set the enabled property to “true”
2. Go to the site collection settings->Image Renditions.
If you have not enabled the blob cache from step 1, you will get the following error
3. Add image renditions that you need.
At this point the setup is complete and the users can start using it. The following screen shots show how to use the image renditions.
1. Edit a page.
2. Add an image to the page.
3. In this example, I used a large ~800 Kb image.
4. In the Design tab of the Ribbon, you will see a drop down for Pick Rendition.
5. Select a rendition. For this example, let’s select the Profile Picture rendition.
In the profile picture rendition, we have just specified the width and not height. Hence the image will match the width and scale the height keeping the aspect ratio.
If we select the Thumbnail rendition, the height and width are fixed. It loses the aspect ratio.
Now how does this help reduce bandwidth? When you select a rendition, SharePoint will create the image of that size and add to the blob cache. So instead of transferring 800 Kb, it will only transfer the smaller image to the client machines.
As you can see in the above image, the same image is of the size 28kb. I will dive deeper in the later posts to explain how SharePoint 2013 actually achieves this.
(I need to verify if there are any changes in the Beta, since the last refresh).
