Kraken is a service that compresses the size of the images while preserving the quality of each image, basically its function is to reduce the size of the images before being saved in the image library after making the connection setting for Kraken the user would be in charge of uploading the images and this service would be in charge of making the size reduction to improve the loading of images on the site.

To configure the Kraken image optimization, follow the next steps:

1. Open the Sitefinity Backend and Login using an Administrator Account.

2. Navigate to Sitefinity Settings -> Advanced section

3. Navigate to Libraries -> FileProcessors -> Kraken IO Image Optimization as the picture show.

4. The connection values is added in this section:

Supported Extensions: are the extensions supported by Kraken to optimize images (This field is already filled by default).

ApiKey: value generated by Kraken.

ApiSecret: value generated by Kraken.

LossyCompression: this value applies an optimization preserving the visual identity and qualities of the image by choosing the best value between quality and size for each image. This field takes a true or false value.

MinSizeToRender: (Optional value) specify the number of bytes from which to start optimizing images with Kraken. If this values is empty and you have already added the credentials to make the connection to Kraken it will apply the optimization to all images no matter what size they are.

5. After this parameters are configured when you upload a new images it will be rendered by Kraken.

6. If you want to optimize the existing images you have to add other configurations in addition to defining the connection to Kraken.  To configure this service follow the steps below:

a. Navigate to Settings -> Advanced navigate to ImageOptimization as picture show.

b. By default this task will be disabled, to enable it check the  “Enable Image optimization scheduled task” checkbox setting.

c. “Image optimization cron specification” is a setting where we specify the time the task will be executed.

d. “Batch size” is the size of images to be processed by default its value is 100 but it can be changed.

e. “Enable image optimization detail logging” by checking this box will log detail of all processed image information.