Vuforia dataset size

Hello,

We are trying to create an app with a database of 100 image targets. The image targets would be printed on paper for augmenting with videos and the size of each image target is to be 8 cms width by 6 cms height. We uploaded 100 images to the Vuforia target manager to create the database. Each image target has a size of around 64 kb and the total size of the 100 images is around 6 + MB. The resultant database that Vuforia created is around 21.1 MB. 

Please advise us on how to reduce the size of the database. We indicated a width of 10 in the width field in the target manager.  Should we reduce this width since we don't expect our users to view the image target from more than a meter in distance? Will reducing the size of the images bring down the database size? 

We are looking to build an app based on the Vuforia video playback sample.

Please advise us on how to reduce the size of the image target database.

Thanks