Products can be read from a file format which cannot be written to or within an archive which makes it inconvenient to add new files.
Quicklooks should be created lazily on demand.
There could be more than one quicklook per product.
Quicklooks may be of different dimensions.
If a product comes with a quicklook, browse or preview image, the reader shall generate a quicklook from this.
Products should specify a quicklook band name.
Products with a file and reader will call first the reader to generate a quicklook on demand. If there are no file and reader or the reader does not have a quicklook, then the quicklook shall be generate based on the given quick look band name of the product.