CoverService

Provides an easy access to a bitmap version of the publication cover.

While at first glance, getting the cover could be seen as a helper, the implementation actually depends on the publication format:

Some might allow vector images or even HTML pages, in which case they need to be converted to bitmaps.
Others require to render the cover from a specific file format, e.g. PDF.

Furthermore, a reading app might want to use a custom strategy to choose the cover image, for example by:

iterating through the images collection for a publication parsed from an OPDS 2 feed
generating a bitmap from scratch using the publication's title
using a cover selected by the user.

Functions

open override fun close()

Closes any opened file handles, removes temporary files, etc.

abstract suspend fun cover(): Bitmap?

Returns the publication cover as a Bitmap at its maximum size.

open suspend fun coverFitting(maxSize: Size): Bitmap?

Returns the publication cover as a Bitmap, scaled down to fit the given maxSize.