Track Ordering Issue with DiscSubtitle

[simoncn]

The DIDL-Lite in post #8 shows why this isn't working with control points that "scrape" metadata instead of showing the Browsing tree created by MinimServer.

For a multdisc album, MinimServer returns the following for the album contents:

-- container for album
---- container for first disc title (with no contents)
---- track 1 for first disc
---- track 2 for first disc
---- other tracks ....
---- container for second disc title (with no contents)
---- track 1 for second disc
---- track 2 for second disc
---- other tracks ....
---- etc.
-- end container for album

The <container> entries don't have any contents. They are just dividers indicating the end of one disc and the start of the next disc. This means that each track is a child of the album, not a child of the disc.

To make this work with control points like Serento that create their own browsing structure based strictly on metadata, MinimServer would need to return something like this:

-- container for album
---- container for first disc
---- track 1 for first disc
---- track 2 for first disc
---- other tracks ....
-- end container for first disc
---- container for second disc
---- track 1 for second disc
---- track 2 for second disc
---- other tracks ....
-- end container for second disc
-- etc.
-- end container for album

In "standard" UPnP control points, this would show the album as just a list of discs with no tracks displayed. To see tracks for a disc, the user would need to select the disc at the top level. This is how groups of tracks created using the GROUP tag are shown by MinimServer.

It would be worth trying the following aliasTags setting to see if this enables Serento and other affected control points to work correctly:

DiscSubtitle:Group

This replaces DiscSubtitle tags with Group tags in the MinimServer library without changing the files on disc. An aternative is to add this to the tagValue setting:

Group.replace={DiscSubtitle}

This copies DiscSubtitle tag values to Group tag values and retains the DiscSubtitle tag values.