Tag Cache (Tagdatabase) fileformat

[akleinwaechter]

Hi,

in which format is the tagcache stored in Rockbox? Can I access the content of the cache with an external programm on a pc?

I would like to write a small programm that imports the the additional information (how often played, last played...) to musikcube (and if possible vice versa). I did this stuff from iTunes to musikcube already. If I can manage this last step. I leave iTunes behind me  

Best regards
Alex

[bascule]

To start off, the data is stored (as plain text) in the *.tcd files in /.rockbox

I know someone has written a program to interrogate the files, but I can't access the Wiki at the moment to check.

EDIT: My mistake, it was to generate database files from the iTunes db:
http://www.rockbox.org/twiki/bin/view/Main/ConvertiTunesDBtoTagCache

last.fm (audioscrobbler) logging support, however, is built in to rockbox. Maybe you could turn that setting on and use that data instead. This looks more promising...

http://www.rockbox.org/twiki/bin/view/Main/LastFMLog

[roolku]

in which format is the tagcache stored in Rockbox?

AFAIU The database_*.tcd files contain a sorted list of all unique values for a particular (text-) tag - including the filepath in database_4.tcd - and a pointers back to the main index file. The main index database_idx.tcd contains the tag entries for every file, where numerical tags are stored directly and text tags are represented as an offset in the database_*.tcd file.

Can I access the content of the cache with an external programm on a pc?

Possible, but not straight forward. For example you have to take into account the endianness of your platform.

I would like to write a small programm that imports the the additional information (how often played, last played...) to musikcube (and if possible vice versa).

Have you considered using the export and import function ? The generated text file should be a lot easier to parse or generate.

[akleinwaechter]

Thank you all for your replies. I will take a closer look to the import and export functions. If the additional information is included it will be the solution.  I will post my programm when finished.

Alex

[bzavala]

I was just looking at muskcube a couple of days ago and also thought how could it'd be if from rockbox, there was a way to update how often a file has been played...

So I take it, the Tag Cache does not store count or last played... is this correct?

Also..  is there a program to generate the tag cache file from a PC?  my music folder on my ipod is synched to my music folder on my PC....  I ask because when you try to create or update the tag cache using the device, it takes some time...

Thanks!

Ben

[bascule]

So I take it, the Tag Cache does not store count or last played... is this correct?

No, the database has a simple but effective runtime database, storing playcount, an autoscore based on average amount of the track that has been listened to and a sequential count:

http://www.rockbox.org/twiki/bin/view/Main/DataBase#Gather_Runtime_Data_Experimental

Also..  is there a program to generate the tag cache file from a PC?  my music folder on my ipod is synched to my music folder on my PC.... 

Not as far as I know, unless you use iTunes, when the application linked in my first post will do the trick.

[akleinwaechter]

Perhaps I build a tool similar to the itunes to tag cache conversion tool for musikcube which has the additional ability of importing the playcount data out of the tag cache database to musikcube. Musikcube is sql database driven, so it should be no big problem when I can extract the information from rockbox. If done I have similar capabilties like the couple of itunes and ipod.

regards
Alex

[akleinwaechter]

First part of the work is done. My tool is now able to import all itunes information to musikcube. The next step is the rockbox to musikcube synchronisation. I hope it will be done within march 2007.

My tool can be downloaded under:
http://www.activecontext.de/itutomc.aspx

Best regards
Alex