I am using PHP with Tika to extract information about various Joomla!
attachments before sending them to Solr.
I use the JSON flag to extract a file's metadata which in most cases
results in valid JSON.
However, I've noticed with MP3s that the track number is not always quoted:
"xmpDM:trackNumber":00
but in other instances it is:
"xmpDM:trackNumber":"5/10"
The first instance will lead to PHP's json decode method reporting an
invalid syntax error, the second instance will decode successfully.
Cheers
Hayden