Guys, this is Old French, not Old Occitan (Provençal as it's called in the English speaking countries).
The original lyrics can be found below this YouTube rendition by the Ensemble Perceval. You can find them here too with a translation into modern French and a longer version in Old French with a translation into modern French there. "Google translation" gives a rather accurate English translation of the modern French translation in spite of some mistakes.

Ja nuls om pres non dira sa razon
Adrechament si com om dolens non
Mas per conort deu om faire canson
Pro n’ai d’amis mas paure son li don
Anta lur es si per ma rezenson
So çai dos ivers pres

Or sapchon ben miei om et miei baron
Angles norman peitavin et gascon
Qu’ieu non ai ja si paure companhon
Qu’ieu laissasse per aver en preison
Non o dic mia per nula retraison
Mas anquar soi ie pres

Car sai eu ben per ver certanament
Qu’om mort ni pres n’a amic ni parent
E si’m laissan per aur ni per argent
Mal m’es per mi mas pieg m’es per ma gent
Qu’apres ma mort n’auran reprochament
Si çai me laisson pres

No’m meravihl s’ieu ai lo cor dolent
Que mos senher met ma terra en turment
No li membra del nostre sagrament
Que nos feimes els sans cominalment
Ben sai de ver que gaire longament
Non serai en çai pres

Suer comtessa vostre pretz sobeiran
Sal Dieus e gart la bela qu’ieu am tan
Ni per cui soi ja pres