Mellette, 24, was selected in the seventh-round of the 2013 draft. However, he has dealt with some knee trouble, which forced the team to place him on season-ending injured reserve last year.
Mellette wound up sitting out of the team’s first week of OTAs due to issues relating to his knee surgery.
Hamilton, 26, signed with the Cowboys as an undrafted free agent out of Prairie View A&M back in 2011. He appeared in two games for the Ravens during the 2012 season.