Clint Riddle at The Grand Old Game posted a list of 65 pitchers and catchers who have received an invite to Astros Spring Training. Looking at the list, it appears to be the pitchers and catchers who will be attending minor league camp. There are 10 catchers included on the list.
Assuming this list is accurate and exhaustive, there are few notable pitchers and catchers missing. My speculation would be that those missing will either be invited to big league spring training or to the pitcher/catcher mini-camp that will take place prior to minor league spring training.
Notable pitchers not listed
Kevin Chapman- Non-roster invite
Josh Zeid- Non-roster invite
Notable catchers not listed
Rene Garcia- Non-roster invite
Jason Jaramillo- Non-roster invite
Carlos Perez- Non-roster invite
Chris Wallace- Non-roster invite