Cod is only good if it is flash frozen at the point of harvest;
Salmon is only good if it is wild caught and eaten within one or two days of harvest, (usually not obtainable in the lower 48, except CA, WA and OR)
The best Cod is the Pacific variety;
The best Salmon are Wild Caught are in preference 1) Alaskan, 2) Washington State Sockeye (Red) and Chinook (King), followed by Coho (Silver);
Chum (Dog) and Pink (Humpy) salmon are pretty much dog food.
Perhaps in a perfectionist world
In our world, the cod and the salmon filets can be cut into about 12 portions per package of 2 filets and then bagged and frozen.
Although they may not be Haute Cuisine, they are very good when cooked in a variety of ways.