If you did not have backups and you already tried recovery apps, you have no way of getting them back. But the cache should not contain your pictures, what cache did you delete? Were these temporary pictures you did not actually save somewhere? A cache is basically a temporary storage place to be used for data that can be discarded at a later time. Photos would not be saved to any cache normally, unless you happened to delete the cache of some 3rd party program that was storing your files.