If indicating sort direction without utilizing more horizontal space is a requirement, your main option is to utilize more vertical space to display sort direction.
Other things you may wish to consider, however:
Analyze your columns and only show the most important/relevant sections. You may wish to remove certain items from the main table view to gain more space. If the items in your table are clickable and go to a detailed view, maybe you can show view/download count in the detailed view instead. It seems like the most important metric for sorting titles will be rating, and I'm not sure that the view count really tells the end user very much about the quality of the item.
Maybe it's not important to indicate sort direction. If your title columns indicate that they are clickable by using the same styling as all your other links I don't see much of an advantage to adding the sort direction arrow. If a user clicks a column item once and sees the list rearrange, but the order is not what they desire, it makes sense they would click it again until the order is correct, since they know clicking the link rearranges the list.
Maybe you can implement a single sort direction solution, based on whichever sort direction makes the most sense for each item. Clicking title or author rearranges the list alphabetically ascending, clicking rating rearranges the list numerically (or by stars) descending, etc. Is anyone ever going to want to sort by lowest rating? If not highest rating should be default. This can simplify the whole process. You click a column, the table is sorted whichever direction it makes sense to sort by (based on the column you clicked), and the column is highlighted temporarily (maybe with a color fade in/out) to indicate that an action was just taken based on the clicked item.