Forum:Number of articles in a category from certain namespace

I'm familiar with and, but is there a way to combine them to output the amount of articles in a category from a specific namespace? Specefically I need it to count the number of File: in a category. Duskey ( talk ) 14:41, August 5, 2010 (UTC)
 * Special:Statistics and look at the line Uploaded files? -- 16:19, August 5, 2010 (UTC)