Differentiate Line breaks and Paragraphs

Hi, Is there a way to make difference between line breaks and paragraphs, when I save a text to a database from a user input? The new line characters (\n, \r) are not too consequent to determine when did the user only one new line or more new lines. (Some clients make only \n or \r, some others make \n\r or \r\n, etc.) What I would like to do is, to format the given text into paragraphs (with <p> tag), not just insert a batch of break line (<br />) tags. Of course, I want to retain <br /> tags as well, in case of the user wrote only one new line character.