Add Movie Once, But Trim It Three Times

[kurvball]

I have a 30-minute movie (dvr-ms file) that contains three separate 7-minute shows with commercials in between. From this movie, I would like to create three separate 7-minute long mpeg files.

 

As it is right now, I have to load the 30-minute movie to Copy & Convert tool, then trim it down to one of the 7-minute movies, and convert it to mpeg. I then have to remove the 30-minute movie that has been trimmed from the Copy & Convert tool and then reload the original 30-minute movie again in order to create the second 7-minute long mpeg file. And then do the whole process again for the third 7-minute long mpeg file.

 

Is there anyway to do this without having to load the 30-minute movie three separate times? For instance, after I've created the first 7-minute movie, can I then remove the trimming that I did, and then retrim for the second 7-minute movie? I'm just trying to avoid having to reload that 30-minute movie three times (trying to save some time).