Question: Who directed the film Ray Parker Jr is best known for writing and performing the theme song to?

Context paragraphs:
A Woman Needs Love (Just Like You Do): "A Woman Needs Love (Just Like You Do)" is a 1981 song recorded by American R&B vocalist and songwriter Ray Parker Jr., along with his group, Raydio.  It led their 1981 album, "A Woman Needs Love", the last Parker recorded with Raydio.  The song was a hit on both the "Billboard" pop and soul charts in early 1981.  It was Parker's first song to hit number-one on the R&B chart, and also reached number four on the "Billboard" Hot 100.  It is ranked as the 16th biggest U.S. hit of 1981.

That Old Song: "That Old Song" is a 1981 song recorded by American R&B vocalist and songwriter Ray Parker Jr., along with his group, Raydio.  It was the third of four single releases from their 1981 album, "A Woman Needs Love", the last Parker recorded with Raydio.  It was the second biggest hit from the album, after "A Woman Needs Love (Just Like You Do)."

Ray Parker Jr.: Ray Erskine Parker Jr. (born May 1, 1954) is an American guitarist, singer-songwriter,  record producer, and actor, best known for writing and performing the theme song to the movie "Ghostbusters", for his solo music, and for performing with his band, Raydio, and with Barry White.

I'm Free (album): I'm Free is the sixth and (for now) final solo album by guitarist/singer/songwriter Ray Parker Jr..  He made a comeback after 15 years of absence with this album released from his own independent record company called "Raydio Music Inc.".  The record was released in 2006 and included the song "Mexico".

Raydio: Raydio was an American funk and R&B vocal group formed in 1977, by Ray Parker Jr., with Vincent Bohnam, Jerry Knight, and Arnell Carmichael.

You See the Trouble with Me: "You See the Trouble with Me" is a song recorded by American soul artists Barry White and Ray Parker Jr..  It was released in February 1976 as the second single from White's album "Let the Music Play".  In its initial release, the track reached number 14 on Billboard's Black Singles chart, and number 2 in the UK.

The Other Woman (song): "The Other Woman" is the title track from a 1982 album of the same name by Ray Parker Jr..  It was his first hit single without his longtime group, Raydio.  Released as a single in March 1982, it peaked at number four on the "Billboard" Hot 100, number two on the Hot Black Singles chart, number twenty-four on the dance chart, and number thirty-three on the Adult Contemporary chart.  Overseas, it spent one week at number one on the Australian charts.

Ghostbusters: Ghostbusters is a 1984 American supernatural comedy film directed and produced by Ivan Reitman and written by Dan Aykroyd and Harold Ramis.  The film stars Bill Murray, Aykroyd and Ramis as eccentric parapsychologists who start a ghost-catching business in New York City.  Sigourney Weaver and Rick Moranis co-star as a client and her neighbor, and Ernie Hudson as the Ghostbusters' first recruit.

Who Ya Gonna Call?: "Who Ya Gonna Call?"  is the seventh episode of the first season of the American comedy-drama television series "Psych".  It was written by co-executive producers Jack Sakmar and Kerry Lenhart, and was directed by Michael Lange.  The episode originally aired on USA Network in the United States on August 18, 2006.  The installment features guest appearances by Kirsten Nelson, Sage Brocklebank, Frank Whaley, and Nico McEown among others.  The title refers to the song "Ghostbusters", written and performed by Ray Parker Jr.

Enemy Territory (film): Enemy Territory is a 1987 American action film.  The film stars Gary Frank, Ray Parker Jr., and Jan-Michael Vincent.  The film is about an insurance salesman who inadvertently gets trapped in a New York City public housing apartment building that is controlled and terrorized by a local street gang.  The film was released on May 22, 1987 by Empire Pictures.

Supporting paragraphs: Ray Parker Jr. Ghostbusters
Answer: Ivan Reitman