The disgraced Labour MP was accused of making a movie in the most serious A category of indecency, on a device.
Judge Emma Peters said that the movie, found on a device, “depicts a number of children”.
“Some are very young, one is said to be 12-months-old,” she said. “Clearly a category-A movie.”
Joyce, 59, of Worlingworth, Suffolk was granted bail after pleading guilty at Ipswich Crown Court on Tuesday and was ordered to sign the Sex Offenders Register.
Judge Peters also instructed that a report be prepared before the Labour Party shadow minister is sentenced on August 7.
She warned Joyce that the offence crosses the custody threshold, adding that the court “takes such incidents very seriously” as they “fuel the abuse of children”
Joyce was charged under the Protection of Child Act after being arrested on in Worlingworth on November 6, 2018.
He was then released under investigation until being summonsed to appear before magistrates this week.
The MP issued a statement about his charge on his website in June.
“I will make no comment from now until all legal processes are at a close. At that point, I will make a full statement.”
The crime was said to have taken place between August 7, 2013 and November 6,2018.