Mr Ellis was found dead at his home in Portadown's Clounagh Park on Monday December 9.
Police said they had received 'critical information' from the public and after a post mortem, a murder investigation was launched.
Two men, aged 18 and 24, were arrested last Saturday and last night were charged with murder.
Both men are due to appear at Armagh Magistrates Court today, Tuesday 17th December.
Detective Chief Inspector Eamonn Corrigan from PSNI's Major Investigation Team said: " At this point I would also like to thank the local community for all of the invaluable information they have provided to my detectives to date, however we still need people to get in touch and tell us what they know so we can establish exactly what happened. We are releasing an image of Mr Ellis in hopes it will spark a memory in someone and bring forth some information that could assist our investigation.
"If you were in Clounagh Park between 10:30 pm on Sunday 8 December and 9:45am on Monday 9 December please search your memory and think back on what you saw or heard during that time. You can get in touch with the investigation team by calling 101 quoting reference number 414 of 09/12/19.
""Alternatively information can also be provided by calling the independent charity Crimestoppers on 0800 555 111."