At the bottom left corner of the video, you can see a man walking hand in hand with a child. Following him is a woman in a white jacket, holding the hand of another child.
San Diego County Sheriff's investigators say this could be Joseph McStay and his wife Summer with their two kids, crossing the border into Tijuana.
"There's a very high probability it's them,” said Sheriff's homicide Lt. Dennis Brugos.
Detectives showed the video to their family. Some recognized the white jacket that the woman is wearing in the video. But other family members aren't sure it's them because of the poor quality of the video.
"It's very grainy, overshadowed, there's no definition to shape,” said Mike McStay.
Since their disappearance, investigators say the McStays haven't used their bank accounts, credit cards or cell phones.
"They could be down there on their own volition, and just wanted to drop out for awhile, that's one theory,” said Brugos. "They could have gone down there for the evening and got into a situation they couldn't get out of."