In a video shared on Facebook, President Joe Biden‘s July 4 speech appears perhaps slower than usual and a little distorted.
Some people commenting on the post have certainly noticed this.
“If you’ve been around people with mental health issues or mental illnesses, you know what the speech of someone on medication sounds like,” one person said. “He was clearly medicated.”
“He articulates his words poorly,” someone else said.
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Comparing the video of the Facebook post with a recording of the speech posted by PBS NewsHour on Youtube, it appeared to us that the video had been edited. But we wanted to check with an expert.
Siwei Lyu, director of the University at Buffalo’s Media Forensic Lab and co-director of the school’s Center for Information Integrity, said there were “two telltale signs” that the video in the post had been edited.
In the original video, Biden’s speech lasts about eight minutes. In the video that appears in the Facebook post, his speech lasts about 10 minutes.
“It’s about 80% of the original playback sound,” Lyu said.
Additionally, he said he could hear “clear audio artifacts” suggesting the video had been edited, particularly when the crowd applauded Biden at the start of his speech.
“The applause sounds like an echo, which is the artifact caused by the time-stretching algorithm,” he said.
What does that mean? Lyu said, “The time-stretching algorithm is widely used to modify the playback speech of audio, but it tries to keep the original pitch of the sound while slowing down the tempo, so the slowed-down sound doesn’t sound like not to a slowdown of a vinyl record.”
“In my opinion,” Lyu said, “there is no doubt that the Facebook version of the video is a slowed down version of the original PBS video.”
It’s the same technique that was used to slow down a speech by House Speaker Nancy Pelosi to sound like she was articulating in 2019, he said.
We then assessed claims that Pelosi was articulating during his Pants on Fire speech.
This post gets the same rating: Pants on Fire.