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See invisible motion, hear silent sounds. Cool? Creepy? We can't decide

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    So over the past few centuries,
    microscopes have revolutionized our world.
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    They revealed to us a tiny world
    of objects, life and structures
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    that are too small for us
    to see with our naked eyes.
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    They are a tremendous contribution
    to science and technology.
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    Today I'd like to introduce you
    to a new type of microscope,
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    a microscope for changes.
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    It doesn't use optics
    like a regular microscope
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    to make small objects bigger,
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    but instead it uses a video camera
    and image processing
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    to reveal to us the tiniest motions
    and color changes in objects and people,
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    changes that are impossible
    for us to see with our naked eyes.
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    And it lets us look at our world
    in a completely new way.
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    So what do I mean by color changes?
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    Our skin, for example,
    changes its color very slightly
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    when the blood flows under it.
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    That change is incredibly subtle,
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    which is why, when you
    look at other people,
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    when you look at the person
    sitting next to you,
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    you don't see their skin
    or their face changing color.
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    When we look at this video of Steve here,
    it appears to us like a static picture,
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    but once we look at this video
    through our new, special microscope,
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    suddenly we see
    a completely different image.
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    What you see here are small changes
    in the color of Steve's skin,
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    magnified 100 times
    so that they become visible.
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    We can actually see a human pulse.
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    We can see how fast
    Steve's heart is beating,
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    but we can also see the actual way
    that the blood flows in his face.
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    And we can do that not just
    to visualize the pulse,
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    but also to actually
    recover our heart rates,
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    and measure our heart rates.
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    And we can do it with regular cameras
    and without touching the patients.
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    So here you see the pulse and heart rate
    we extracted from a neonatal baby
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    from a video we took
    with a regular DSLR camera,
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    and the heart rate measurement we get
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    is as accurate as the one you'd get
    with a standard monitor in a hospital.
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    And it doesn't even have to be
    a video we recorded.
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    We can do it essentially
    with other videos as well.
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    So I just took a short clip
    from "Batman Begins" here
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    just to show Christian Bale's pulse.
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    (Laughter)
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    And you know, presumably
    he's wearing makeup,
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    the lighting here is kind of challenging,
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    but still, just from the video,
    we're able to extract his pulse
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    and show it quite well.
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    So how do we do all that?
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    We basically analyze the changes
    in the light that are recorded
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    at every pixel in the video over time,
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    and then we crank up those changes.
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    We make them bigger
    so that we can see them.
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    The tricky part is that those signals,
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    those changes that we're after,
    are extremely subtle,
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    so we have to be very careful
    when you try to separate them
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    from noise that always exists in videos.
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    So we use some clever
    image processing techniques
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    to get a very accurate measurement
    of the color at each pixel in the video,
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    and then the way the color
    changes over time,
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    and then we amplify those changes.
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    We make them bigger to create those types
    of enhanced videos, or magnified videos,
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    that actually show us those changes.
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    But it turns out we can do that
    not just to show tiny changes in color,
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    but also tiny motions,
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    and that's because the light
    that gets recorded in our cameras
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    will change not only if the color
    of the object changes,
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    but also if the object moves.
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    So this is my daughter
    when she was about two months old.
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    It's a video I recorded
    about three years ago.
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    And as new parents, we all want
    to make sure our babies are healthy,
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    that they're breathing,
    that they're alive, of course.
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    So I too got one of those baby monitors
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    so that I could see my daughter
    when she was asleep.
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    And this is pretty much what you'll see
    with a standard baby monitor.
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    You can see the baby's sleeping, but
    there's not too much information there.
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    There's not too much we can see.
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    Wouldn't it be better,
    or more informative, or more useful,
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    if instead we could look
    at the view like this.
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    So here I took the motions
    and I magnified them 30 times,
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    and then I could clearly see that my
    daughter was indeed alive and breathing.
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    (Laughter)
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    Here is a side-by-side comparison.
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    So again, in the source video,
    in the original video,
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    there's not too much we can see,
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    but once we magnify the motions,
    the breathing becomes much more visible.
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    And it turns out, there's
    a lot of phenomena
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    we can reveal and magnify
    with our new motion microscope.
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    We can see how our veins and arteries
    are pulsing in our bodies.
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    We can see that our eyes
    are constantly moving
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    in this wobbly motion.
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    And that's actually my eye,
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    and again this video was taken
    right after my daughter was born,
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    so you can see I wasn't getting
    too much sleep. (Laughter)
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    Even when a person is sitting still,
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    there's a lot of information
    we can extract
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    about their breathing patterns,
    small facial expressions.
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    Maybe we could use those motions
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    to tell us something about
    our thoughts or our emotions.
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    We can also magnify small
    mechanical movements,
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    like vibrations in engines,
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    that can help engineers detect
    and diagnose machinery problems,
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    or see how our buildings and structures
    sway in the wind and react to forces.
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    Those are all things that our society
    knows how to measure in various ways,
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    but measuring those motions is one thing,
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    and actually seeing those
    motions as they happen
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    is a whole different thing.
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    And ever since we discovered
    this new technology,
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    we made our code available online so that
    others could use and experiment with it.
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    It's very simple to use.
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    It can work on your own videos.
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    Our collaborators at Quanta Research
    even created this nice website
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    where you can upload your videos
    and process them online,
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    so even if you don't have any experience
    in computer science or programming,
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    you can still very easily experiment
    with this new microscope.
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    And I'd like to show you
    just a couple of examples
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    of what others have done with it.
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    So this video was made by
    a YouTube user called Tamez85.
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    I don't know who that user is,
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    but he, or she, used our code
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    to magnify small belly
    movements during pregnancy.
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    It's kind of creepy.
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    (Laughter)
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    People have used it to magnify
    pulsing veins in their hands.
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    And you know it's not real science
    unless you use guinea pigs,
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    and apparently this guinea pig
    is called Tiffany,
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    and this YouTube user claims
    it is the first rodent on Earth
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    that was motion-magnified.
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    You can also do some art with it.
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    So this video was sent to me
    by a design student at Yale.
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    She wanted to see
    if there's any difference
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    in the way her classmates move.
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    She made them all stand still,
    and then magnified their motions.
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    It's like seeing
    still pictures come to life.
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    And the nice thing with
    all those examples
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    is that we had nothing to do with them.
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    We just provided this new tool,
    a new way to look at the world,
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    and then people find other interesting,
    new and creative ways of using it.
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    But we didn't stop there.
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    This tool not only allows us
    to look at the world in a new way,
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    it also redefines what we can do
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    and pushes the limits of what
    we can do with our cameras.
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    So as scientists, we started wondering,
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    what other types of physical phenomena
    produce tiny motions
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    that we could now use
    our cameras to measure?
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    And one such phenomenon
    that we focused on recently is sound.
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    Sound, as we all know,
    is basically changes
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    in air pressure that
    travel through the air.
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    Those pressure waves hit objects
    and they create small vibrations in them,
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    which is how we hear
    and how we record sound.
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    But it turns out that sound
    also produces visual motions.
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    Those are motions
    that are not visible to us
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    but are visible to a camera
    with the right processing.
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    So here are two examples.
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    This is me demonstrating
    my great singing skills.
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    (Singing)
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    (Laughter)
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    And I took a high-speed video
    of my throat while I was humming.
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    Again, if you stare at that video,
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    there's not too much
    you'll be able to see,
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    but once we magnify the motions 100 times,
    we can see all the motions and ripples
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    in the neck that are involved
    in producing the sound.
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    That signal is there in that video.
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    We also know that singers
    can break a wine glass
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    if they hit the correct note.
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    So here, we're going to play a note
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    that's in the resonance
    frequency of that glass
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    through a loudspeaker that's next to it.
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    Once we play that note
    and magnify the motions 250 times,
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    we can very clearly see
    how the glass vibrates
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    and resonates in response to the sound.
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    It's not something you're used
    to seeing every day.
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    But this made us think.
    It gave us this crazy idea.
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    Can we actually invert this process
    and recover sound from video
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    by analyzing the tiny vibrations
    that sound waves create in objects,
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    and essentially convert those
    back into the sounds that produced them.
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    In this way, we can turn
    everyday objects into microphones.
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    So that's exactly what we did.
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    So here's an empty bag of chips
    that was lying on a table,
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    and we're going to turn that
    bag of chips into a microphone
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    by filming it with a video camera
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    and analyzing the tiny motions
    that sound waves create in it.
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    So here's the sound
    that we played in the room.
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    (Music: "Mary Had a Little Lamb")
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    And this is a high-speed video
    we recorded of that bag of chips.
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    Again it's playing.
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    There's no chance you'll be able
    to see anything going on in that video
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    just by looking at it,
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    but here's the sound we were able
    to recover just by analyzing
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    the tiny motions in that video.
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    (Music: "Mary Had a Little Lamb")
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    I call it -- Thank you.
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    (Applause)
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    I call it the visual microphone.
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    We actually extract audio signals
    from video signals.
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    And just to give you a sense
    of the scale of the motions here,
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    a pretty loud sound will cause that bag
    of chips to move less than a micrometer.
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    That's one thousandth of a millimeter.
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    That's how tiny the motions are
    that we are now able to pull out
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    just by observing how light
    bounces off objects
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    and gets recorded by our cameras.
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    We can recover sounds
    from other objects, like plants.
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    (Music: "Mary Had a Little Lamb")
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    And we can recover speech as well.
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    So here's a person speaking in a room.
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    Voice: Mary had a little lamb
    whose fleece was white as snow,
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    and everywhere that Mary went,
    that lamb was sure to go.
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    Michael Rubinstein: And here's
    that speech again recovered
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    just from this video
    of that same bag of chips.
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    Voice: Mary had a little lamb
    whose fleece was white as snow,
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    and everywhere that Mary went,
    that lamb was sure to go.
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    MR: We used "Mary Had a Little Lamb"
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    because those are said to be
    the first words
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    that Thomas Edison spoke
    into his phonograph in 1877.
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    It was one of the first sound
    recording devices in history.
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    It basically directed the sounds
    onto a diaphragm
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    that vibrated a needle that essentially
    engraved the sound on tinfoil
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    that was wrapped around the cylinder.
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    Here's a demonstration of recording and
    replaying sound with Edison's phonograph.
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    (Video) Voice: Testing,
    testing, one two three.
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    Mary had a little lamb
    whose fleece was white as snow,
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    and everywhere that Mary went,
    the lamb was sure to go.
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    Testing, testing, one two three.
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    Mary had a little lamb
    whose fleece was white as snow,
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    and everywhere that Mary went,
    the lamb was sure to go.
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    MR: And now, 137 years later,
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    we're able to get sound
    in pretty much similar quality
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    but by just watching objects
    vibrate to sound with cameras,
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    and we can even do that when the camera
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    is 15 feet away from the object,
    behind soundproof glass.
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    So this is the sound that we were
    able to recover in that case.
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    Voice: Mary had a little lamb
    whose fleece was white as snow,
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    and everywhere that Mary went,
    the lamb was sure to go.
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    MR: And of course, surveillance is
    the first application that comes to mind.
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    (Laughter)
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    But it might actually be useful
    for other things as well.
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    Maybe in the future, we'll be able
    to use it, for example,
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    to recover sound across space,
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    because sound can't travel
    in space, but light can.
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    We've only just begun exploring
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    other possible uses
    for this new technology.
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    It lets us see physical processes
    that we know are there
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    but that we've never been able
    to see with our own eyes until now.
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    This is our team.
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    Everything I showed you today
    is a result of a collaboration
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    with this great group
    of people you see here,
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    and I encourage you and welcome you
    to check out our website,
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    try it out yourself,
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    and join us in exploring
    this world of tiny motions.
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    Thank you.
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    (Applause)
Title:
See invisible motion, hear silent sounds. Cool? Creepy? We can't decide
Speaker:
Michael Rubinstein
Description:

Meet the “motion microscope,” a video-processing tool that plays up tiny changes in motion and color impossible to see with the naked eye. Video researcher Michael Rubinstein plays us clip after jaw-dropping clip showing how this tech can track an individual’s pulse and heartbeat simply from a piece of footage. Watch him recreate a conversation by amplifying the movements from sound waves bouncing off a bag of chips. The wow-inspiring and sinister applications of this tech you have to see to believe.

more » « less
Video Language:
English
Team:
closed TED
Project:
TEDTalks
Duration:
13:18
  • 108
    00:05:30,708 --> 00:05:33,901
    Our collaborators at Quantum Research
    even created this nice website
    ->
    Our collaborators at Quanta Research
    even created this nice website
    # See https://videoscope.qrilab.com/

    114
    00:05:48,470 --> 00:05:53,787
    So this video was made by
    a YouTube user called Tamez85.
    ->
    So this video was made by
    a YouTube user called Tomez85.
    # See https://www.youtube.com/user/Tomez85

  • 237
    00:12:39,157 --> 00:12:42,176
    other possible uses
    for this new technology.
    ->
    all the possible uses
    for this new technology.

English subtitles

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