TED演讲第14期:如何看到不可见的运动听到沉默的声音(2)（打印版）

We basically analyze the changes in the light that are recorded at every pixel in the video over time, 首先我们分析了录像中每个像素的光线随时间发生的变化，

and then we crank up those changes. 我们放大这些变化。

We make them bigger so that we can see them. 经过放大使我们肉眼可以看见这些变化。

The tricky part is that those signals, 棘手的部分是，那些信号，

those changes that we're after, are extremely subtle, 那些我们要放大的信号十分微小，

so we have to be very careful when you try to separate them from noise that always exists in videos. 所以我们必须把它们和视频中存在的噪音区分出来。

So we use some clever image processing techniques to get a very accurate measurement of the color at each pixel in the video, 所以我们应用了一些聪明的影像处理技巧精确的测量每个像素中的颜色，

and then the way the color changes over time, 然后得出颜色随时间的变化，

and then we amplify those changes. 再然后我们放大这些变化。

We make them bigger to create those types of enhanced videos, or magnified videos, 我们可以放大这些变化，增强视频、或放大视频，

that actually show us those changes. 这样就可以演示出变化。

But it turns out we can do that not just to show tiny changes in color, 事实上，我们不仅可以展示颜色的细小变化，

but also tiny motions, 同样也可以展示微小的运动，

and that's because the light that gets recorded in our cameras will change not only if the color of the object changes, 这是因为我们的摄像机不仅记录物体的颜色变化，

but also if the object moves. 同样也记录了物体的运动。

So this is my daughter when she was about two months old. 这是我女儿，那时她才两个月大。

It's a video I recorded about three years ago. 这是我三年前拍的。

And as new parents, we all want to make sure our babies are healthy, 作为初为人父母，我们要确保孩子的健康，

that they're breathing, that they're alive, of course. 当然是，确保呼吸，确保活着。

So I too got one of those baby monitors so that I could see my daughter when she was asleep. 所以我也买了个婴儿监控器这也我可以在她睡着时看到她。

And this is pretty much what you'll see with a standard baby monitor. 这是标准婴儿监控器所看到的。

You can see the baby's sleeping, but there's not too much information there. 您可以看到孩子睡着了，但没有其他信息了。

There's not too much we can see. 我们看不到更多东西。

Wouldn't it be better, or more informative, or more useful, 可不可以更好点儿，有更多信息，更有用，

if instead we could look at the view like this. 就像这样。

So here I took the motions and I magnified them 30 times, 这里我放大了运动30倍，

and then I could clearly see that my daughter was indeed alive and breathing. 这样我就可以真切地看到我女儿还活着，在呼吸。

Here is a side-by-side comparison. 这是效果对比。

So again, in the source video, in the original video, 同样，在原始视频上，

there's not too much we can see, 我们看不到什么，

but once we magnify the motions, the breathing becomes much more visible. 但是一旦我放大了运动，呼吸变得肉眼可见了。

And it turns out, there's a lot of phenomena we can reveal and magnify with our new motion microscope. 事实上，我们用我们的运动显微镜可以揭示很多现象。

We can see how our veins and arteries are pulsing in our bodies. 我们可以看到体内静脉和动脉的脉动。

We can see that our eyes are constantly moving in this wobbly motion. 我们可以看到我们的眼睛在不断运动在晃动中。

And that's actually my eye, 这实际上是我的眼睛，

and again this video was taken right after my daughter was born, 同样，这段视频拍摄于我女儿出生不久之后，

so you can see I wasn't getting too much sleep. 所以你可以看到我睡得不多。

Even when a person is sitting still, 即使当人在静止坐着，

there's a lot of information we can extract about their breathing patterns, small facial expressions. 我们也可以提取许多信息如呼吸节律，面部表情微小变化。

TED演讲 第14期:如何看到不可见的运动听到沉默的声音(2)（在线收听）

TED演讲第14期:如何看到不可见的运动听到沉默的声音(2)（在线收听）