英国皇家科学院圣诞讲座：让火花飞（2014）

it releases another electron.
棒极了
Excellent.
我得击中所有的像素
So, I should be able to hit all of my pixels
让他们释放电子
and they release an electron.
然后
And then,
第四像素是图像中较亮的部分
pixel four is a particularly bright part of the image,
就需要被更多的光击中
so it gets hit with more light,
两个电子都会落到桶里
so two electrons end up in the bucket.
因此当快门关闭时
So that when the shutter is closed,
芯片读取电容电量
the chip reads the capacitor charge
来查看照片的实际亮度
to see how bright the picture actually was.
你们可以留下剩下的电子
And you can keep your additional electrons.
非常感谢 你们都是好像素
Thank you very much, you were very good pixels.
那么现在我要来数数
So, now I need to just count up
我的电容里储存了多少电量
how much charge has been stored in my capacitor.
两个 一个 一个 两个
So, I have two, one, one, two.
那么我们就能得到
So, if we then say, OK,
这是我的图片左上角的四个像素
these are the top four left-hand corner of my picture,
我们可以给图片的其余部分赋值
we can then assign numbers to the rest of a picture.
好了 现在我们看到个大数 八 这儿
And say, OK, well, we've got a large number, eight, here,
我们可以说 这儿有很多光
and we'll say, that's a lot of light.
图片的这部分有很多光
So, a lot of light is on that part of the picture.
我们可以说它是白色
So we'll say that's white.
还有一些零
Then we have zeros.
那就是说这里没有光
So we can say, well, there's not a lot of light there,
我们可以当作是黑色
so we'll have that as black.
中间的剩余部分都是灰度
And then everything else is a greyscale in the middle.
分别设置好图片剩余部分的灰度后
So that when we assign a greyscale to the rest of our image,
我们就看到了亚历山大·格拉汉姆·贝尔
we get back Alexander Graham Bell.
这是黑白的 而我们生活的世界是彩色的
Now, this is black and white, and we live in a world of colour
所以我们的相机里有滤镜
so we've got filters in our cameras
覆盖在像素之上
that are placed over the pixels.
有红色 绿色和蓝色
In red, green and blue.
当你结合所有数据
And when you combine all of that data,
相机就能准确地判断出
the cameras can make a pretty good guess
主色调
at which is the dominant colour.
这就是数码相机运作的基本原理
And that's basically how digital cameras work.
数百万个微型光探测器
Millions of tiny light detectors
组成了一个复杂的传感器
to make one sophisticated sensor.
如果我们把手♥机♥当作是一个光探测器
And if we think of our phone as a light detector,
那是不是就可以开♥发♥一些其他用途呢
can we think about using our phone camera in other ways?
我们能不能用我们的摄像头
Can we use our camera to
来拍摄近景特写镜头呢
take extreme close-up photography?
在此之前
Well, to show you that,
我会先向大家展示一个简单的技巧
I'm going to show you a very, very simple hack,
不过我要先休息一下
but I'm going to have a bit of a rest.
我要走上来坐在某个人旁边
I'm going to come and have a little sit down with someone up here.
我能坐在你旁边吗
So, I'm going to come and sit next to you,
你叫什么名字
if that's OK. What's your name?
-鲁宾 -鲁宾
- Reuben. - Reuben.
鲁宾 请你帮我
OK, Reuben, you can just help me
完成这个小小的展示
with this simple little hack we have, OK?
这是一部手♥机♥
So, what we have here is our mobile phone
摄像头在这儿
and we just have our camera here, OK?
我们要做的就是
And what we're going to do
从一台一次性相机上取下镜头
is just take a lens from a disposable camera.
这是台很好很便宜的一次性相机
So, a nice, cheap disposable camera.
我们要把镜头用蓝丁胶
And then we're just going to use some Blu-Tack
粘在我们的相机上
to attach a lens on to our camera.
鲁宾 我把它给你
OK? So, if I give you this, Reuben.
好吗
Ok?
你能感觉到镜头的一面是平的
What you can feel there, you can feel one's got a flat side
而另一面稍稍凸起 感觉到了吗
and one's slightly raised. Yeah. You feel it, yeah?
我需要你做的就是蓝丁胶
What I want you to do is just take this Blu-Tack
将透镜平的那一面粘在相机镜头上
and attach the flat side to the camera lens.
我们用的是蓝丁胶
Now, we're using Blu-Tack,
但你也可以用其他东西 想用什么都行
but you can use anything. Anything you like.
显然我们不能直接往上贴
Obviously, we can't get it right on the top,
因为我们要透过它视物
cos we'll need to look through that,
所以贴在边缘就好 按压下去即可
so just around the edges, and then just press it down.
然后请你把这相机
And I want you to take that
尽可能地靠近这枚硬币
and get a close as you possibly can to that coin with the camera.
-好的 那里 你能看到吗 -能
- That's it. There. Can you see that? - Yeah.
是吗 能看到靠得多近吗
Yeah? Can you see how close in you can get?
能看清上面所有的字母
You can actually even see all of the lettering.
我来给它拍张照
So, I'm going to take a little photograph of that.
然后 我们把它举到摄像师乔斯那里
And then, if we just hold it up to Joss the cameraman here,
这样大家都能 都能看到吗
just so everyone else... Can everyone see that?
伊丽莎白
看看我们靠得多近
See how close we've managed to get to it?
可以看清硬币上的小字
So you can actually see all the writing on the coin.
如果你不加上镜头 你会发现
And if you try that without the lens, you'll find you can't go
是看不到这么小的东西的
anywhere near that sort of level of information.
谢谢你的帮助
Thank you very much for your help.
这是你在家就能做到的简单小把戏
Now, that's just a nice, easy simple hack that you can do at home.
这样的摄像头拍平面照片是很好用的
Now, cameras like this are very useful for taking 2D images.
但如果我拍一匹马的照片
If I take a photograph of a horse,
我的手♥机♥并不知道这是一匹马的照片
my phone doesn't know it's a photograph of a horse,
它只能识别这是一系列像素点 即图像元素
it just knows it's a series of pixels, or picture elements.
那么 如果我们用一台相机上的
So, if we build a hologram
高分辨率图片构建一幅全息影像
from high resolution pictures on a camera,
电脑就需要
the computer needs to be able
以某种方式来处理图像
to start to process that image in some way
并对图片中的场景进行初步判断
and make some simple judgments about that scene.
我们需要将人像从背景中分离出来
We need to be able to separate the person from their background.
这样才能得到达拉斯清晰的全息影像
So we get a nice clean hologram of Dallas.
为了达到目标我们可以这么玩
Now here's a hack that can do just that.
但你绝对不能在家玩这个
But this is one hack you really, really shouldn't try at home.
实际上 这很危险
In fact, this one is so dangerous,
我们都不能在剧院里演示
we can't even do it in the lecture theatre.
由于很危险 我不能让你们来帮忙
It's so risky that I can't ask even any of you to volunteer,
所以这将由制♥作♥团队之一进行演示
so one of the production team has volunteered,
请欢迎制♥作♥团队的露西
so please welcome the production team, Lucy.
-你好 露西 -你好 丹妮尔
- Hi Lucy. - Hi, Danielle.
你感觉如何
How are you feeling?
我得承认我有点紧张
Got to admit, I'm a little bit nervous
但我相信科学
but I am going to put my trust in science.
好 我们喜欢听这样的话
Good. That's what we like to hear.
那就请你下场准备一下 露西
OK, so if you want to go off and get yourself ready, Lucy.
我说过这在剧院里演示都很危险
OK, now, as I said, it's too risky even to do in the theatre
所以现在摄像师乔跟着我走
so what's going to happen now is, if Joe the cameraman follows me
大家在大屏幕上观看
and you guys can watch on the big screen,
我们现在去后台
what's going to happen is we're going to go backstage
然后我们会看到
and we're going to see the firing range
在这里我们搭建了一个射击场
that we've set up back here.
谢谢 我还需要戴上护目镜
And, thank you, I'm going to need my safety goggles as well.
我们来看看都有些什么
So, let's see what we have.
-你好 萨沙 -你好 丹妮尔
- So, hi, Sacha. - Hi, Danielle.
谢谢你为我们做演示
Thank you very much for showing us this.
这里的两把彩弹枪经过改装
So, what we can see is two paint-ball guns that have been hacked
与两个自动塔台相连
and they're attached to two motorised turrets here.
两把枪都可以每秒连发十弹
And both of these guns are capable of firing ten balls a second.
现在我要站远一些
So, if I stand well back,
让萨沙为我们演示它们的作用
Sacha is going to show us what they can do.
我可不喜欢站在这些前面
Now, I wouldn't like to be standing in front of those.
但即使这么做应该也是安全的
But if I did, I should be safe because,
因为与这台设备相连的
attached to this rig is just an ordinary webcam
是与电脑连接的普通网络摄像头
which is attached to computer.
这台电脑分♥析♥图像找出人体轮廓后
Now, this computer analyses the screen for the shape of a human body
会控制枪避开那块板上的特定部位
and tells the guns which areas to avoid on that board.
-露西在哪儿呢 -我在这儿
- So, where's Lucy? - I'm here.