TEDGlobal 2012
Ramesh Raskar: Imaging at a trillion frames per second
Ramesh Raskar: Snemanje pri bilijonu sličic na sekundo
Filmed:
Readability: 4
5,395,201 views
Ramesh Raskar predstavi femto-fotografijo, nov in tako hiter način snemanja, da svet prikaže pri bilijonu sličic na sekundo, ter tako podroben, da prikaže svetlobo v gibanju. S to tehnologijo bo morda nekoč mogoče snemati “okrog vogala” ali gledati v telo brez rentgenskih žarkov.
Ramesh Raskar - Femto-photographer
Photography is about creating images by recording light. At the MIT media lab, professor Ramesh Raskar and his team members have invented a camera that can photograph light itself as it moves at, well, the speed of light. Full bio
Photography is about creating images by recording light. At the MIT media lab, professor Ramesh Raskar and his team members have invented a camera that can photograph light itself as it moves at, well, the speed of light. Full bio
Double-click the English transcript below to play the video.
00:16
Doc Edgerton inspired us with awe and curiosity
0
902
5978
Doc Edgerton je v nas vzbudil
čudenje in radovednost
čudenje in radovednost
00:22
with this photo of a bullet piercing through an apple,
1
6880
5262
s to sliko izstrelka,
ki prodira skozi jabolko
ki prodira skozi jabolko
00:28
and exposure just a millionth of a second.
2
12142
4878
pri osvetlitvi milijoninke sekunde.
00:32
But now, 50 years later, we can go a million times faster
3
17020
7307
50 let kasneje smo lahko
milijonkrat hitrejši
milijonkrat hitrejši
00:40
and see the world not at a million,
4
24327
3596
in sveta ne vidimo le pri milijonu
00:43
or a billion,
5
27923
1810
ali milijardi,
00:45
but one trillion frames per second.
6
29733
3435
temveč pri bilijonu sličic na sekundo.
00:49
I present you a new type of photography,
7
33168
4385
Predstavljam vam novo vrsto fotografije,
00:53
femto-photography,
8
37553
2059
femto-fotografijo,
00:55
a new imaging technique so fast
9
39612
4600
ki je tako hitra tehnika snemanja,
01:00
that it can create slow motion videos of light in motion.
10
44212
5201
da lahko ustvari počasne posnetke
gibanja svetlobe.
gibanja svetlobe.
01:05
And with that, we can create cameras
11
49413
2738
Izdelamo lahko kamere,
01:08
that can look around corners,
12
52151
2145
ki lahko pogledajo okrog vogala,
01:10
beyond line of sight
13
54296
1997
izven zorne linije
01:12
or see inside our body without an X-ray,
14
56293
4393
in brez rentgenskih žarkov vidijo
v notranjost telesa
v notranjost telesa
01:16
and really challenge what we mean by a camera.
15
60686
5401
ter izrazu kamera dajejo nov pomen.
01:21
Now if I take a laser pointer and turn it on and off
16
66087
3511
Če vzamem lasersko kazalko in jo vključim
01:25
in one trillionth of a second --
17
69598
2827
za bilijoninko sekunde,
01:28
which is several femtoseconds --
18
72425
2812
kar je nekaj femtosekund,
01:31
I'll create a packet of photons
19
75237
2280
ustvarim paket fotonov,
01:33
barely a millimeter wide,
20
77517
2350
ki je širok zgolj milimeter.
01:35
and that packet of photons, that bullet,
21
79867
2926
Ta paket fotonov oziroma izstrelek
01:38
will travel at the speed of light,
22
82793
1950
bo potoval s svetlobno hitrostjo,
01:40
and, again, a million times faster than an ordinary bullet.
23
84743
4508
milijonkrat hitreje kot navaden izstrelek.
01:45
Now, if you take that bullet and take this packet of photons
24
89251
4906
Če ta izstrelek oziroma paket fotonov
01:50
and fire into this bottle,
25
94157
3173
izstrelim v plastenko –
01:53
how will those photons shatter into this bottle?
26
97330
4534
kako se bodo fotoni razpršili v plastenki?
01:57
How does light look in slow motion?
27
101864
4224
Kako je videti svetloba
v počasnem posnetku?
v počasnem posnetku?
02:21
Now, the whole event -- (Applause)
28
126041
3658
Celoten dogodek – (Aplavz)
02:25
(Applause)
29
129699
4219
(Aplavz)
02:29
Now, remember, the whole event
30
133918
2603
Torej, celoten dogodek
02:32
is effectively taking place in less than a nanosecond
31
136521
3383
se odvije v manj kot nanosekundi,
02:35
— that's how much time it takes for light to travel —
32
139904
2336
kar je čas, ki ga svetloba
potrebuje za to pot,
potrebuje za to pot,
02:38
but I'm slowing down in this video by a factor of 10 billion
33
142240
4500
vendar je posnetek upočasnjen
z večkratnikom 10 milijard,
z večkratnikom 10 milijard,
02:42
so you can see the light in motion.
34
146740
3673
da lahko vidite svetlobo v gibanju.
02:46
But, Coca-Cola did not sponsor this research. (Laughter)
35
150413
4621
Coca-Cola ni sponzor teh raziskav. (Smeh)
02:50
Now, there's a lot going on in this movie,
36
155034
2047
Na tem posnetku se veliko dogaja,
02:52
so let me break this down and show you what's going on.
37
157081
2362
zato bom opisal korake in vam povedal, za kaj gre.
02:55
So, the pulse enters the bottle, our bullet,
38
159443
3240
Utrip svetlobe, naš izstrelek,
vstopi v plastenko
vstopi v plastenko
02:58
with a packet of photons that start traveling through
39
162683
2562
kot paket fotonov,
ki pričnejo svojo pot skozi
ki pričnejo svojo pot skozi
03:01
and that start scattering inside.
40
165245
1837
in ki se začnejo v notranjosti sipati.
03:02
Some of the light leaks, goes on the table,
41
167082
2231
Nekaj svetlobe uide ven in gre na mizo,
03:05
and you start seeing these ripples of waves.
42
169313
2787
zato opazite to valovanje.
03:08
Many of the photons eventually reach the cap
43
172100
2881
Kar nekaj fotonov končno doseže pokrovček
03:10
and then they explode in various directions.
44
174981
2914
in jih tam raznese v različne smeri.
03:13
As you can see, there's a bubble of air,
45
177895
1912
Vidite lahko zračni mehurček
03:15
and it's bouncing around inside.
46
179807
1666
in kako se v njem odbija.
03:17
Meanwhile, the ripples are traveling on the table,
47
181473
2474
Medtem valovanje potuje po mizi,
03:19
and because of the reflections at the top,
48
183947
1869
zaradi odboja na vrhu
03:21
you see at the back of the bottle, after several frames,
49
185816
3634
pa se na dnu plastenke po nekaj sličicah
03:25
the reflections are focused.
50
189450
2902
odboji osredotočijo.
03:28
Now, if you take an ordinary bullet
51
192352
5894
Če bi vzeli navaden izstrelek,
03:34
and let it go the same distance and slow down the video
52
198246
3401
ga spustili čez enako razdaljo
in posnetek upočasnili
in posnetek upočasnili
03:37
again by a factor of 10 billion, do you know
53
201647
2549
prav tako s faktorjem 10 milijard
– ali veste,
– ali veste,
03:40
how long you'll have to sit here to watch that movie?
54
204196
5725
kako dolgo bi sedeli tu,
da bi si ga ogledali?
da bi si ga ogledali?
03:45
A day, a week? Actually, a whole year.
55
209921
4388
En dan, en teden? Trajalo bi celo leto.
03:50
It'll be a very boring movie — (Laughter) —
56
214309
3914
To bi bil zelo dolgočasen posnetek (Smeh)
03:54
of a slow, ordinary bullet in motion.
57
218223
4052
počasnega, navadnega izstrelka v gibanju.
03:58
And what about some still-life photography?
58
222275
4603
Kaj pa fotografija tihožitja?
04:08
You can watch the ripples again washing over the table,
59
232770
5352
Spet lahko vidite valovanje,
ki preplavi mizo,
ki preplavi mizo,
04:14
the tomato and the wall in the back.
60
238122
2913
paradižnik in steno v ozadju.
04:16
It's like throwing a stone in a pond of water.
61
241035
4224
Kot bi v vodo vrgli kamen.
04:23
I thought, this is how nature paints a photo,
62
247197
3890
Narava na tak način naslika fotografijo,
04:26
one femto frame at a time,
63
251087
2587
eno femto sličico za drugo,
04:29
but of course our eye sees an integral composite.
64
253674
5392
a naše oko vidi
celovito sestavljeno sliko.
celovito sestavljeno sliko.
04:34
But if you look at this tomato one more time,
65
259066
3126
Če še enkrat pogledate paradižnik,
04:38
you will notice, as the light washes over the tomato,
66
262192
2516
boste videli, da potem,
ko ga preplavi svetloba,
ko ga preplavi svetloba,
04:40
it continues to glow. It doesn't become dark.
67
264708
2891
še naprej sije. Ne zatemni se.
04:43
Why is that? Because the tomato is actually ripe,
68
267599
3548
Zakaj? Paradižnik je dejansko zrel
04:47
and the light is bouncing around inside the tomato,
69
271147
2101
in svetloba se znotraj njega odbija,
04:49
and it comes out after several trillionths of a second.
70
273248
4466
ven pa pride po nekaj
bilijoninkah sekunde.
bilijoninkah sekunde.
04:53
So, in the future, when this femto-camera
71
277714
2633
Ko boste v prihodnosti to femto-kamero
04:56
is in your camera phone,
72
280347
2092
imeli v svojem mobilnem telefonu,
04:58
you might be able to go to a supermarket
73
282439
1710
boste lahko v trgovini
05:00
and check if the fruit is ripe without actually touching it.
74
284149
4040
preverjali zrelost sadežev
ne da bi se jih dotaknili.
ne da bi se jih dotaknili.
05:04
So how did my team at MIT create this camera?
75
288189
5330
In kako smo z ekipo na MIT
izdelali to kamero?
izdelali to kamero?
05:09
Now, as photographers, you know,
76
293519
1967
Fotograf ve,
05:11
if you take a short exposure photo, you get very little light,
77
295486
4061
da pri kratki osvetlitvi dobimo
le malo svetlobe,
le malo svetlobe,
05:15
but we're going to go a billion times faster
78
299547
2206
mi pa snemamo
pri milijardokrat večji hitrosti
pri milijardokrat večji hitrosti
05:17
than your shortest exposure,
79
301753
1856
kot je najkrajša osvetlitev,
05:19
so you're going to get hardly any light.
80
303609
1800
tako da dobimo komaj kaj svetlobe.
05:21
So, what we do is we send that bullet,
81
305409
1843
Naredimo tako, da pošljemo izstrelke,
05:23
those packet of photons, millions of times,
82
307252
2549
te pakete fotonov, milijonkrat
05:25
and record again and again with very clever synchronization,
83
309801
3107
in jih posnamemo znova in znova,
jih domiselno uskladimo
jih domiselno uskladimo
05:28
and from the gigabytes of data,
84
312908
2091
in potem iz gigabajtov podatkov,
05:30
we computationally weave together
85
314999
2116
ki jih računsko stkemo skupaj,
05:33
to create those femto-videos I showed you.
86
317115
3465
ustvarimo te femto-posnetke.
05:36
And we can take all that raw data
87
320580
2540
Surove podatke zberemo
05:39
and treat it in very interesting ways.
88
323120
2895
in jih obdelamo na zanimive načine.
05:41
So, Superman can fly.
89
326015
1841
Superman lahko poleti.
05:43
Some other heroes can become invisible,
90
327856
2462
Nekateri drugi junaki
lahko postanejo nevidni,
lahko postanejo nevidni,
05:46
but what about a new power for a future superhero:
91
330318
5098
morda pa bi kak drug super junak lahko
05:51
to see around corners?
92
335416
2498
gledal okrog vogalov?
05:53
The idea is that we could shine some light on the door.
93
337914
4673
Zamisel je v tem, da posvetimo na vrata.
05:58
It's going to bounce, go inside the room,
94
342587
2675
Svetloba se bo odbila v sobo,
06:01
some of that is going to reflect back on the door,
95
345262
2430
nekaj se je bo odbilo nazaj na vrata,
06:03
and then back to the camera,
96
347692
1507
in potem nazaj h kameri,
06:05
and we could exploit these multiple bounces of light.
97
349199
3488
tako da bi lahko izkoristili
te večkratne odboje.
te večkratne odboje.
06:08
And it's not science fiction. We have actually built it.
98
352687
2397
To ni znanstvena fantastika,
to smo res naredili.
to smo res naredili.
06:10
On the left, you see our femto-camera.
99
355084
2384
Na levi vidite femto-kamero.
06:13
There's a mannequin hidden behind a wall,
100
357468
2379
Za steno je skrita lutka,
06:15
and we're going to bounce light off the door.
101
359847
2982
z vrati pa bomo odbili svetlobo.
06:18
So after our paper was published
102
362829
1948
Ko je bil naš članek objavljen
06:20
in Nature Communications,
103
364777
1934
v reviji Nature Communications,
06:22
it was highlighted by Nature.com,
104
366711
1915
je nanj opozorila stran Nature.com,
06:24
and they created this animation.
105
368626
2563
kjer so izdelali naslednjo animacijo.
06:27
(Music)
106
371189
6402
(Glasba)
06:33
We're going to fire those bullets of light,
107
377591
3461
Izstrelili bomo izstrelke svetlobe,
06:36
and they're going to hit this wall,
108
381052
3263
ki se bodo zadeli ob to steno,
06:40
and because the packet of the photons,
109
384315
2655
in ker gre za pakete fotonov,
06:42
they will scatter in all the directions,
110
386970
2297
se bodo ti razpršili v vse smeri,
06:45
and some of them will reach our hidden mannequin,
111
389267
2248
nekaj jih bo doseglo našo skrito lutko,
06:47
which in turn will again scatter that light,
112
391515
2879
ki bo spet razpršila svetlobo,
06:50
and again in turn the door will reflect
113
394394
3686
in potem bodo vrata odbila
06:53
some of that scattered light,
114
398080
2072
nekaj te razpršene svetlobe,
06:56
and a tiny fraction of the photons will actually
115
400152
2744
majcen del fotonov pa se bo dejansko
06:58
come back to the camera, but most interestingly,
116
402896
2284
vrnil k kameri, vendar – še posebej zanimivo –
07:01
they will all arrive at a slightly different time slot.
117
405180
3746
bodo prispeli v različnih časovnih intervalih.
07:04
(Music)
118
408926
4577
(Glasba)
07:09
And because we have a camera that can run so fast,
119
413503
2817
Ker je naša femto-kamera tako hitra,
07:12
our femto-camera, it has some unique abilities.
120
416320
3106
ima nekaj edinstvenih sposobnosti.
07:15
It has very good time resolution,
121
419426
2906
Ima izredno dobro časovno ločljivost
07:18
and it can look at the world at the speed of light.
122
422332
3518
in svet lahko vidi pri hitrosti svetlobe.
07:21
And this way, we know the distances, of course to the door,
123
425850
3545
Poznamo razdaljo do vrat
07:25
but also to the hidden objects,
124
429395
1894
in do skritih predmetov,
07:27
but we don't know which point corresponds
125
431289
1595
ne vemo pa, katera točka ustreza
07:28
to which distance.
126
432884
2322
kateri razdalji.
07:31
(Music)
127
435206
3240
(Glasba)
07:34
By shining one laser, we can record one raw photo, which,
128
438446
3944
Ko posvetimo z enim laserjem,
lahko naredimo en surov posnetek,
lahko naredimo en surov posnetek,
07:38
you look on the screen, doesn't really make any sense,
129
442390
2450
ki ni videti prav zgovoren.
07:40
but then we will take a lot of such pictures,
130
444840
1880
Ampak naredimo več takih posnetkov,
07:42
dozens of such pictures, put them together,
131
446720
2419
na ducate, in jih združimo
07:45
and try to analyze the multiple bounces of light,
132
449139
2678
ter analiziramo večkratne odboje svetlobe,
07:47
and from that, can we see the hidden object?
133
451817
3416
iz tega pa – ali lahko vidimo
skriti predmet?
skriti predmet?
07:51
Can we see it in full 3D?
134
455233
2919
Ga lahko vidimo v treh razsežnostih?
07:54
So this is our reconstruction. (Music)
135
458152
2636
Takole smo ga rekonstruirali. (Glasba)
07:56
(Music)
136
460788
3458
(Glasba)
08:00
(Music) (Applause)
137
464246
8308
(Glasba) (Aplavz)
08:08
Now we have some ways to go before we take this
138
472554
2611
Še dolga je pot, preden bomo lahko šli
08:11
outside the lab on the road, but in the future,
139
475165
3197
iz laboratorija v dejansko okolje,
a v prihodnosti
a v prihodnosti
08:14
we could create cars that avoid collisions
140
478362
2834
bi lahko izdelali avte,
ki bi se izogibali trkom
ki bi se izogibali trkom
08:17
with what's around the bend,
141
481196
2216
s predmeti izza ovinka,
08:19
or we can look for survivors in hazardous conditions
142
483412
3914
in v nevarnih okoliščinah
bi lahko iskali preživele,
bi lahko iskali preživele,
08:23
by looking at light reflected through open windows,
143
487326
4278
s tem, ko bi opazovali svetlobo,
odbito prek odprtih oken,
odbito prek odprtih oken,
08:27
or we can build endoscopes that can see
144
491604
2625
lahko pa bi izdelali endoskope,
ki bi lahko
ki bi lahko
08:30
deep inside the body around occluders,
145
494229
3270
gledali globoko v telo okrog zapor,
08:33
and also for cardioscopes.
146
497499
1876
ali kardioskope.
08:35
But of course, because of tissue and blood,
147
499375
2501
Seveda bi bilo to zaradi tkiv in krvi
08:37
this is quite challenging, so this is really a call
148
501876
2187
velik izziv, tako da je to poziv
08:39
for scientists to start thinking about femto-photography
149
504063
2853
znanstvenikom, naj začnejo
razmišljati o femtofotografiji
razmišljati o femtofotografiji
08:42
as really a new imaging modality to solve
150
506916
2589
kot novem načinu snemanja, ki bo rešitev
08:45
the next generation of health imaging problems.
151
509505
3577
za naslednjo generacijo težav
pri zdravstvenih posnetkih.
pri zdravstvenih posnetkih.
08:48
Now, like Doc Edgerton, a scientist himself,
152
513082
3881
Enako kot Doc Edgerton,
ki je bil tudi znanstvenik,
ki je bil tudi znanstvenik,
08:52
science became art, an art of ultra-fast photography,
153
516963
5176
gledam na znanost ultra-hitre fotografije
kot na umetnost
kot na umetnost
08:58
and I realized that all the gigabytes of data
154
522139
3464
in sem spoznal,
da vsi ti gigabajti podatkov,
da vsi ti gigabajti podatkov,
09:01
that we're collecting every time
155
525603
2004
ki jih vsakič zberemo,
09:03
is not just for scientific imaging, but we can also do
156
527607
3443
niso le znanstveni posnetki,
ampak lahko izdelamo
ampak lahko izdelamo
09:06
a new form of computational photography
157
531050
3780
novo vrsto računske fotografije
09:10
with time-lapse and color-coding,
158
534830
4139
s posnetki v časovnih intervalih
in z barvnim označevanjem
in z barvnim označevanjem
09:14
and we look at those ripples. Remember,
159
538969
2770
ter z njimi pogledamo valovanje.
Ne pozabite,
Ne pozabite,
09:17
the time between each of those ripples is only
160
541739
2675
da je časovna razlika med vsakim valom le
09:20
a few trillionths of a second.
161
544414
4343
nekaj bilijonink sekunde.
09:24
But there's also something funny going on here.
162
548757
1956
Pri tem pa se dogaja še nekaj čudnega.
09:26
When you look at the ripples under the cap,
163
550713
2354
Če pogledate valove pod pokrovčkom,
09:28
the ripples are moving away from us.
164
553067
3620
vidite, da se oddaljujejo.
09:32
The ripples should be moving towards us.
165
556687
2149
Morali pa bi se približevati.
09:34
What's going on here?
166
558836
1767
Kaj se dogaja?
09:36
It turns out, because we're recording
167
560603
1958
Zato, ker snemamo
09:38
nearly at the speed of light,
168
562561
4547
s skoraj svetlobno hitrostjo,
09:43
we have strange effects,
169
567108
2070
dobimo nenavadne učinke –
09:45
and Einstein would have loved to see this picture.
170
569178
4031
Einstein bi najbrž z veseljem
videl to sliko.
videl to sliko.
09:49
The order at which events take place in the world
171
573209
3269
Zaporedje, po katerem se odvijajo dogodki,
09:52
appear in the camera with sometimes reversed order,
172
576478
4568
so v kameri
v navidezno obrnjenem zaporedju,
v navidezno obrnjenem zaporedju,
09:56
so by applying the corresponding space and time warp,
173
581046
3359
ko pa prostor in čas ustrezno upognemo,
10:00
we can correct for this distortion.
174
584405
4045
lahko popačenje popravimo.
10:04
So whether it's for photography around corners,
175
588450
4241
Za vse – fotografijo izza vogala,
10:08
or creating the next generation of health imaging,
176
592691
4308
zdravstvene posnetke naslednje generacije,
10:12
or creating new visualizations,
177
596999
2680
izdelavo novih upodobitev –
10:15
since our invention, we have open-sourced
178
599679
3559
smo od odkritja naprej nudili
odprto-kodni dostop
odprto-kodni dostop
10:19
all the data and details on our website, and our hope
179
603238
3699
do vseh podatkov
na našem spletnem mestu, in upamo,
na našem spletnem mestu, in upamo,
10:22
is that the DIY, the creative and the research community
180
606937
6636
da bodo domači mojstri,
ustvarjalci in raziskovalci
ustvarjalci in raziskovalci
10:29
will show us that we should stop obsessing about
181
613573
3803
vsem pokazali, naj se nehamo gnati za
10:33
the megapixels in cameras — (Laughter) —
182
617376
3240
megapiksli v kamerah (Smeh)
10:36
and start focusing on the next dimension in imaging.
183
620616
5030
in naj se obrnemo
k naslednji razsežnosti posnetkov.
k naslednji razsežnosti posnetkov.
10:41
It's about time. Thank you. (Applause)
184
625646
4534
Nastopil je čas. (Aplavz)
10:46
(Applause)
185
630180
10205
(Aplavz)
ABOUT THE SPEAKER
Ramesh Raskar - Femto-photographerPhotography is about creating images by recording light. At the MIT media lab, professor Ramesh Raskar and his team members have invented a camera that can photograph light itself as it moves at, well, the speed of light.
Why you should listen
In 1964 MIT professor Harold Edgerton, pioneer of stop-action photography, famously took a photo of a bullet piercing an apple using exposures as short as a few nanoseconds. Inspired by his work, Ramesh Raskar and his team set out to create a camera that could capture not just a bullet (traveling at 850 meters per second) but light itself (nearly 300 million meters per second).
Stop a moment to take that in: photographing light as it moves. For that, they built a camera and software that can visualize pictures as if they are recorded at 1 trillion frames per second. The same photon-imaging technology can also be used to create a camera that can peer "around" corners , by exploiting specific properties of the photons when they bounce off surfaces and objects.
Among the other projects that Raskar is leading, with the MIT Media Lab's Camera Culture research group, are low-cost eye care devices, a next generation CAT-Scan machine and human-computer interaction systems.
Papers:
Andreas Velten, Thomas Willwacher, Otkrist Gupta, Ashok Veeraraghavan, Moungi G. Bawendi and Ramesh Raskar, “Recovering ThreeDimensional Shape around a Corner using Ultra-Fast Time-of-Flight Imaging.” Nature Communications, March 2012
Andreas Velten, Adrian Jarabo, Belen Masia, Di Wu, Christopher Barsi, Everett Lawson, Chinmaya Joshi, Diego Gutierrez, Moungi G. Bawendi and Ramesh Raskar, "Ultra-fast Imaging for Light in Motion" (in progress). http://femtocamera.info
Ramesh Raskar | Speaker | TED.com