Guitar Oscillations Captured with iPhone 4

[@CrimsonCustomGuitars]

Seriously cool view of guitar strings vibrating from inside the instrument!

[@jamesbates4924]

Prof. Pan and his ME 303 students at Waterloo love you! :p

[@emanuelelorenzetti6940]

Actually guitar strings aren't oscillating like that (they just rock back and forth), that's an effect caused by the way your camera picks up the images from the strings. The camera takes "strips" of pixels very quickly from left to the right, so it does a sort of sampling on the vibration produced by the string. For low frequencies the framerate of the camera is sufficient to visualize the correct vibration, and you get a quite sinusoidal wave, for higher frequencies it is not and you get some strange stuff (a bad sampled signal). So, if this is not working for you, you just need to turn your phone 90 degrees (either way, it doesn't matter). And, if you want to have this explained better than I can do, search for vsauce's video about distortion. Anyway, it's a pretty awesome video

[@ealuevian]

Actually, the strings do oscillate. That's why harmonics exist.

[@Ressurrectify]

Strings do oscillate, but not like that.

[@Erklaerbaerr]

Yes they do. The idea, that a string oszillates in a Sin Wave is a simplification. In fact, there are multiple wavelength that are possible on a string of a certain length and strength. Simply speaking: A sting of length L can oszillate with a wavelength of 2L for example. This would mean that the string doesnt move at the ends where it is attached to the instrument but the middle of the sting changes from mountain (oszillating up) to a valley and back. Annother possibility is a wave, that has a point that doesnt move in the center. So the wavelength is exactly L. You get a "mountain" and a "valey" on the string whenever the Point at 1/4 L reaches full oszillation. Obviously we can continue like that, considdering more and more "non moving points" along the string shortening the Wavelength to 2/3 L, 1/2 L, 2/5 L etc. All these wavelength are possible. Depending on the instrument, the actuall wave is made up of certain percentages of these so called harmonics, causing the actual waveline to look jagged like in the video, since the multiple waves are superimposed (meaning they add their oscillation together). This causes the guitar to sound different from a piano, even though they both play the same note (say a C). The percentages of what the actual wave is made up of also changes over time, which causes a guitar to sound different right after you strike the string to when its been going for a few seconds. This can also be seen in the video since the "shape" of the wave changes over time.

[@cristo_crosta_gesu2910]

@Falthy I've got a oneplus3, Yes it does

[@jamsicat3999]

The dude litterally yeeted the phone inside the guitar lol

[@zonker1984]

I love how well this is mic-ing the guitar as well. I think someone needs to take advantage of this for a music video or something. Also, Unplugged has to be one of Clapton's best albums ever.

[@matteogriseri6513]

very nice! it's true: the video doesn't represent the actual movement (you would require ridiculously high frequency camera to capture that), but I think there is some form of aliasing going on there, maybe the camera has an imaging technique that allows some of the transverse wavelets that build up the entire wave to find themselves in apparently periodic positions, so in some way those oscillations that you can see are indeed depending on the string note!

[@TheTigero]

This happens for the same reason car wheels appear to be going backwards on TV...

[@min_808]

Hey Vsauce, Michael here

[@mauricecreator]

I am distorted.

[@CSKforlifeee]

ok, ill give it my best go on how to explain this: A rolling shutter on a camera means that the camera scans from left to right (or right to left) and not the whole frame at once. This means that while the strings are vibrating, our eyes see a blur, but the camera scans it and shows where the string was during the scan. I know its hard to comprehend but i'm sure you guys will get it. This is terrific and genius and the guitar playing was awesome! keep it up!

[@Ciaran55]

If the picture scanning acts orthogonally to the string (going from start to finish) then the waveform is actually plotted. BUT the 'frequency' (how many waves you see across the string) will vary depending on the ratio of scanning speed to string speed. ------------> Scan line 1 ------------> Scan line 2 ! | | | string | | ' ------------> Last scan line say the string completes one wave (from middle to right, right to middle, middle to left, and left to middle) in the time it takes for the scanner to complete a frame (finish the image). Assuming the wave starts as the scanner starts, at the top the string is in the middle. 1/4 of the way and the string is on the right. 2/4 of scanning completed and the string is back in the middle. 3/4, the string is on the left, and 4/4, back in the middle. If the scanner speed was now doubled, you would only see the first half of the wave. If the scanner speed was halved, then at half way the string would already have completed a wave, meaning you would see two waves. Theoretically, if the wave was faster than the scanner speed (while still being visible as a continuous wave, and not blurred) but not so fast that a whole wave could not be represented clearly (e..g. a whole wave occurring every scan line or faster), AND the vibration of the string died out before the scanner finished the image, you would see a continuous, decaying waveform that represents the actual sound (albeit without a guide to the pitch). Magic.

[@Ciaran55]

fucking simpleton

[@noahw5887]

DarkDrift0r Judging by your favorites you're quite the nerd.

[@RossMannell]

Seeing the sine and complex wave patterns as the strings are plucked, although not the actual way they vibrate, is an amazing angle on guitar playing. Great little science lesson for children to see as well.

[@stubb1qaz]

Yes, the video would have to be at 40 000 fps to accurately represent the sound up to 20 kHz (roughly the upper boundary of what we hear). I do not think we have cameras able to capture more than 200 fps unless they were made for some ballistic analysis so there is a long way to go. This video shows some alias of the wave that does not represent the actual vibration.

[@colemyers3231]

Would be cool to revisit now that 240 fps is commonplace and 1 million fps is attainable

[@bob-vf8mw]

@@colemyers3231 imagine what the camera capabilities will be in 9 more years

[@bradbond21videos]

I smell the world's greatest acoustic guitar music video coming. Panning through the streets of San Francisco, walking a rooftop in New York, staring into Niagara Falls, all with those awesome oscillations as an overlay.

[@jacknetarchive]

Looks like sound waves!

[@capitalex5422]

That is awesome. You can see the shape of the wave that makes the sound.

[@Axarch]

Wibbly Wobbly Timey Wimby Camera Stuff

[@AcoskyFilms]

Wimby? It's supposed to be wimey. Darn auto-correct.

[@Shaunrichards97]

Lmao 😂

[@audiojack5641]

Omg yes

[@ole1925]

Might that be a reference? To a BBC series probably?

[@washingmachine1198]

Oh hello doctor, didn't see you there

[@bamagatrmo]

Gorgeous! I have to say, it reminds me of how early cameras captured wagon wheels in such a way that they appeared to rotate backwards slowly. It's due to the frame rate as relative to the actual vibration frequency. Fascinating, scientific, a beautiful! Extra factoid: each note, one octave higher, has twice the frequency. One octave, therefore, is half the frequency. The most common reference is A440. The A above middle C has that vibration speed. This is a fantastic video!\

[@TiphanHunter]

Thats awesome.

[@liquidjorge]

If you have an old monitor (the ones that make a lot of static electricity in the screen when you turn them on) you just place the guitar between the monitor and your eyes and pluck the string. each semitone has a very different movement. If you play D you can see waves running one way and when you play D# youll see it going the other way, some notes will give waves that seem to be going slow-mo and smooth, others look very unstable, its fun

[@chamixone]

Nice guitar skills man!

[@nachfullbarertrank5230]

Should grow some longer nails, though :P

[@electricalien]

Yes. It's actually quite easy to reproduce a single note on an osciliscope. The camera's effect captures the wave forms and an osciliscope can be used as wave form generator. An oscilscope has a screen to show what the waveform that your generating looks like so its just a matter of some knob turning to get the pictures to match up.

[@Signalement]

For some reason I just love the "MMMM?!" in the beginnning!

[@JuveryaWasiq]

Lol

[@TheMasonX23]

Really cool example of the rolling shutter, and I'm so glad you played some Clapton. Great performance of Signe, such a beautiful piece :)

[@coreymath2021]

I studied all about this in physics: Oscillations, SHM, Sinusoidal waves, Standing waves, waves on a string, string instruments, transverse waves, periodic waves,resonance.. There is so much physics here in this video. Sadly, i bet only 1% of the people who see this video have taken university calculus physics.

[@PolDela]

Its interesting to solve the differential equation of vibrating string and see whether your solution "fits" the video.

[@theobromaKKO]

Idk I learned all this in high school o.O

[@tostare]

Why are you sad that people watching this haven't done a physics degree?

[@cyruswong-weissman8741]

Calculus and physics education is useful for understanding the details, but you don't need either to understand the concept of an alias frequency! Video peeps will understand it no prob, and experienced string players will get the standing wave part of it without any knowledge of calculus.

[@6SoulHunter9]

It's no so hard, I have only taken 2 physics course and I have seen it. And I don't think these are so complicated concepts. They're complicated if you want to do the math with them and compute them, but to appreatiate them a smaller intuition is enough.

[@acerockman3520]

The rolling shutter effect is amazing

[@MrPooperlooper]

00:53, I want to learn how to do that

[@Dtreen2]

one of the best signe cover's i've heard

[@makotosmobile]

what is the song name that you played from 0'57(for about 30 sec)? it's very nice.

[@ihaveliterallynoname]

Signe Eric Clapton

[@cwongman]

Its actually the alias frequency from the sample rate of the video capture interacting with the higher harmonics of the strings. You can actually calculate the video frame rate by looking at the waveforms and knowing the frequency of the notes played. You can see the same thing if you hold the guitar strings in front of a tv. It is also the same concept that makes car wheels or helicopter rotors appear to change speed or rotate backward when viewed on tv.

[@justkylevids]

@iisan1 I accidentally pasted that section twice when I was editing. If I had known this would explode all over the internet I would have been more careful heh

[@splinter1817]

@Elliot Gooding true lol

[@henrynwosu6277]

Thank you. I love you. I never knew guitar strings vibrated Like that. One step closer to understanding sound waves .

[@AGVersace100]

the G string is a little flat XD

[@gabebuchanan]

Realistically a sine wave (viewed on an oscilloscope, for example) is simply a set of points captured over a time period, and if you capture it faster or slowly it will alter in its 'accuracy'. In addition, this is a view of the actual wave being generated by the string, however it is not necessarily the same audible waveform that would be present if you were to translate the audio pressure into an electromagnetic signal.

[@sydshrooms]

I remember being a smol bean and watching this thinking it was real.

[@freindlessversion2.021]

It is real, this effect can only be seen from the rolling shutter effect which is a problem that a lot of cameras have.

[@wonderbread239]

Nope, sound vibrations aren't real. Totally photoshopped. Fake news.

[@mai-ty8fx]

Zeeker it's real tho

[@animesis]

This video is the best of Signe, not only the great imagery (the stroboscopic effect) but also the fact its inside the guitar it picked up loud and clear, the others on youtube tend to be poor quality audibly :( Great Vid! thanks for posting ^^

[@Tehnodinaroid]

who is here from vsauce?

[@reverendbuddy]

@TrialVersion8 "Rolling shutter (also known as line scan) is a method of image acquisition in which each frame is recorded not from a snapshot of a single point in time, but rather by scanning across the frame either vertically or horizontally."

[@rich1051414]

Cameras with no physical shutter have something called a 'rolling shutter' and it causes weird wavy artifacts like this.

[@windwardpro]

What else does it cause artifacts on, for comparison?

[@rich1051414]

windwardpro Anything that moves too fast for it to capture properly. One example are propellers. It causes them to look completely detached. On the other post you commented on, I went into further detail why the waveform looks so good with the rolling shutter. Its because the camera itself is being vibrated by being inside the guitar. That makes the strings appear to move more than they actually are.

[@windwardpro]

OK- that makes sense, because, yeah, I'm realizing the wavelength for these notes, especially the low strings, is WAY bigger (longer).

[@rich1051414]

windwardpro Well, they are longer cause the wavelength is longer, they are wider because low frequencies travel more efficiently than high, so it has a greater vibrational effect on the body :) That is why you can hear cars with a lot of bass from a mile away. I find the high string even more interesting, with the weird wavelength it shows.

[@AfranioSMoraes]

This cool trick is actually useful for setup, it lets you estimate the amplitude of string vibration, which influences the minimum string height to avoid fretting.

[@sznctrl]

How did you get the phone back out?

[@RowynOfficial]

Joseph D it’s easy, just think.

[@vitruongoffical1270]

Use your headphone

[@ghostie5168]

With his hands

[@d5bailey55]

you give a new meaning to "riding the wave"...i liked it...

[@IISEZIKII]

thats bullshit my iPhone doesn't do it

[@icestrawmusic998]

what iphone do you have? i doubt you have an iphone 4 wich has a rolling shutter in the camera instead of the normal type wich captures a complete exposure at the same time.

[@amadeuspaulussen]

Life is full of wonder! Absolutely awesome!

[@KevinLambguitar]

Congrats on getting ready to hit 1 million. Incredible.

[@ch33secake88]

Could watch this all day.

[@Rbrockcoble]

@cosimosalb It's the way the camera records the image. It scans from left to right, and if something is moving fast enough, it'll pick it up in multiple spots. The string really moves all together, not in waves, it's a camera trick. It wouldn't work if he turned the camera sideways though.

[@hiroshi565784327615]

Wow, this is great! I can see sine curves with the song of EC's "signe".

[@TheExquisiteRoofer]

@Kyosuke2 Yes you are correct, I was just trying to give an example to which non audio enthusiasts could understand. It is not an exact representation of the waveforms but to be able to see waveforms of that precision in a guitar string is pretty amazing to see. It is still a good learning tool to see the difference in shapes of the low frequency vs high frequency oscillations.

[@TheBlackshirtHusker]

Great song choice!!! "Tears in Heaven" made this video for me... Bravo!!!

[@ManhMedia]

Someone should give this guy an award. this is really awesome!

[@alessan]

@olliewong78 ...Actually, waves moving up and down the string are what causes the string to "oscillate up and down". They're called standing waves and it means that waves are traveling along the string in both directions, reflecting off the fixed ends to interfere constructively and destructively at fixed points. Though you're partially right, what we're seeing is a stroboscopic effect, not reality. The shape of each waveform (timbre) is accurately displayed though, and that's a big plus.

[@tomogrady1971]

You should film a series of videos where you use this technique and play songs while you take us on tours of different cities around the world. Walkting through Times Square, etc

[@TheCheesyProductions]

it is possible. you can measure the wavelength to determine frequency, then use the amplitude to determine the velocity(how loud it should be) however, as the description says, the vibrations u see may not be representative of actual vibration. but i think it is still possible with some sort of calibration

[@Ashe_Fenrir]

I felt like I was watching TV and every time I got into it somebody changed the channel... but I didn't get as mad because this is pretty cool.

[@reverendbuddy]

@TrialVersion8 yeah, i do. the definition of oscillate is "to move or swing from side to side regularly," btw.

[@cuppycakesandzombies]

BACK TO THE VIDEO. Great video dude. It just made me so...happy. And it also kind of tripped me out, but that's okay too.

[@xiondisc]

I'm pretty sure the way the recording works is by scanning the image from top to bottom. So, you might not get the same effect if it were horizontal. Unless rotating the phone also changes it's scanning as well. Also, it's probably standing up so the camera can see all the strings.

[@nelson3300]

Dude this is about to virally explode in the musician community. Look for your views to go up up and away :D

[@ClumsyWoodsman]

D string looks crazy

[@dojomojomofo]

Many, if you search for them. Basically, it's like an old TV if you know how those worked... Each frame of video is captured pixel by pixel, scanning across each line, so each pixel is from a slightly different time. If something moves by them quickly enough, it appears to distort - like these strings, or airplane propellers.

[@RisingPhoenix120]

@ElRoberto182 I believe it is caused by the fact (correct me if I'm wrong) that the iPhone captures video/images from one side to another. This video isn't implying that the string has points, but when capturing video from one side to another at a low frame rate, you can achieve an effect like this.

[@NotOlav]

i came for the oscillation and stayed for the nice guitar jamming

[@OMFGeekTV]

@ThisKid429 It's not something you turn on, it's always there. Some camera chips (CMOS chips in particular) record frames by refreshing individual scan lines, from top to bottom, rather than the whole frame at once. Video is still individual frames one after another - like a flip book. Each frame is made up of lots of lines of pixels. Rolling shutters change each horizontal line, one at a time, top to bottom, in a fraction of a second (1/29.97th of a second in an iPhone, I believe).

[@picsmics4]

@stfuerik congrats for being the first one of the kind!

[@tickeroo]

I've noticed for years that you get a similar (though less pronounced) effect if you simply look at a vibrating string with a television screen behind it. I would see this all the time if I was just laying around on the couch playing guitar.

[@pat112998]

The strings how they vibrate is so cool

[@zggame]

Very neat! It is creative to make something nice out of an error/problem.

[@kytis13]

this is way too cool! and on top of that, great music to accompany!

[@iancumberpatch6471]

No. It's an effect called aliasing, which is when the framerate of a camera syncs up with the high movement of something else, which, in this case, are the guitar strings.

[@drijfkip1]

Very cool! You could tune a string exactly to a mutitude of the framerate so that it looks like it's standing still. Would be nice see the waveform.

[@MichaelELambert]

Eric Clapton! Tears In Heaven! I know that song anywhere! Nice strumming!

[@The_Ballo]

@RisingPhoenix120 Yes, the iPhone has a CMOS camera (like a DLSR) which scans each frame one line at a time

[@bradbond21videos]

There are waveform editor VSTs out there that you can use with FL Studio or other DAWs that let you draw and manipulate waveforms, but doing it from an image would be much more difficult.

[@asad129]

FYI -- this effect is not due to rolling shutter. It's due simply to the frame rate of the camera and the frequency of the strings causing time-domain aliasing. You would see the same thing with a CCD-based videocamera, or even a film videocamera. It's the exact same effect that causes car wheels to look like they're stationary or running backwards at certain speeds on video/film.

[@NicolajTopp]

It is not the frame rate that changes with the amount of light but the shutter speed. The more light falls onto the sensor, the higher is the shutter speed and the motion of the string is captured in a very short time period. Otherwise it would be too long and the movement is blurry...

[@think2086]

As mentioned, the actually apparent waveforms are not technically what the real waves look like, because, the rolling shutter itself has its own frequency and phase, and that is interacting with the waveforms being captured. This is why the strings sometimes look radically different when he plays the same notes. At different points in time, the phase of the shutter is different, so you get random (and very cool looking) complex waveforms as a result. It's similar to the Heisenberg Uncertainty Principle, in that, yet again, the OBSERVATION of a phenomenon itself INTERFERES with the actual data observed, (even if not changing the physical strings' vibrations in this case).

[@animesis]

Signe is one of those songs that just makes me really appreciate being human

[@PIBM]

@cynthiaclaire You could try using a very fast flash running once every 1/FPS seconds: you would notice that only a small part of the image is visible in that case, rather than the whole thing. The iphones use a 'rolling shutter' technique, which record only a small part of the image at a time (scanning the view, if you will). You can have very interesting effect if the view is changing between the lines scan as seen here. Learn more on wikipedia by searching for "Rolling shutter"

[@Dread_Naught_But_The_Dark]

that is true, however, in circuitry distortion (namely in guitar amps), when a signal becomes distorted, harmonic frequencies are highly emphasized. so if you were to take said information, even with just the most basic bass frequencies, and find a way to simulate distortion (i would opt for something much like vacuum tube distortion) the output signal would seem more akin to a natural note, and could be easily synthesized.

[@PatrickLeon]

I demand a high definition / widescreen version of this!!

[@morshali]

Very cool use of physics!

[@Mormodes]

I would love to see an artist make a music video with this, changing the scenery around to keep it more interesting.

[@BenBensen5151]

Quite interesting visually whether or not the vibes represent or not!

[@poopjackable]

why exactly would anyone take the time to dislike this video. They would be all like "yes, I dislike this cool phenomenon enough to spread my negative vibes". Like wtf.

[@asad129]

It's true that rolling shutter could be an effect, though. The best test to differentiate the two would be to do the same video at the same framerate with a CCD-sensor camera, which has no rolling shutter effect.

[@TheMujestyc12]

I see an official music video coming here soon, with this

[@precision165]

Thanks for posting. Thoroughly enjoyed this. What a cool idea.

[@Las3rGirl]

I love noodling on guitar! and this is a cool camera trick too! :)

[@ErikEspangberg]

This is really cool! Looks like the strings feel, even if there's no science to it.

[@DaniloOliveira87]

a lot of information would be lost, the sound of a string is composed by an infinite number of waves superposed. low frequency waves could be seen in the image, and knowing the constructive properties and length of the string and also the tension applied to it you could know its frequency. but high frequency waves are not visible on the image. so it wouldn't be the exact sound.

[@DalltonSantos]

great idea - Dallton Santos

[@offbeatsquirrel]

Very cool video and beautiful songs. (I really like the one you played at around 1:00)

[@iisan1]

this is good... seems like you like tears in heaven so much that you played it over and over again haha

[@fireant202]

Turn this into a music video now! What a concept!

[@thenintendiacs553]

paul mccartney did

[@BrandonSorianoMusic]

Wow, this guy must really like "Eric Clapton - Unplugged". Great playing

[@TwitterInMyYahoo]

yet another win for StumbleUpon!

[@lakostal]

Vibrating strings make so beautiful sounds ;')

[@cwongman]

very nice! very true as well. This is a subset of the alias effect that I described above, but you nailed it right on the head.

[@RingOfRae]

Great discovery ! Ok, this is how ti may work : the iphone is inside the guitar, therefore it picks up at the same time, that is almost in perfect synchronicity, the IMAGE (motion picture) of the strings as well as the VIBRATION of the wooden body of the guitar. If you take also in account that the iphone (just as the ipod touch and the ipad) have a mouvement detection system, there you have it : image caption+camera (iphone) receiving simulteneously the vibrations+mouvement detection...

[@dbpettibone]

It's called Signe by Eric Clapton. It's on the unplugged album.

[@ImNotBlueBro]

This is actually math / physics combined. Its waves. Which consists of both. So both of you are correct.