11.6: Computer Vision: Motion Detection - Processing Tutorial

In this computer vision tutorial, I show how to analyze the pixels of a video to detect motion. This technique is also known as frame differencing.
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Links discussed in this video:
Computer Vision for Artists and Designers Essay by Golan Levin: www.flong.com/t...
Image Processing in Computer Vision: openframeworks....
Source Code for the Video Lessons: github.com/Cod...
p5.js: p5js.org/
Processing: processing.org
For More Computer Vision videos: • Computer Vision
For More Coding Challenges: • Coding Challenges
Help us caption & translate this video!
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📄 Code of Conduct: github.com/Cod...

[@paladin1147]

I thought I would really choke on this one because it seemed hard for me to comprehend but after checking the video twice and really focusing in, I got it. You really did such an amazing job on this one. I really appreciate what you do .Even after 2 years your learning people. Seriously! Best teacher man!!!

[@bomggotge305]

This is a best lesson I've ever seen.

[@TheCodingTrain]

I'm so glad to hear!

[@philipbraatz1948]

4:41 This whole time I thought you were just a floating torso until today

[@ArthurPierrot]

So funny when you dance :D I understand why no people disliked that video, it's soooo cool !! Great Job !

[@beladn710]

LOL the funniest programming course ever, it proves that the line between genius and madness is very narrow

[@ayitsalex2893]

Dude coders are allowed to have fun, our brains would catch on fire if we couldn't have a laugh while working :D

[@martinboom01]

Hey man, you ruin my imaginations of adobe programmers skills :D It seems to me that adobe master collection should be done in a week !!

[@lucianomartinez85]

hello, since I met your channel (6 hours ago) I'm learning twice in college! I can not stop watching and wanting to know more. how do you explain is understandable, although I do not speak your language (I'm writing this on google translator). I have a question for you: manages to capture the moviento of a beam of light with background subtraction. but I need to replace the entire motion detected by figures (ellipses) to emulate the movement of light (infrared light) in a more visually appealing way. the violet ellipse ellipse (lerpX, lerpY, 36, 36); It is a single figure, following a movement. as I can make every pixel in moviento be replaced by hundreds of ellipses? Thank you!!

[@lucianomartinez85]

hello ! im from argetina , im a student in multimedial arts , where are you from?

[@ShokoCC]

Same here, I'm from Peru tho

[@kikizhu1358]

Hey just wondering if there is a source code for this series. Coding train on GitHub only has 1-9 : (

[@audreyli836]

Thank you for bringing so much fun to the lessons!

[@twistedsim]

9:28 best.moment.ever

[@theodoremichels756]

As always, thank you so much for creating such helpful content. I was trying to find the code from this lesson on GitHub, but didn't see it - does it exist anywhere else? Thanks in advance!

[@tobiasmortier5102]

I tripple hit the like button when you started dancing xD keep it up

[@naraendrareddy273]

Now I have a question. We have detected the objects. But how do we calculate the velocity of the objects if we want to?

[@bazaci]

All these videos are so helpful and fun. Thanks .

[@bryphi77]

I finally have something of value to comment... yay!!! This works better if the loop is placed in the capture/movie event. Dan... You are the emperor of teaching. This series in particular has been so helpful to me. I have tried to implement a nearest point algorithm in the past and failed, but I was easily able to fallow along and actually learn and understand well the process. Thanks so so so so so much... again!!!!!!!!!!!

[@TheCodingTrain]

so glad to hear, thank you!

[@nagarjunareddipaku678]

Hey at 11.12 sec there you have done betterjob. So I a have an idea about, can you make a program for that exactly 3d virtual frame( fix your face then when you giving input as your face to webcam when it matches to your frame as you did at 11.12, then only it has to take the image ) so can you do that. Or tell me where I can get that exactly. Please. Thank you

[@MilanKarakas]

It will be very useful with addition of servo motors as an automated camera tracking. Thanks.

[@TheCodingTrain]

+WildMania great idea!

[@faces_of_places]

your lessons are just genius! thanks a 1000 times!

[@prateekpriyaranjanpradhan3963]

Sir , can we use this software and codes to interface other hardware devices? like taking the data output to give input to other devide?

[@robertobrenes5283]

Yes you can, there is a serial interface in processing as far as I know but I bet there are like 10 different ways to do that

[@leamucho]

Thank you Daniel!!! and also for the book!!! :D

[@alessiaganzerla335]

ArrayIndexOutOfBoundsException: Index 3 out of bounds for length 1 this is what appears even if I copy and paste the code

[@rodrigovasconcelos1660]

I'm also having this trouble

[@vvzen]

Great video, as always! Somebody knows a good webcam for macOS that can turn off auto white balance/exposure? Any tips or amazon links? I'd like to buy one for some experimentation with OpenCV. Thanks!

[@TheCodingTrain]

Would love to know myself!

[@i.i]

I want to do this with p5.js :

[@operationskate7]

I tried to replicate this in python with OpenCV but the double for loop calculation seemed to be taking way too long and made the stream look like a slide show. Any suggestions?

[@operationskate7]

I tried using threads as well but that gave weird results.

[@louen8413]

Kind of late for a reply... but might be useful for someone else. I'm gonna guess, either you need a faster computer (not much you can do there except getting one), or a camera with a lower resolution, perhaps you're capturing video in FullHD or so, which makes the "for" loop waaaay slower. In his use case, with 640x480, it means the loop is iterating 307.200 times per frame, now, with FullHD (1920x1080) that would be 2.073.600 times, that's almost 7 times more interations, therefore, 7x slower.

[@reactorscience]

Amazing tutorials, you make learning all this super easy and your dance is awesome too.

[@TheCodingTrain]

Thank you!

[@TheLukinho94]

It is possible to move the function of the threhsold in a class and then recall it when a key is pressed?

[@arhamcodes]

Why it shows Null Pointer Exception when I try to copy video capture to previous image after video.read() method ?

[@selvapriya4115]

i try to track white pixel in a image, when the pixel moves,it merge with non moving white pixels.. how can i seperate moving and non moving pixel in a image using opencv c++

[@AdrienSales]

As walays, great session. ANy hint on how to process a Youtbe live stream and perform that kind of stuff ? I saw your demo on P5.js, but not for processing. Thank you again.

[@Chris-hr8lt]

hey i cant find the source code in the repository

[@prajwalwaingankar3636]

@@hsbrathen1 sketch motion detection right?

[@daviddg182]

Where do I find the p5.js version of this?

[@guruteja7151]

Is there a way to find out if a user is talking with in a image frames of video, I mean with out audio??

[@Ejotei]

can someome help me please?! I need to make a processing file that increases the volume of a track by detecting motion from a webcam, I'm very new to all of this and managed to get the webcam and track working however I have no clue on how to get it to change volume based on motion.

[@sarahkatecre8]

Okay so.... all is fine and dandy except the rectangle that draws the black and white motion detection is stretched thin across the top of my canvas, and my webcam is a small square underneath - neither of which take up the entire canvas and the ellipse just stays in the center of the webcam drawing.... I assume this is due to the dimensions? Can't find what to change tho? Please help :(

[@sarahkatecre8]

Update.... Checked original source code used, to see if I just made an error myself and it still came up... "video = new Capture(this, cameras[3]);" (line 24 of source code given in link in description....) Changed [3] to [1] and it seemed to solve it for me... Leaving this up for anyone who comes across this in the future - let me know if it helps :o p.s. in case you couldn't tell, I don't have much experience in this... but that's why I watch these videos XD

[@TheCodingTrain]

Glad you figured it out! You can try this: printArray(Capture.list()); This will show you all the various camera options/resolutions that are possible!

[@sarahkatecre8]

The Coding Train Thanks so much ☺

[@tommyvanini9019]

Hello to everyone. Dan, your videos are absolutely amazing! Thanks you for all the wonderful things that you teach us! I have a question, if someone is so kind to answer it. I tried to change the dimension of the window, but it seems to work only with 640x360, even if I changed the dimensions of the PImage too. The strange thing is that I tried to hard code the dimensions to 1280x720 and, even if my webcam can give me those resolutions: [0] "name=HP Truevision Full HD,size=640x480,fps=30" [1] "name=HP Truevision Full HD,size=176x144,fps=30" [2] "name=HP Truevision Full HD,size=320x240,fps=30" [3] "name=HP Truevision Full HD,size=352x288,fps=30" [4] "name=HP Truevision Full HD,size=640x360,fps=30" [5] "name=HP Truevision Full HD,size=1280x720,fps=10" [6] "name=HP Truevision Full HD,size=1920x1080,fps=5" [7] "name=HP Truevision Full HD,size=640x480,fps=30" [8] "name=HP Truevision Full HD,size=176x144,fps=30" [9] "name=HP Truevision Full HD,size=320x240,fps=30" [10] "name=HP Truevision Full HD,size=352x288,fps=30" [11] "name=HP Truevision Full HD,size=640x360,fps=30" [12] "name=HP Truevision Full HD,size=1280x720,fps=30" [13] "name=HP Truevision Full HD,size=1920x1080,fps=30" it works only with [4] and at size(640, 360), not other sizes. I think that the problem is in the nested for loop because sometimes it gives me the Array out of bound error. Does someone know how to fix this problem? If you do, I'd be very pleased to hear your solution. Again thank you Dan for your work!

[@TheCodingTrain]

Would you mind asking at discourse.processing.org/! It's a better platform for Processing and p5.js related code questions. You can share code there easily! Feel free to link from here to your post.

[@giacomoandrigo462]

Hi! I have a problem to solve. I would like that once a pixel become (let's say) black thanks to the motion, it stays black forever. The aim is to draw the path of a moving object. Any hint?

[@danthemancasey]

HINT? Create waspixelblack[loc] to store if each pixel was black, place in if statement... if threshold && waspixelblack == false. Anything more would surpass "hint".

[@vilhovainio132]

Or you don't have background in draw

[@DogwafflDan]

How about a video on gradient space compositing?

[@cap-advaith]

Nice

[@mallikebadat7337]

Sir, which language is good for computer vision?

[@peterha2204]

Never sorry to watch your videos!

[@NansEverything]

could it be used with movie file like mp4 or mov??

[@sarthakkumar150]

Loved the dance

[@SuperRandomdud]

Is there a way of making this program locate multiple people at a time, about 20?

[@TheCodingTrain]

take a look at the more recent blob detection videos.

[@peterhayman1789]

awesome! thisd be neat to use javas robot class to move the mouse! im hopin to use it to look around in skyrim :-)

[@user-kz2xi4ef3r]

best lesson....

[@Avriox]

How do you always "cool" algorithms to recreate in code?

[@TheCodingTrain]

Suggestions from others!

[@TidalMaker]

"I am a magic pink dot manipulator."

[@user-ui2qk6jg5n]

where can i find this code? did u upload it anywhere? thanks

[@TheCodingTrain]

I need to work on organizing this better but here you go! github.com/CodingTrain/website/tree/master/Tutorials/Processing/11_video

[@geoffwagner4935]

Good t-shirts are the ones that need no explanation by the wearer

[@thanapongpanichob4500]

9.20 WTF!!! what the funnyyy hahahahah:DDDD

[@shoaibmirza3082]

nice !

[@furrane]

As always :)

[@borjonx]

MOTION DANCE DETECTOR!!!! mmChuh mmChuh mmChuh mmChuh mmChuh mmChuh mmChuh mmChuh --TheMagicPinkDotManipulator circa 2016

[@dsorangerpvpandpve]

17:07

[@prashanthkumar0]

awesome dance 😂

[@AWANIT22]

if u r sending. send me separate code for each.

[@JGunlimited]

Links to code are in the video description.

[@dndamian]

dude! coders don't dance!

[@TheCodingTrain]

This coder does :) - The Coding Train Team

[@dndamian]

The Coding Train love your tutorials! Thank you for sharing the knowledge!!! Greetings from the galapagos islands

[@dheepakgobinath4346]

Paithiyam