OpenCV Python Tutorial #7 - Template Matching (Object Detection)

Welcome to another OpenCV tutorial! We'll be talking about template matching (object detection). In this video, we'll use an image of a soccer practice and use OpenCV to detect the soccer ball and find it's exact location. For example, the image of the ball will be our template, and we'll use OpenCV to match it.
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📄 Relevant Documentation: opencv-python-tutroals.readth...
📝 Code For This Series: github.com/techwithtim/OpenCV...
🔍 Playlist: • OpenCV Python Tutorials
⭐️ Timestamps ⭐️
00:00 | Setup & Images
02:35 | Loading Template & Base Images
04:55 | Template Matching Methods
07:00 | Theory Behind Template Matching
14:10 | Displaying Matches
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⭐️ Tags ⭐️
- Object detection in OpenCV
- Template matching OpenCV
- Python
- Computer vision
- Cameras and video capture
⭐️ Hashtags ⭐️
#OpenCV #Python #TemplateMatching

[@ananthramvijayaraj4554]

Tim you don't need to apologize for the lengthy explanation, that's the whole reason why we are here.

[@CommonKnowledge42]

This statement right here! I wish I could like your comment at least 19 times.

[@bluidguy4007]

I wholeheartedly agree, there are a few people I watch their videos like this for, and that's why, you do a great job at explaining things, keep up the good work!

[@ACodingWoof]

Yup!

[@joseph13313]

You're so right. Sometimes im looking to a tutorial and i need to understand this code's logic to learn perfectly. Tim is doing it so good!

[@darwinkusuma6757]

i agree, don't need to be sorry for the long explanation, i really thankful you explain it on detail

[@CryptoDabber710]

Tim you do an amazing job no need to apologize for the lengthy explanations they are actually extremely useful. I'll usually watch your videos multiple times just so I know I'm getting the information.

[@Atharva_Vashist]

I was interested in coding and chose python as my language to start, and you helped me to clear my basics, and explore many modules like opencv , kivy etc. You explain very well. Thank you for your videos. You are the best youtuber teaching python. Keep it up!!!!!!!

[@DL-yu8jg]

Gotta say, this is one of the most well explained Python-related lectures I've ever witnessed. Thank you so much for the video. Really helped me A LOT.

[@Traxirage]

Great tutorial! For future reference, if you want to select a segment of two lines, you can hold Shift + Alt and drag the mouse. This way it won't select all the way to the end of row, but only to the column you move your cursor to.

[@raviolismudge]

FOR THE LOVE OF GOD, I SPENT MY WHOLE DAY ON THIS T-T Thank you so much. I am crying tears of joy. My professor refuse to help us with anything that have to do with programming, he only talk about the math behind visualization. Thank you so much.

[@73Ferret]

Thanks for this series Tim. You have a very nice style of presenting and explaining how the code works.

[@jaakkaan4784]

AMAZING VIDEO THANK YOU for the thoroughness. Absolutely covered all areas where confusion or curiosity could come up!

[@nicolasa.bermellferrer8025]

Your explanation was actually pretty good. Thank you!!

[@mehmetsezgin2308]

Tim that is pretty straightforward tutorial. Thanks !

[@alexandrevalente9994]

Great example to illustrate the use of the convolution here.

[@phamminhhung3219]

Actually your long explanation is useful for us, it illuminates us how things work and you should keep doing that, or maybe you can implement some drawings

[@sunwukong6268]

Your "lengthy" explanation was great. Not as long as you might think and comprehensable.

[@tsraikage]

how sad I've never found your channel before. i would be step or two higher than i am right now. your explanation methods are outstanding. great job

[@endab5517]

You are gifted. Thank you for the content.

[@ajarivas72]

He rocks

[@natomxavi]

Grrat explanation bro, thank you so much

[@hackercop]

Glitch at 12:20 that he forgot to edit out lol. Great video, am trying to learn object recognition.

[@TeckWill]

Great job with your tutorial videos Tim! I understand that with the methods you shown we can find the exact same pixels pattern in the image. Now, I wonder, for example, how could we find all the shoes on the image from the template image without them being perfectly identical. I suppose it will be necessary to go towards artificial intelligence / deep learning? I'd like to know what you would do and see a tutorial video on it.

[@RandomGuy-df1oy]

At the end of the video, you don't need to resize the image at every step. Just resize where you are showing the image at line 23 as cv2.imshow("Match", cv2.resize(img2, (0,0), fx=0.8, fy=0.8))

[@princemajestal8100]

Hi! I have two questions. First, would it be possible to do this with a webcam feed instead of an image? And second, supposing I don't want to draw a rectangle but wanted to execute some code if there is a match, what condition would I use for my if statement? Thanks a lot, great video!

[@zack8247]

Great video!

[@RasmusE]

Hi Tim, great videos about CV2. If I want to create template matching in CV2 but the template and the image are of different sizes. How do I account for that? Once in a while I get a secret message consistent of characters in different alphabets and I want a script where I can select one character and have it look through a bunch of images with all the alphabets I know and make a comparison. It could be something like the Arcadian Alphabet or Antiker code I have to match against. Any help in the right direction would be appreciated.

[@peschebichsu]

Does it also work to match similar images too (like I think it was pyautogui, where you can give it a required confidence)?

[@w-e-7963]

Great video - thanks. You might want to use the word 'assign' instead of 'is equal to' (let the math teachers have the latter one).

[@boktorinator693]

Thank you :)

[@vingo1998]

Great video! You are so cool

[@JainmiahSk]

Please do series on product recommendation system

[@smoothrain]

Love you tim

[@addohm]

Tim, what about margin of error? What if there is a different pattern ball?

[@Yurgen_S]

Tim, Id like if you could give me some tips, I'm facing a similar problem to this pattern matching thing: I have patterns, they are very simple in shape and color (triangles, squares and such), but i'm *trying to detect them in video*. And in the live feed, *unlike this one-to-one matching*, the patterns could appear bigger, smaller, maybe slightly off colored. I get that i'll be processing multiple frames as individual images, and I know there are some techniques to help me with "video variables" that may distort patterns, like applying histogram exposure equalization, noise filters, etc. What should i be looking around, in OpenCV? I'd have to classify what symbol it is, but maybe matching for each possible symbol might do it for me. What other more robust, AI-ish techniques could i apply to have more "safety" against such variables?

[@jeepjr]

Teacher, first congratulations for the channel. I need your help, I have a simple image with a range of 5 placements where the quantity is identified, how do I identify the biggest color type red and say where the X,Y is, and if you can help me, and only for create an alert.

[@cleancode9601]

Sir please upload some video on curve analysis... please sir

[@olekristianmller-hansen4220]

Hi! Can I use multiple templates of soccer balls and add up the results to better detect soccer balls?

[@alexkotov2983]

Is there a way to increase accuracy of matching? I'm trying to detect objects on my screen but it doesnt work.

[@ricard458]

In the following command I multiplied by 4 to get a bigger rectange. How can I save only the image of this rectangle ? cv.rectangle(img_rgb, pt, (pt[0] +w*4, pt[1] +h*4), (0,0,255), 2)

[@dreamwork69]

My question is so everytime we have to run 6 different windows like that or we just pick one method that work best? Thank u

[@jollokim1948]

How come i was not notified about this video. Damm you YT 🤦‍♂️

[@spook2387]

He accidentally released it instead of ep. 6 and then set it to private so you've received the notification for that time. At least that's what I understood that happened.

[@py_tok5589]

lovely quite cool TIM, THE MASTER. can you detect /extract dimensions? can you extract the diameter of the ball roughly? may be you do a tutorial extracting dimensions from images. Thank you Tim

[@chrismckinley3110]

Wouldn't the rough diameter of the ball be the width of the square cv2 draws around it?

[@alessiopierdominici4240]

Which chair are you using?

[@aimanyounis8387]

template mathcing is not convolution it's correlation, which means that you don't flip the kernel before you pass it on the whole image : another defintion of correlation is convolution withour flipping.

[@user-pn8rh7fb4q]

nice

[@alexmboutchouang8281]

hallo Tim i did not get the tutorial 5 i don't know why is it normal or did i missed something

[@vsdsas]

result = cv2.matchTemplate(img2, template, method) cv2.error: OpenCV(4.8.0) D:\a\opencv-python\opencv-python\opencv\modules\imgproc\src\templmatch.cpp:1175: error: (-215:Assertion failed) _img.size().height

[@bharathc7033]

i will run in open cv template matching and my rectangle line shoe multiple line why?

[@ShubhamTure]

image assertion failed (-215) . Even after image is being loaded properly. Any help?

[@shreyasvedpathak5579]

I tried this tutorial on another image which is from another sport involving a ball i.e. cricket, and coincidently, the third model plotted a bounding box on the player's chest. Is this the model's issue or are we misinterpreting the output for that model?

[@ajarivas72]

Perhaps you need a neural network and trained with the desired results

[@nilaier1430]

Hey, btw, how can you detect multiple different templates in the image? I'm trying to find an answer to this tricky question, but can't find it anywhere.

[@ajarivas72]

Why don’t you run the code several times ? Or loop it ?

[@pranaygundu]

hey "tech with tim youtube ":) , I just started open cv course and I am really enjoying it :). but should I need to master the math behind openCV functions ???? to be a good programmer .........whatever :) ...........

[@abdullahahmed7781]

if you just want to *use* openCV then you dont really need to understand the math. But yes good programmers are also good mathematicians, understanding maths is very important in CS.

[@pranaygundu]

@@abdullahahmed7781 thank you so much😭😎

[@WakilSahak]

❤️

[@justwatchv]

❤️❤️❤️❤️❤️

[@mohamaderfanmirkhani6202]

how can do Template Matching on video?

[@kewalshah6448]

Can someone tell me the name of software he's using for this code I am using PyCharm but it is giving me some difficulties

[@ther3negade273]

sublime text editor, but sublime by default does not have a compiler so you can use the command prompt to run the code

[@kewalshah6448]

@@ther3negade273 thanks man 👍

[@domillima]

Everything is clear other than the explanation of using TM_SQDIFF and TM_SQDIFFNORMED. What is this line doing?

[@VShopov]

thats the image recognition method that is being used

[@vrtheking]

You streamed Chess in Discord just now...

[@komalgupta2226]

You were literally fast posting videos lol

[@VictorPerez-od7zh]

Weird I didn't see tutorial #7 2 days ago or yesterday

[@ananthramvijayaraj4554]

Me too

[@mickon7404]

My opencv doesn't work :((

[@jagermeister1888]

Hey, i'm looking for collaboration into any python projects (my skill is somewhere at intermediate level ), let me know if you need help or if u just want to share your code with someone :)

[@ananthramvijayaraj4554]

Why are there only 470 views on this video or is it that my phone is glitched out

[@faneeshmunjal3308]

First!!

[@dangus5326]

DUDE Wut 1:00

[@malhardharmadhikari5831]

Ig I will never be able to do big project

[@nelsonchika]

Second

[@MegaLenrique]

muchas gracias por compartir, comprendo como funciona pero no me funciona jeje..... [WinError 2] El sistema no puede encontrar el archivo especificado [cmd: ['py', '-u', 'C:\\Users\\Luis\\Desktop\\AGROLUIS =)\\practica lll\\template matching\\OpenCV-Tutorials-main\\tutorial1.py']] [dir: C:\Users\Luis\Desktop\AGROLUIS =)\practica lll\template matching\OpenCV-Tutorials-main] [path: C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\WINDOWS\System32\OpenSSH\;C:\Users\Luis\miniconda3;C:\Users\Luis\miniconda3\Library\mingw-w64\bin;C:\Users\Luis\miniconda3\Library\usr\bin;C:\Users\Luis\miniconda3\Library\bin;C:\Users\Luis\miniconda3\Scripts;C:\miniconda;C:\miniconda\Library\mingw-w64\bin;C:\miniconda\Library\usr\bin;C:\miniconda\Library\bin;C:\miniconda\Scripts;C:\Users\Luis\AppData\Local\Microsoft\WindowsApps;C:\Users\Luis\AppData\Local\Programs\Microsoft VS Code\bin] [Finished]

[@krishnamenon5566]

First

[@rayaanibrahim4808]

4th

[@saulaxo]

no fun playing "where's waldo" afther this

[@infernozayed9559]

It's not soccer, It's Football!!

[@tcgvsocg1458]

Your really good your soft really bad

[@Eswar.]

How to completely learn one language make a roadmap please And also smile in videos Dont be like a robot

[@ananthramvijayaraj4554]

True there isn’t much humour in the vids but the quality of the content is amazing

[@Eswar.]

@@ananthramvijayaraj4554 yes i know

[@shahriarhajiabbasi830]

I HATE that shirt ....

[@Dg2020]

who cares?

[@sohannikumbh4802]

Second