Working With Images in Julia | Week 1, lecture 3 | 18.S191 MIT Fall 2020 | Grant Sanderson

The basics of manipulating and viewing image data with Julia.

Contents
00:00 Introduction
00:15 Pluto notebook
00:35 Pluto: Using a webcam as input
01:12 What is an image?
01:31 Zooming into an image gives pixels
01:50 Indexing into an image
02:10 Julia: Strings
02:20 Julia: Download function
02:30 Julia: "using" and Images library
02:47 Pluto: begin..end for multiple lines
03:00 Pluto: Images are displayed as images
03:05 Philip the Corgi appears for the first time
03:20 Julia: typeof function
03:39 Julia: 2D array
03:50 Julia: RGB type for colors
04:45 Julia: size function (dimensions of an array)
05:10 Julia: Indexing into an array
05:52 Julia: Slicing an array
06:42 Julia: Integer division
07:42 Julia: Concatenating arrays and images
08:25 Julia: reverse function
09:19 Manipulating pixel data
09:36 Julia: Copy function
10:04 Julia: for loop
10:37 Julia: for loops return nothing
11:37 Julia: Broadcasting with "."
12:35 Julia: Accessing a field with "."
14:25 Transforming an image: Decimation
15:07 Preview of image blurring
16:40 Pluto: Interactive slider from PlutoUI
17:30 What does blurring do?
17:56 Preview of edge detection

[HungNguyen-lzxb]

Grant Sanderson and Julia? Am I dreaming? Is this real?

[Visualization]

It's really amazing to see Grant here!

[OlliWilkman]

Wow, familiar voice. Didn't know Grant was a Julia coder too :)

[ykr]

Whoever from the Julia team thought of bringing Grant for this is a genius

[subhasish-m]

Grant? Julia? Pluto? Image Processing? How much better can one video get!

[tonyctan]

Mass switch to Julia after Grant's endorsement today.

Hello to former R users 🙋‍♂️

[PanzerfaustBR]

3blue1brown + Julia + Pluto? All my bromances in one video

[buivietdung]

Grant and Julia in one video? 2020 isn't so bad after all

[niconeuman]

This is a great resource! Julia is a great language and it needs courses like this to become more widespread

[samm]

Is the one speaking the one from 3blue1brown?

[hhhults]

sheesh. this looks so sexy compared to mathematica. especially the bind part

[uttiyamaji]

I was doing well with R and Python but now I'll start Julia as Grant is teaching it

[abhishekswain]

Very excited about this course! Just what I wanted! 😍😍

[wpw]

I, for one, am happy to welcome our new 1-indexing overlords!

[petergoodall]

convolve and blur2 not defined in notebook for lesson 1.1 of Spring 2021 Computational Thinking . Would be nice if environment was compatible with demo. Its important that environments for beginners are error-free. Their problem-solving experience in the environment is limited.
Could find no reference to convolve when searching `julia convolve()` or similar.
I am assuming the video is re-used from another context (2020) that had blur*() and convolve()

[TheAIEpiphany]

Cool stuff:
* A webcam in Pluto notebook!? Very elegant.
* Binding widgets to variables (somewhat like Streamlit)? Awesome.
* Grant? Much wow.

Meh stuff:
* why oh why did Julia have to use the "begin" and "end" boilerplate code? Like really it's impossible to infer that info otherwise? Python is crying right now.

[MaddiHD]

Thought it was Conan O’ Brien at first glance and I’m still not over the confusion

[acsap]

I hardly comment anything, anywhere but this, is just great :D Thank you!

[meta_cog]

"oh wow, this guy looks strangely similar to the one from 3B1B, surely this can't be the same person"

Then I continued listening...

[MCRuCr]

Its great to see the creator of 3Blue1Brown so invested into the Julia language. Julia is truly a big step in the right direction