Image Recognition and Python Part 2

Key Takeaways

hello and welcome to part two of our image recognition and image manipulation tutorial Series where we left off we were basically just downloading everything that we needed and now we're ready to start programming if you don't know how to get to this window uh so like if this is really your introduction to even python uh once you've downloaded and installed python if you go to your start bar and search for I d as in dog l e uh you should find idle and then in parentheses python GUI or guey click on that and that should bring up this window here and you could program in here but I I don't prefer it so you can go file new window and that'll bring up an empty window and then you can subsequently close out of this window then you should have something called like Untitled right so it's like an Untitled text document you can type stuff in here and it's cool subsequently the next thing you'll want to do is you want to file save as you'll save it in the same directory I'm going to close out of this cuz I don't need this but you'll save it in the same directory as that image folder so if I was to save this one which is what we'll be coding in um it brings up in here and so I've got the image file folder here that you could extract from tutorial images so if you double click to this what's in here is that numbers file and all that I'll go back make sure you save uh this video like the program that we're going to be typing in save that file right here in the same directory as IM images and when you do save the file make sure at the end of the file you put py otherwise it just saves it as a regular file and it's kind of annoying so anyway once you've done that you should be here at this empty screen and you're ready to go so the first thing that we need to do is bring in all the other uh Imports that we are going to be working with so basically the stuff that we downloaded if you didn't already have it so like I said in the previous video if you're operating on a 32bit version of python then you will you will do this you will import Capital IM M AG G now I'm on 64bit and I'm not using pil so we're just going to leave that out but it I'll just comment this if you are on 32bit OS then you will do that otherwise if you're going to be working with us with the same things that we've used you're going to do from pis which actually is from pillow not python Imaging Library import capital i m a g e so besides this change right here in in the first line of our script nothing else will be different from what we code so uh no matter what you're using you should be able to follow along no problem so next thing we want is to import numpy so we're going to do import numpy as NP now that way when we call numpy we can just type NP instead of full numpy cuz we're lazy now let's talk about how to work with an image so if we bring up um in our directory you can double click on images and that should look like this so what I'd like to do is let's just open up a simple very simple image and we'll open up this dot image so let me just bring that up it is you probably can't even see it in the video but it's a really I'll just zoom in it's just a dot in the corner all right so uh that's the image that we're going to look at real quick just for basic uh reasons so we'll say I for shorthand image equals capital i m a. openen and then you're going to want to specify the path to that image so if you put this uh script in the same directory as that images folder all you'll have to do is images.png but if you put it somewhere else you'll need to give the full path um or you could do like some tricks with this stuff but uh if you if you're not comfortable you should just make sure the script is in the same directory and if it says it can't find it then either you've made a typo or just try to give the exact full file path next uh we're going to say I a and what i a r is standing for is just we're just making it up it's a variable but I a in my mind is image right for the I and then AR will be the array and then that's going to equal np. asarray and then what do we want to convert to an array or an NPI array rather we're going to use I right so what this is going to do is going to spit out an array that corresponds to our image and the image array is going to come out as a threedimensional threedimensional array so this means there's an array within an array within an array or if you use a list it would be a list within a list within a list depending on how we're reading it in Python that's what it's going to it's going to be different things right and that entire list you know so the outside Dimension is the whole image the second dimension in is going to correspond to each row and the third dimension in corresponds to each pixel in that row and the items within that list of the pixel is your red green blue or RGB and then you've got Alpha and that's for each pixel so let's go ahead and and look at an example since that might sound really confusing so we're going to print out I and just print it uh to the console now you'll just need to make sure you go file save or you can do contrl s and then to run the script you either hit uh run and then run module or you can hit F5 so that should bring it up and it will print out this array here so as we can see uh we've got let me see I I can't really scroll this out but uh on yours you should see you know like a box of numbers right and then another box and another box and all the boxes pretty much should be 255 within them except for the first one it's got a z0 0 and a 255 so this entire uh array right right that is let me just fit everything into this window that is the image right now each one of these arrays here actually let me get it right like this uh each one of these and actually it's more like this anyway uh each one of these right uh is the row within the image and our image is an 8 by8 so let me go ahead and bring that image back up again let's edit it so it comes up in paint and I'll just drag it over and zoom in so as you can see you know there's 1 2 3 4 5 6 7 8 by 1 2 3 4 5 6 7 8 you'll have to take my word for it or you can look at it but uh anyway yeah if we went to resize right 8 by8 anyway so that's our image and so we have eight of these rows 1 2 3 4 five 6 7 and eight and then also within that row we've got our pixels and like this is a pixel in that row this is another pixel and we since it's an 8 by8 we're going to have eight pixels right so you can almost see is like the pixel is like part of the column and then this entire list of pixels is a row so anyway that's just some Basics we'll get into more detail in the next video if you're having any trouble up to this point feel free to use the comment box uh most of the comments go to my email and I do respond to the comments so if you're having any problems just feel free to uh post your question or your problem and I'll do my best to help you out anyway as as always thanks for watching thanks for the support and subscriptions and until next time