1 00:00:00,730 --> 00:00:04,050 So let's get into some arithmetic operations using open. 2 00:00:04,210 --> 00:00:10,310 So what arithmetic operations are they basically adding matrices to imagery and by adding mistresses 3 00:00:10,430 --> 00:00:13,500 or subtracting matrices from or imagery. 4 00:00:13,670 --> 00:00:19,130 It has the effect of increasing brightness or decreasing brightness or intensity. 5 00:00:19,130 --> 00:00:24,080 So to do that we actually have to first create the matrix that we want to add subtract to our image 6 00:00:24,620 --> 00:00:29,000 and non-pay has actually has built in functions one called empty ones. 7 00:00:29,000 --> 00:00:35,470 This allows us to create an array which is of this dimension which is same dimensions as image here. 8 00:00:35,990 --> 00:00:42,790 And we ascended and type to unsane and to get it which is what open CBEST uses to store or image data 9 00:00:43,850 --> 00:00:46,020 and we multiply by Escuela 75. 10 00:00:46,020 --> 00:00:50,680 So if we wanted to see what this looks like let's just copy this line here. 11 00:00:51,500 --> 00:00:54,780 And run it separately in a different cell. 12 00:00:55,900 --> 00:01:00,530 And it's actually just printed here and there we go. 13 00:01:00,540 --> 00:01:08,340 So as we see these images of matrix of 75 and here of course the same dimensions as this image here. 14 00:01:08,860 --> 00:01:12,980 So using the CV to the add function it adds these two matrices here. 15 00:01:13,180 --> 00:01:20,560 Other uses function this and this image or I should say has to have to seem them actions which is why 16 00:01:20,560 --> 00:01:24,230 we follow and copied it into this one function here. 17 00:01:24,670 --> 00:01:26,950 And likewise we do it with the subtraction function here. 18 00:01:26,950 --> 00:01:29,740 So let's see how this looks when we actually run this function. 19 00:01:32,050 --> 00:01:32,590 There we go. 20 00:01:32,620 --> 00:01:35,750 This is a darkened image here substantially darker. 21 00:01:36,130 --> 00:01:38,380 And this is a and image here. 22 00:01:38,440 --> 00:01:43,330 What's important to know is that let's say we did a 175 here. 23 00:01:43,450 --> 00:01:46,540 What do you think would have happened with certainty. 24 00:01:46,930 --> 00:01:51,210 This one is even darker which means that volumes are less big. 25 00:01:51,230 --> 00:01:52,830 Bigger than 175. 26 00:01:52,960 --> 00:01:57,510 These are the only ones that show up not because everything else cost to zero which is why it's black. 27 00:01:58,030 --> 00:02:01,860 And similarly there's a lot of white points or very light coats here. 28 00:02:01,900 --> 00:02:08,590 What happens is that when you add 175 to these points it actually reaches 255 which is white as you 29 00:02:08,590 --> 00:02:12,340 can see sort of has the effect of clipping highlights in some areas here. 30 00:02:13,920 --> 00:02:17,780 Please know that we can't ever exceed 0 and 255. 31 00:02:17,960 --> 00:02:21,520 So whether we're adding when we're adding literacies to imagery. 32 00:02:21,620 --> 00:02:27,500 Keep that in mind that you will get some clipping which is what we saw in the black and white images 33 00:02:27,500 --> 00:02:32,500 here. 34 00:02:33,030 --> 00:02:38,680 So let's start doing some bitwise operations and icle and device operations and masking because that's 35 00:02:38,680 --> 00:02:42,320 essentially what you'll be using these bitwise operations for. 36 00:02:42,350 --> 00:02:46,180 They're quite handy when you have to mask images which you will see later on in this course. 37 00:02:46,420 --> 00:02:48,460 But for now we'll just enjoy this topic. 38 00:02:48,460 --> 00:02:51,880 So firstly let's create some cheaps here. 39 00:02:51,880 --> 00:02:55,580 So we're going to create a square and an ellipse here. 40 00:02:55,610 --> 00:03:00,730 Now you may be familiar with creating a rectangle or square I call it because it's seem that mentions. 41 00:03:00,740 --> 00:03:02,140 I for this one. 42 00:03:02,530 --> 00:03:04,600 However an ellipse is slightly different. 43 00:03:04,600 --> 00:03:07,750 It doesn't actually follow the same standard as a sicko. 44 00:03:07,780 --> 00:03:11,860 You can check the weapons in the documentation to get some details and one go into it in this chapter 45 00:03:11,860 --> 00:03:12,570 here. 46 00:03:12,640 --> 00:03:14,090 It's taken too much time. 47 00:03:14,520 --> 00:03:18,510 Let's just run this function and we see it here. 48 00:03:18,560 --> 00:03:24,640 So elipse are single efforts and has actually not a full of study parameters to create sort of a semi 49 00:03:24,640 --> 00:03:26,880 hemisphere type image here. 50 00:03:27,340 --> 00:03:31,780 So what we're going to do know we're going to overlay these images and using some bitwise operations 51 00:03:31,780 --> 00:03:35,050 to illustrate the different type of operations that we have. 52 00:03:35,530 --> 00:03:36,650 So let's get to it.