So hi, I'm Fred. I wear two hats. I'm the product manager of Big Blue Button and I'm also the CEO of Blindside Networks. We are the company that started the Big Blue Button project. What I want to do is talk mostly about AI and how AI is basically informing our thoughts about how to evolve a virtual classroom platform in a way that effectively helps a teacher teach and a learner learn. I have thought and been thinking a lot about AI and this stems from when you build a product you have to start with the end in mind and I'm going to talk about the goal of the virtual classroom and I'm going to give you a framework for how to think about AI. So when you hear people tell you AI is going to make learning easy, no. AI is going to have a different effect. My opinion if you want to achieve effective teaching and learning in a virtual class and I wrote an article early this month, early this year on it about chat GPT to kind of think through these ideas. All right. So Blindside Networks, we started the Big Blue Button project in 2007. We work with over 25 Moodle partners and we recently have done since COVID over 2 billion minutes of virtual classes. Cool. And Big Blue Button, it's a platform. It's a platform for teaching effective virtual classes and it's not a video conferencing system. There's just so much more that has to happen during a virtual class to be effective. Video is a component, but only a small component. And if you just rely on video, you're kind of like looking through the keyhole or all my students there and that it's not an effective way to teach. If it was, all those courses and classes taught using video conferencing systems during COVID would have turned out much better. Okay. So why does Big Blue Button exist? Can I get a show of hands? Who thinks they know what this picture is? Anybody? Okay. No. I'll give you a hint. Anybody? The pale blue dot. That's the picture that Voyager took before it left our solar system and sent back. It took about two months to transmit it back. That's us. That's the pale blue dot by Carl Sagan in the middle of the cosmos. That's all we've got. Right. So when you think about how can we make sure that we take care of that in a society and plan it around, what's the roadmap? Well, the United Nations or UNESCO has the roadmap. Sustainability Development Goal number four is education and education underpins almost all these other challenges that we have. So it's critical for us to make sure that education is universally available and of high quality. It's how we're going to move our planet and our culture forward. We're not doing so well. Right now today, according to UNESCO, 244 million kids under 15 do not have access to education. That's just unacceptable. And I believe in the vision of Moodle to make our planet a better place for everybody and to provide educational tools as open source. And we share that as well. Okay. So what I want to do is I want to give you and answer a couple of questions like what's an effective virtual class? How do we measure this? And how can AI help at one and two? And again, I want to make this a bit of interactive. Let's imagine you are designing a world-class online school. You're using Moodle and it'll have virtual classes. You'll start off in Moodle, you go into a virtual class and you'll come back to a class. You want your teachers and students to say that was the best virtual class that I ever had. How do you achieve this? Anybody throw out some how do you how do you get to that point? What would you do? Basically, think about that problem for a moment. How would you design an effective virtual classroom so that it was going to be the best experience people ever had? That's the challenge that we have. And we thought a lot about this. So I'm going to tell you before I talk about AI, I'm going to give you a framework to think about what makes an effective virtual class. Otherwise, when someone comes up and tells you, hey, this AI is going to improve learning, how do you think about it, right? You have to have framework, a theory of the case. The second, I'm going to show you how we as a Big Blue Button Project, the myth line of that framework. And then I'll talk about AI. Okay, so AI is about improving, improving, sorry, a framework is about a virtual class is really about how do you achieve effective learning outcomes. So we should just sit down and imagine things, right? No, there's pedagogy will tell us this. And the one way to think about it a classroom is if you do video, it's a component of an effective virtual class, but the actual part of it is much, much more. The goal of the virtual classroom is not to meet, it is to learn. So what does learning mean? Again, should we just imagine it? No, there's like 50 years of pedagogy that already tell us how our brains work, how to teach effectively. So what can we learn from that? Okay, can anybody tell me what this diagram is? It's Bloom's taxonomy, right? So it tells us that we learn in stages, our brains work through stages. And if you look at this, that middle stage is all about applying, you can't master something, you can't be creative, you can't get the skill unless you actually have applied it. And of course, this makes sense, right? It's like walking into a gym and saying, I'm going to improve my physical fitness, and I will watch and look at the machines. I won't look at the weights, I won't lift them. No, you have to do things. You have to exert yourself. And if you continue down that road, what you really want to do is have a virtual classroom like this. So this is our framework for a structure of an effective virtual class. You start off the beginning with some building relationships, because you have to make students feel comfortable to make mistakes, right? Mistakes is part of learning. It's how we learn. You would do a little bit of review at the class. This is you, the instructor. Make sure you understand where the students are on their learning journey. Introduce the material. The main segment I'll talk about in a moment. Summarize the content, ideally get them to summarize it, and then talk about next steps. During the main segment, you want to have small chunks, right? Micro learning. You want to create a scaffold so that you can get students to apply what they just did, right? So think of this in contrast to where you're typing stuff into AI and it's telling you the answer. No, you want students to apply themselves because if you work your brain, that's how our chemistry works, right? You have to think, you have to apply yourself and struggle is good. So these applied learning is a way that you actually climb Bloom staircase, and then we have this cycle which we have called, we call it the virtual cycle of applied learning. You apply yourself. You exert effort, right? You struggle a bit, struggle is good. You get feedback. You get that level of understanding, and you keep doing this. And what you want to achieve from the student's perspective in your world-class online course is they come to the virtual class and they realize the more I apply myself, the faster I learn, right? And so what does it mean to do effectively apply yourself? Well, again, there's a theory for that. Velosky's sown of proximal development. What a name. And it basically says, okay, am I, yeah, thought the internet had got me. You have this task which is either too easy. If I asked you what 2 plus 2 is, everybody would say 4. If I asked you 475 plus 376, I always wait to see if someone just yells out the answer. There's a zone in there where basically it breaks down to at the lower end and the higher end. So at the lower end, these are things that are achievable by yourself. You could sit down and figure it out. You struggle a bit and struggle is good. At the highest end of the zone is the things that you can achieve with assistance, right? So think about you're in a virtual class right now. You're not by yourself and that assistance can be from the instructor, the teacher or from your students, right? So what's that theory based on? Well, that's social constructivism and that's what Moodle is based on. Moodle is based on a theory that we learn better by working with each other. Why? Because we're human, right? Humans learn best from humans. I can have things that help me set up an environment but at the end of the day, I have to apply myself and I want to learn and I will learn best with helping. That's what the zone of proximal development tells us. Okay. So all of that, I want to boil down to the one phrase I want you to remember. If you want to have an effective virtual class or effective learning any classroom, you ideally want to create the most space in the class where the students apply themselves and get feedback, right? So think about any time that you work with somebody and you have this really great experience, right? They probably helped you over some block and maybe you didn't even know what you didn't know but they helped you over the block.  That's the experience that you want to get out of a virtual class. It's not a passive watching hour of someone talk, right? There's pieces of that that are necessary to create the scaffolding but you want to be apply yourself. Okay. How do we implement this feature? How do we implement this framework in our product? This is what's guiding us, right? So that we're not building a video conferencing system. We're building a virtual classroom. And we look at it as like a before, during, after. So you're in Moodle. You go into Big Blue Button and afterwards the recordings are available. So we took the virtuous cycle of applied learning and we just basically said, how can we help the instructor? Well, you build in tools for the applied learning, right? Every time I hear somebody use a video conferencing system and describe how they take students to this website to do this type of interaction and that website, it's like, that's because your platform has no idea what you're trying to do. It's just sharing bits. It doesn't know what the goal is, right? The goal is to learn. So we provide built, we built in capabilities. The teacher can get the students to apply themself. Those generate analytics and then we give the analytics back instructor live so they can see who's struggling to give them feedback in the moment. So some visuals. This is from the product. So in breakout rooms, for example, you can get students to go into breakout rooms. We'll automatically capture the content in breakout rooms, bring it back to the main room and we give the instructor the ability to monitor the breakout rooms as well. You can open them up in individual tabs and just jump back and forth between to see who needs help. We have this visual assessment. You can have multi-user whiteboard and you can have the students, can you please point at me where France is? And they can't see each other's pointers, right? So you're getting them to think and you visually see how is the class doing. So it's a type of formative assessment. Are they getting the concept? Can I move on to the next? Have I built something that I can build upon? And the other is we have something called smart slides where if you upload content and we see a question mark with some comments after or some ABCD, we just say, hmm, I think you're trying to do a poll. Well, rather than make you type that poll in, we already have the text and memory for screen readers. Let's just generate a poll. So we'll give you one button and you can create a poll and when you do that, the poll will go to all the students and you get the responses back live. Okay, you've got them applying themselves. You're getting them to get you feedback, but we're also doing analytics, which means we're aggregating all that into like a dashboard. We call it the learning analytics dashboard. It's live during Big Blue Button. And what it does is it tells you where students' activities are, like how much effort they're putting forward, right? Because effort is a proxy for learning. We're not measuring learning, we're measuring effort. So the example I always give is here at the bottom. You've been doing some poll questions. You kind of got a sense of what the class is doing and you see that Sam isn't responding to all the polls. So imagine as a teacher, you say, okay, I need everybody to respond and Sam, don't worry if you get it wrong. Make the effort. This is how you'll learn. And Sam would be there like, what? The teacher's aware of me? Yes, because you're not relying on webcams to see, we're going to give you the data based on their activity. And that's the difference between us and a video conferencing system. Okay. So now I've given you a framework to think, like maximize time for applied learning feedback, a bit about how we implement that. And now let's explore how AI. So now with the framework, we can be a lot more precise, right? Like we can sort of think about, okay, if this is an effective virtual class, then we can ask ourselves, how can I improve teaching and learning in a virtual class? And let's go back to this. So if you look at this, you can start asking the question at what points along the way can AI assist the teacher? And if you ever hear someone say AI can make learning easier, I want you to really think about, okay, wait a minute, our brains are the same. They haven't changed, right? We have to think, we have to struggle, struggle is good. It's how we learn. If there's no struggle, there's not a lot of learning that's going to go on, right? If you don't apply yourself. So first thing is, well, you can pass in information from Moodle that's going to help the teacher identify which students are struggling. And an example would be if when, as Moodle has more analytics, right, as a better understanding of where students are on their learning journey, that information should come into you as an instructor during your class, like why manually look it up. So we've been exploring this. So this is an example like imagine and be glue button. You have like a little warning sign next to a person's name.  So the system is helping you understand where students are so that you can better teach them live in the virtual class. That's because it understands the goal of the virtual class is to not to meet, it is to learn. And we're trying to achieve this as a first step through sub-plugins. They're still work ahead, but in the built-in integration with Moodle, so big blue button is in the core, we're adding the capabilities for sub-plugins so that we can easily extend the capabilities of big blue button in Moodle without having to like modify the core of Moodle. It's like how the quiz modules and other modules do it. So we want to innovate faster and get more useful information out of Moodle. Number two is, well, you can generate quizzes based on the content of the slides. So I showed you a few minutes ago smart slides where it kind of figured out there's a question there and there's a couple options. Well, with a large language model, if the instructor is like staring at the slide and wondering, are the students getting it, they could ask them a question and say, okay, I'd like to generate that you could use AI, which we could send the data in the background to a large language model. And because of the open source language models, you can imagine this not going to Google or elsewhere and generate a poll question. And it would do it on the fly and you could regenerate it. And then you could just say, get the information back from the students, use a learning analytics dashboard and see if the students are learning. So this is not making education easier for students or learning easier. Learning should be challenging and effortful. You have to think. You need to get students to think. This is saving the instructor time so that students can spend more time trying to apply what they're learning and get the instructor feedback to see how they're doing. That's the North Star. The third one, we generate a lot of recordings in the virtual classes. But we don't believe students are referring back to these virtual recordings. Why? I mean, the information was there. It's hard to search, right? It's hard to index. You can't find things. So you imagine you use a language model to summarize, like text to speech, read the slides, figure out the keywords and then index that. So if a student wants to find out, okay, where did we talk about Pythagorean theorem, they could get to exactly that part in the class and review it. Another one is if you have content that's generating the class at the end, spaced repetition, right, so you could use AI to create quiz questions that go back to the students between like this Thursday's class and next Thursday's class and just have them recall the information, right? Again, you're exercising the brain. These are like small workouts. Okay, so now I have a question for you. If the virtual classroom used AI to summarize a lecture at the end, would that help learning? Anybody? Yes, it would. Okay. Do I hear a contrarian opinion? Could we do better? You are on the right track. So research shows that taking notes during the class is not as effective as at the end of the class taking the notes and trying to recall what happened in the class. So a more effective use of AI would be is have the platform ask the students for like, what are your two key takeaways and have AI help filter that for the instructor so they could see if these are effective and then summarize those back to the students. So you get the students to spend two minutes thinking about, okay, what was the most key two key points in the class? And then the platform helps you organize that and give it back to the students. That is a more effective way of AI. So this is where I come to when you hear someone tell you AI is going to do this for you and that for you and that for you. Think about you're working, you're walking into a gym, right? You're working out to improve your health and fitness. You can know about how the body works, how nutrition, you've got good sleep, you have all the right equipment, but you still have to pick up the weights or you still have to do the exercise, right? Our bodies haven't changed or minds haven't changed, but you can have a teacher or a coach there that motivates you. And now this is getting closer to where I think AI can liberate the teacher in some way. Right. So the question was verify the accuracy of the summary and that's correct. That's why I said the students will give you the feedback. AI can help filter it, but before you show it to students, the teacher can vet that to make sure that this is correct, right? So the AI is just assisting the teacher. The students said, you know, like, I'm tired. Okay, the AI can probably figure out that's not a summary of the lecture. But the goal is to assist the teacher by creating poll questions on the fly by vetting the summary for the students and maybe get to a place where you generate activities. But you are not jumping in in front of the teacher. AI should be an assistant to the teacher. It does not replace the teaching. AI should be an assistant to the student. It should not replace the student. If we ever get to that point, we're going on the wrong path. Okay, so I'm going to I'm now going to put my mind forward and I'm going to say this is where I think the future of teaching and learning is kind of headed towards in steps. And I call this personalized artificial general intelligence tutor or pageant for short. So imagine you do have an assistant that understands where you are and helps you on an individual. Like just think of what show of hands how many people had a tutor throughout their educational career. Okay, a tutor like a personalist, somebody who came in and said you're struggling with something like could be a math problem. And they basically said something like this. Look, I see you're struggling. Don't worry. I'm going to help figure out where your gaps are. I'm going to get you to overcome those gaps of knowledge.  Okay, the tutor doesn't walk in, take the piece of paper, write the answer, give it back and walk out the door. Right, there's no learning there. So this is where I think AI can really help the student and the teacher. So I'm going to go back to pedagogy for a moment. You have two states. I want to learn this. And with effort, I get to I get to a place where I mastered it, right? Seems like a straight path. No, it's not. So you think about like climbing bloom staircase where you get to mastery, you do this over a series of times, we'll call them learning workouts to use the analogy, right? So you have to do things, apply yourself, apply yourself and then you get to a mastery. It takes time. Well, let's say you want to do a task. There are probably some prerequisite knowledges that you need to know. And in this knowledge, you're going to be at different stages and bloom staircase, right? So this is the problem we all run into. We're learning something. We don't know what we don't know, right? So think of the time in your past where you were struggling and you're just hitting the wall over and over again. It's like, why can't I get this? Well, it's probably because something that was taught earlier you need to know something and you didn't have that piece of knowledge, but you didn't know you didn't have that piece of knowledge, right? So a really good tutor, a human tutor would look in and say, where are you? Okay, here's the underlying knowledge that you don't have. Let's get that in first. If you do this, I believe that I believe in AI can do this fairly well. It can figure out the gaps in your knowledge. It can help you do it. It can give you exercises. It can check them, but it would never ever tell you the answer. You have to come up with the answer. It can only coach you and help you. And if we do that, imagine the analytics that are created, right? So imagine we're all in a class together and I'm trying to teach you, right? There's like 100 people in this room. Everybody would be at a different place in their learning journey. Today, I would just teach the room. I would go to the medium and say, blah, blah, blah, blah, blah, blah, and half of you would be below, and half would be above it. But if I were able to see where you're all in your learning journeys, I can start doing some really, really powerful things. So I could get a dashboard to see, okay, is this particular part that everybody needs to know, like 80% of you to have a gap? I should probably spend about 10, 20 minutes making sure that gap is closed and the next gap is closed. So what is this data letting me do? It's not changing how I teach or learn, but it's helping me teach more effectively and it's helping you learn more effectively. And if we can get these analytics in Moodle and share them with Big Blue Button, then I think we'll have a platform which, again, is not going to go into the gym and pick up the weights for you, but it's going to set it up so that you have the most effective use of your time. And that's what a personal tutor would say, trust me, we're going to get through this and I'm going to help you have the most effective. It also talks about the role of teachers. So let's imagine this world exists. What is the value of the virtual class? I would argue it increases. If on our own we can interact with someone, if we tilt the laptop and the camera sees what I'm writing and uses AI to get my handwriting and the avatar is talking to me and says, Fred, you can do this, right? When I go, I would argue that the virtual class, the human-to-human interaction becomes even more important, right? Because we're humans. It also fundamentally, I think, enhances the role of the teacher. So the teacher, I think, becomes more like a coach. Less of, I'm just going to digitally give you the information and you're going to listen to me for an hour and that's learning. Well, that's industrialized learning. I think the value of the virtual classrooms is the teacher becomes more like a mentor, encourages, you know, supports you, challenges you, rewards you, and I think a piece that's missing in our system is that make sure that you work really well with each other, right? Because that pale blue dot, the problems we have right now are not going to be solved by individuals. They're going to be solved by people that are actually really able to work together. And so I think the teacher's role is more of a mentor or a coach that makes sure people are really good at applying themselves, getting to that level of mastery and working well in teams and with groups. Would you like to introduce any questions? Yes. So to summary, I want you to have this framework in your mind, maximize time for applied learning and feedback. This is what you're trying to do as a teacher and a learner. We built a product around this framework. Learning takes effort and you should not reduce this effort. You just set the environment up so you can have a very useful and efficient effort, but you still need the effort. Thank you. Thank you. We do have time for a question if anyone likes. Obviously, you can speak to Fred and the others on the booth as well, but anyone want to ask a question now? Yep. Just one done over there. Hi, Fred. Like most people, we use big blue button when the pandemic hit because we suddenly needed a solution. Pandemic dies down a bit. Company reviews, we go back to Zoom. Listening, and I've got no issue with that, but listening to this from a pedagogical perspective, myself and my colleague here are 100% committed that we go back to this. From a costing perspective, and I know it's integrated into Moodle, but I have to ask the pricing plans, is that still a feature based on user numbers or how does that side work? Or is it just, it's now integrated, that's it? So the question is about pricing in that. And look, I'll put my big blue button hat on. It's open source. You can run it like you can run Moodle. I'll put my blindside networks hat on. We, the company, generate revenue by providing hosting. So come by the booth. We do base a hosting on concurrent session, not named user. We try to make it cost effective. And my goal is to keep focused on what I've shared here. Like I'm never trying to out team teams or out Zoom Zoom. And thank you for that feedback, right? I mean, I know we're on the right path and AI is going to make things easier, but it should never replace the actual role of teaching and learning. 100%. It's awesome. Well done.


You're destroying me financially. Over a Batman toy, from 20 years ago?  There's nothing funny or heroic about it. But what if we flip the script, and turn the victim into the villain? In this episode, we'll go into the world of revenge on bullies, with 6 real stories. So grab some popcorn, and get ready to watch some serious karma play out. Will justice be served, or will the revenge be even more sinister? Before we start, gently nuke the like button into oblivion. Warning, these revenge stories, might be upsetting to bullies. In third grade, I was an awkward kid who had a hard time fitting in and making friends. I mean, drunk dad didn't make things any easier, and I was often bullied and left out by other kids. One day, a classmate named Derek, who used to bully me too, suddenly acted nice towards me. Since I wasn't used to kindness or attention, I quickly trusted him. Derek spent recess with me, which was when I was usually alone. We laughed, talked about girls we liked, and he even said sorry for being mean to me before. The reason he was being nice was because I had brought a cool and expensive Batman action figure to school. I had saved my allowance and mowed lawns for two months to buy that awesome toy. Everyone wanted one. At the end of the day, Derek asked if he could borrow the action figure. Being innocent and not good at social stuff, I let him take it. He agreed he would give it back the next morning. I went home so happy, totally fooled, and never suspected a thing. The next day, Derek ignored me completely. When I tried to talk to him, he acted like I was crazy. When I asked him to return the action figure, he simply said, You never gave me any Batman. Maybe you imagined it. When I persisted, he threatened to beat me up. When I complained to my teacher, I was told that it was my own fault for bringing toys to school. I was afraid they would involve my father, so I dropped it. I couldn't let my father know or he would call me a loser, beat me, and punish me for the next two weeks. What's worse, is Derek told all the girls that I confided in him about fancying, that I was simping over them and I would fantasize about them. That I was obsessed with some of them. Before all this, I was a social outcast, but at least I was tolerated. After Derek's smear campaign with the girls, I was like a leper. People wouldn't even look me in the eyes, not even the teachers. Kids started throwing stones at me, sabotaging and vandalizing my belongings.  I did nothing about it but cry. I was just a weak-willed kid after all. But to this day, I wish I'd done something, anything in retaliation, like biting someone's ear off. Eventually, the bullying died down, and I focused on my studies, which led to good grades. Derek tried talking to me again, but I ignored him completely. As he would say.  You didn't give me anything, you imagined it. By the end of the year, we moved houses, and I transferred to another school not far away. Things were much better there. I finally had friends, and I wasn't as naive, so I wasn't targeted as easily. But I was still mostly the same person and got picked on now and then. Over the years, I became somewhat of a delinquent, and in high school, I got into regular fights. I'd been overcompensating for my lack of backbone in my younger years. In my early 20s, I bartended in nightclubs, hotels and cruise liners. This helped me become more socially adept and understand social dynamics and human nature. I finished trade school and qualified as an electrician and later as a plumber. I know, water and electricity, but believe it or not, I thought it was ingenious at the time. I started my own business and developed a reputation for excellent workmanship in my local area. Things were going well for me. When I was 29, I'm 36 now, I received a call at 2 in the morning for a flooding emergency at a local residence. When I got there, the place was a mess. Water was jetting out of a burst pipe, electrical equipment was shorted, and the situation was highly dangerous. The living room floor had even caved in due to a sinkhole. I was met by the wife, let's call her Susan, who was hysterical and beside herself. She somehow thought she was responsible, which I found odd. I assured her that it couldn't possibly be her fault. Not five minutes later, he arrived. His demeanor was irate, and he didn't greet or shake my hand when I offered. I recognized him immediately. Derek from all those years ago. He demanded to know why I hadn't started fixing the issue yet. I remained professional, told him what I had told Susan in terms of costs, but I hid the written quote in my vehicle. I revealed who I was and acted happy to see him, assuring him that he was in good hands. After a while of arguing with his wife, he seemed to calm down and even joked around with me. I knew, I had fooled him. We talked about our careers, kids, and school days. I gave him tips and fake recommendations, and we got along great. Gaining his trust was easy. He must have thought of me as a complete sucker. I assured him that he was in good hands, and the issue would be fixed in no time. I was careful not to start any actual work on the property, as doing even the smallest thing would make me responsible for all of it. After an hour or so, Derek left, and his wife stayed behind. A vengeful brainwave entered my mind. I reflected on the years of cruel torment he put me through. This opportunity was placed onto my lap, and I shall maximize its potential, by pressing the nuke button. During my assessment, I noticed that most of the building didn't comply with city regulations and didn't adhere to the registered and approved plans. There were multiple safety hazards, and all plumbing and electrical work had been completed by unqualified and uncertified people in an attempt to save money. Also, the pipe in question had been leaking for at least a few weeks, getting worse by the day and finally causing disaster. This meant their water bill would be astronomical at the end of the month, unless a qualified plumber endorsed a rebate with the municipality. I called my contact at the city, let's call him Donovan, and notified him of all the regulatory violations, safety hazards, and non-city compliant installations on the property. I also told him about the potential water bill. He promised to be there the next day. I immediately started photographing and documenting everything. The following morning, Donovan arrived at 10, and he had a field day. He informed Derek's wife of the calamity that was to come. They would be forced to tear down all the building additions, remove all the uncertified plumbing and wiring installations, have the plans re-approved, and start from scratch, which would result in an estimated loss of approximately $120,000. Derek arrived in minutes, livid. He quickly threatened legal action, but Donovan simply told him, Listen, we have more than enough photographic evidence, to have the property declared invalid within a week, if you don't comply in writing. Donovan reminded Derek, that he did this for a living and that the city had more legal resources to waste money on. I left Derek an invoice for my time, just to rub salt in the wound, and took my leave. Later, Derek called me and hurled every insult imaginable at me. I remained silent, and he eventually hung up. He went on a Facebook rant about me, which turned out to be a bad idea. The entire community stood up for me, and it started a storytelling competition, where all kinds of people revealed unsavory things Derek had done to them in the past. Apparently, Derek had always been an unpleasant person, and he never changed. One day, he called me and asked to meet. He sounded defeated and depressed, so I decided to meet and see what was going on. I met him at a local, busy convenience store. I knew better than to take Derek the weasel at face value, so I quickly noticed when he placed his phone screen down on the table. I suspected he might be recording the conversation. To my surprise, he apologized for his behavior and told me that the whole dilemma had all but bankrupted him. He explained that he had taken out a loan for the building additions and cut corners to save money, claiming that everyone does it. He showed me the water bill, which was nearly $80,000, a problem that could easily be erased with a qualified plumber's signature and endorsement. I refused. He became our aide again. Then he asked me. Why did you do this, to me?  But I don't deserve to have my and my wife's lives ruined. Because of mistakes I made when I was a kid. What kind of person are you?  You quoted me only a few hundred, and told me not to worry. I replied. I said no such thing. Derek insisted. Stop lying. You told me that it would cost a few hundred, maybe less. I heard you say it. You promised to help me, gave me recommendations. Why are you doing this to me? I said, Derek, you must have imagined it. I looked him in the eye, and he knew exactly why I said that, the same thing he told me almost 20 years ago. I repeated it just to drive the point home.  I never quoted you for anything. You imagined it. He knew I was destroying him financially, because of a Batman action figure he stole from me 20 years ago. I could see it in his eyes, but he couldn't bring himself to say it. His expression was a mixture of astonishment and pure disgust. I looked him dead in the eyes for a few seconds for effect, then got up and left. I slept like a baby that night and had a goofy smile all week after. He tried calling a few times, but I sent him a text stating that further harassment would be met with legal action. Derek, you know what your real name is, and what mine is. If in the future you read this and realize how I nuked you, remember how costly that little Batman action figure was to you, after years of accumulated interest in karma. The look of despair on your face when you realized why you were ruined, was delicious. I cackled maniacally on the drive home from that convenience store. It was time for you to pay the piper. And if you think this will help you legally, go ahead and try. It won't, so don't waste your time. Or rather, do waste as much time and money. I welcome being even more of a financial inconvenience to your life.   This deserves a chef's kiss. Did he ever end up taking legal action? Also, I hope you were able to get a new Batman eventually. No, he couldn't take legal action against me. I made sure to cover my bases by documenting my assessment, taking notes, videos, and photographs as evidence. I didn't do any work on the property, because that could make me partially responsible. Donovan cautioned him against making the situation more challenging. If he fought back, he'd be up against the city, not just me. Being registered in the city database, I am technically a representative of the city council as well. Dear sir, from all the people who were bullied as kiddos, and all of us who have grown up dreaming of nuclear revenge like this, I thank you. I'm never going to get revenge on the people who bullied me or stole from me, but I pray karma does build up. I'm so glad you were able to see yours and use the exact same wording. I feel very peaceful after having read your story. Wish the bank's interest rate was as high as the accrued karma rate on this torching. Almost feel bad for Derek, almost. What I admire here is your amazing restraint in that final encounter. I'd have dug for more gold at my own expense, really. You were unkind to me in school. Now so? Which would have just opened cans of worms and doors to counterproductive engagement? You did none of it. You left it all unsaid, except the key line. Amazing. I witnessed this unforgettable incident a long time ago, and the story spread through word of mouth. Once upon a time, there was a kid named Harry. He was an ordinary, slightly skinny, and somewhat geeky child. I can still recall how he had a knack for disassembling pens if they were left unattended. Like this peculiar habit, Harry was nice, polite, and always willing to lend a helping hand. This all took place during middle school. One fateful day, Harry disassembled the pen of a notorious bully named Brad. Brad was a massive, chunky figure. He looks like if you drilled three holes into him, a giant could use him for bowling. He was far from friendly or charming, and he led a group of equally repulsive friends who teamed up to torment others. I often wondered if they banded together to avoid being bullied themselves, perhaps driven by a newfound sense of power. I usually kept to myself, but one day, I noticed Harry sporting a swollen eye, damp hair, and a slight limp. His backpack was torn, too. Concerned, I asked him what had happened. He explained that Brad had violently flung him into a bathroom stall by his backpack, causing it to rip. The impact with the toilet had injured his knee, and Brad had ruthlessly dunked his head in the water, slamming his eye into the seat. When I asked Harry why Brad had done this to him, he simply replied, I took his pen apart.  Over the next few weeks, the situation escalated.  The school, filled with your typical fartfaces, tried to expel Harry for damaging school property, while leaving Brad untouched. However, video evidence of Brad and his gang laughing and rifling through Harry's backpack saved him from expulsion. When Harry returned to school, he was a changed person. He became quiet and withdrawn, and bruises seemed to appear on his body between classes. He grew increasingly thin as he retreated into himself. The school staff turned a blind eye to his plight, but one compassionate jock stood up for Harry. He caught Brad stealing Harry's backpack and retaliated by shoving Brad into a trash can. Though the jock was suspended, he continued to protect Harry after returning, and his parents threatened to sue when the school tried to punish him again. Seeing someone stand up for him seemed to breathe new life into Harry. He gradually became more open and started to regain weight. One day, he wore a beautiful knitted scarf that his late grandfather had made for him. Brad, still relentless in his cruelty, stole the scarf and returned the next day with a bag of ashes, laughing maniacally as he handed it to Harry. In response, Harry came to school with a backpack full of sugar-free Haribo gummy bears. Brad, unable to resist and the glutton he is, stole and devoured them all. As Harry cried, I noticed something off in his expression. Something in his sobs, didn't quite reach his eyes. Near the end of the day, Brad suddenly rushed to the bathroom and didn't return for several days. Rumors circulated about actual blood found in the bathroom. When Brad finally came back, he wore an eye patch and had modeled, meeting bruises across his face. He had permanently lost vision in his left eye, and the bruising made him resemble ripening fruit. Brad became introverted and quiet, and he never bothered Harry again. He frequently left school for doctor's appointments. While the reports of blood in the bathroom were never confirmed, it seemed quite likely that the sugar-free gummy bears had exacted their revenge. A five-pound bag of Haribo candy is 2,268 grams. The nutrition panel shows that the first, and thus most prevalent, ingredient in the sugar-free variety is lichocin, which is mostly maltitol, a sugar alcohol. 40 grams of maltitol for an adult is enough to give you the runs, if you're sensitive. A bear weighs around 3 grams. That comes to about 20 bears to get your guts bubbling. For some, as few as 15 sugar-free bears did the trick. For a kid it would be even fewer. According to the manufacturer, the maximum recommended amount per day is 100 grams for adults. So if one dumb kid ate a whole bag of Haribo, he would have ingested more than 1,200 grams at least, of maltitol in one shot. That's one wet rocket ride to hell, oh boy. I hate how many bullying stories include schools punishing victims. I got bullied too, the school knew. They did nothing until things got physical and I got the same punishment as the bullies because, they can't tolerate violence. No exceptions. You know how some folks with autism are said to have special gifts, like in the good doctor or rain man? Well, turns out I actually got one. Not that I'm a genius or anything. My gift? Drawing. Yep, I've been scribbling away since I was in diapers. While I'm no Da Vinci, my drawing stood out even as a kid. My kindergarten creations looked like they were made by fourth or fifth graders. And as the years went by, I kept at it. Being on the spectrum gave me the superpower to obsess over my passion without ever getting tired. I mean, I had art blocks two to three times a year tops. My classes usually had bad teachers and many of my classmates struggled, especially with English. But hey, that was my jam. I devoured books like they were candy, especially graphic novels. I'd breeze through schoolwork and find myself with plenty of free time. To keep the grumpy teachers at bay, I hatched a little plan. I'd secretly offer to do assignments for my classmates, as long as they'd show me a sample of their handwriting. You see, I was no stranger to bullying, and being known as the art kid didn't help. So, I'd whip up some cool fanart of whatever book we were reading to keep things interesting. This little arrangement worked wonders. I did their homework, the teacher stopped yelling, and the kids gave me some breathing room. It was a win-win situation for everyone involved. Unfortunately, there was this one bully with family troubles and a stutter who decided to pick on me for my disability. Say hello to Jack. Starting in the sixth grade, he made it his mission to torment me. Jack was always up to no good, causing chaos during lunch and after school. He doodled naughty bits in the social studies textbooks and pull pranks on other boys. His crude comments and insults were dished out to everyone, but he had a special fondness for targeting me. He made fun of everything, from my dietary restrictions to my lack of coordination during recess. And if I dared show interest in, another student? Jack would rally the whole class to tease me relentlessly.  And heaven help me, if I kept up with my Nintendo obsession in sixth grade. Jack just couldn't get enough of making my life miserable. It was as if my Mario merch had a giant bullseye painted on it. My lunchboxes were destroyed simply because I was too old to bring them to school. Keep in mind, we were only 10 to 11 years old. And that wasn't all. Jack would often tear up my drawings or leave his own rude sketches in my notebook. Despite our numerous scuffles when no teachers were around, nothing seemed to put an end to Jack's torment. Telling on him didn't help either. But then, something happened that pushed me to the edge. The assistant principal gave me a copy of the Hunger Games, which I devoured in three sittings. I was in love with the story and even tried drawing Katniss. But one day, I made the mistake of leaving my book unguarded during lunch. When I opened it later at home, I discovered crude drawings on the inside cover and boogers on some pages. I was furious. I ranted to myself, who does this to books? And the teachers won't do anything, either. Fuming, I turned to the living tombstone for solace, as any angry preteen would, and tackled my homework. When I opened the social studies textbook I'd brought home, there it was, another inappropriate drawing by Jack. I remembered he'd been in trouble for this before, and suddenly, a lightbulb went off in my head. I had an idea. I swear to God, the grinch smile just slid onto my face. I had done homework for Jack before, so I knew his artistic style all too well. I rolled up my sleeves and started imitating his doodles on the inside cover of a textbook. Using my left hand to capture his messy handwriting, I added some silly phrases I can't name here, and drew mustaches and spammed male parts on, historical figures. Our classroom had a mountain of textbooks, way more than there were kids. They weren't assigned, so everyone just grabbed one from the shelf. No one would notice if one went missing. I smuggled the artwork back into the classroom, and the textbook heist began. Over a week, I took more textbooks home, repeating my masterpiece in each one. The cherry on top? Drawing Freddy Fazbear on the entire inside cover of a textbook. Back in June 2015, everyone was watching Markiplier and waiting for the newest part. I was super cautious, trying to make it look like Jack's creation, not mine. He drew people with row blocks like proportions, so I sketched a tall, wonky Freddy Fazbear, using pencil first and then wobbly Sharpie lines. That bear stared right into your soul, just like Jack's doodles. I couldn't help but laugh at my handiwork, that Freddy was just too funny. If only I'd had a phone to capture the hilarity. Plus, it was a character from a horror game, totally inappropriate for school. I knew our teacher would lose it. And boy, did she ever. That Friday, I faked being sick to escape Jack's bullying after a particularly nasty incident during recess. My plan was to report the drawings to the teacher and watch Jack get scolded. But since I skipped Friday, things unfolded differently. When I returned on Monday, Jack was nowhere to be found, not even on the bus. It turned out that on Friday, our teacher had asked the class to open their textbooks for a lesson, not homework. Several kids discovered the vandalized textbooks, including the one with Freddy. Jack got into major trouble for defacing so much school property. After all, it was clearly his handwriting. He was suspended for the rest of the year. I knew Jack's grandma was his guardian, and she was the only adult who took my complaints about his bullying seriously. She would have been furious about his vandalism. I never expected things to go this far, but with Jack moving, in August or September, I'd effectively rid myself of him for the rest of June. I wasn't complaining one bit. I had pretty much accidentally gotten rid of Jack early. My teacher was still gathering information from other kids. Some had already seen him doodling in the textbooks and told her, making him look guilty. And now, she finally got a chance to ask me about it.  Jonah, have you got a moment? See me in the hallway. Me, a well-behaved, short, and adorable fellow with big, nerdy glasses and messy hair, replied, Yes, ma'am. Have you noticed any drawings in any of the textbooks? Aha, I said. What kind of drawings did you see? Um. There were a lot of poopies and peepees. Okay, turds and peewees, yes. Do you, by any chance, know? Oh, and I saw a robo bear in another one. Right. Do you know who was making these? This is vandalism, and it can actually be considered a crime. Aha, I already know it's Jack. He draws weird stuff on my stuff, too. Can I show you my doodle book? Look, it matches. I ended up showing her my notebook. I had stopped bringing Hunger Games to school because Jack kept smacking it out of my hands in the hall. And amongst all the crayon drawings of Megala and Zero squared from Kirby, etc., she saw some more rude doodles that didn't seem to be mine. She seemed pretty mad, but not surprised. I don't remember the entire fallout, nor was I there to witness much of it, but I heard from other kids that Jack had to face the school board because it involved multiple books and was really, really bad. Apparently, he kept crying to his grandma, claiming he didn't do anything. I stayed quiet but smiled to myself throughout the last two weeks of school. He ended up moving to Florida shortly after, so I basically got rid of him for good. Moral of the story, if you're going to vandalize another student's property, maybe don't pick a good artist who has experience copying others' handwriting. Oh, and drawing bad freddies is hilarious. Now that's some professional revenge right there. You shall hereafter be known as the forger of PPs. Amazing, I'm honored. As a kid who was bullied for drawing MLP in middle school, this story makes me feel good, and I didn't even exact revenge on my bullies, cheers. This is really funny to hear because Jack actually was a brony in school for a bit. So was another one of my bullies as well, my worst one had a Pegasister phase for a while. Jack though, he'd walk in with this tiny pink MLP wristband sometimes like a year or two before this. MLP was seen as cool in my class thanks to the horrifying creepypastas and smile animation. Do we live in some kind of parallel universe or something? I practically got bullied into watching it. I'm so glad I read the whole thing, this is great. As someone who was undiagnosed autistic and ADHD throughout school, and heavily bullied for being weird, this gave me a lot of secondhand satisfaction. There I was, watching the latest Spiderman flick with my buddies, all of us in our early 20s. The theater was jam-packed, but what caught our attention was a rowdy group of high schoolers, both guys and gals, seated right behind us. They were doing typical teenager stuff, taking flashy snapchat photos, gabbing loudly, and laughing like hyenas. You know the drill. In a half-joking manner, I said loud enough for them to hear, if they're this noisy during the movie, we're gonna have issues. They must have heard me, because they burst into laughter. Challenge accepted, I thought. Game on. 15 minutes into the movie, they were still yacking and driving us nuts. One of my friends shushed them, only to receive a muttered. And more laughter. That was it, the last straw. These punks thought they were untouchable, but now it was personal. I spotted a worker who seemed like a manager and knew I had to be crafty. Instead of just reporting their obnoxious behavior, I told him, there are some people behind me filming the movie. He nodded and immediately kicked them out. Their protests fell on deaf ears, because their loud chattering had betrayed them. The manager wasn't about to take their word over mine. They insisted they were innocent until he played his ace. I'll call the cops. Heads hanging low, they shuffled out of the theater. My friends and I watched the whole scene, grinning from ear to ear. The best part was that they felt cheated and angry, and there was nothing they could do about it. That made our sweet revenge even sweeter. Q DOS to you. I absolutely hate people who can't follow the rules while in a movie theater.   Going to the theater is one of my favorite things to do.  If I ever go back to the theater again and encounter this type of shenanigans, I'll use this amazing tactic. For those who are saying, that you're evil for ruining the night for a group of teenagers, their youth does not give them a free pass to be inconsiderate. They need to learn while they're young that they aren't going to get very far in life if they act this way. In reality, OP did them a favor. It is up to adults to teach youth what is okay and what is not. And even if it sucks for them in the moment, it really is in their best interest. Unchecked entitlement creates future Karens. I once had a similar experience with a chatty group behind me when I went to see Infinity War on its opening Saturday. I tried shushing them a couple of times, but they just wouldn't quit. Luckily, I'd already watched the movie on Thursday night, so I knew exactly when to strike. As the Guardians arrived at nowhere, I seized my moment. I turned to the kid right behind me, looked him dead in the eyes, and said, None of this is real. Thanos already got the reality stone and is messing with the collector's lair. Just seconds later, the scene unfolded on the screen, confirming my spoiler. One of the kids called me a jerk, but I had their attention. I faced them one last time and warned. Keep quiet, or I'll spoil the rest of the movie for you. Just like that, they didn't make a peep for the rest of the film. I've been playing Yu-Gi-Oh trading card game for a while now, and one of my favorite things to do as an older player is to help out the younger ones. I have different decks to teach them, and I often give them cards from my own collection to help them improve. I even give them advice on rules and building their decks. One day, a new face comes in and starts challenging the kids to games, duels, using this top tier meta deck that absolutely blows the kids' decks out of the water. I hate to admit it, but that's part of the game. Sometimes it can be a teaching moment for a newer player, to see what a deck at the top can do in a non-tournament atmosphere, and get a better grasp on what they can do with the cards at their disposal. But what really got my hackles was the trash talking. This guy was clearly in his early to late 20s, and some of these kids were 10 or 11. There were tears, and one little girl flat out threw her cards away and ran crying out of the shop. My knee-jerk big brother reflex kicked in and I sit across from this kid, ready to play.  The game grinds to a halt. I have him completely locked out of every play, I stop him cold at every turn, and there is quite literally nothing he can do as the game drags on at a snail's pace. He's getting more and more frustrated, and eventually he gives up and leaves. But I'm not done. I'm good friends with the shop owner, and word through the grapevine is that this kid goes from shop to shop in the area, preying on new players. I resolve to make sure he never pulled that on anyone ever again and proceeded to pop up at as many spots as possible to challenge him. Predictably, he wouldn't take me, up on it. And when he didn't, I called him out for his practices in front of his friends and peers, because this frikwit was basically a mark for himself and like to pick on newbies. A mark is a wrestling term used to describe a fan or someone with a grossly inflated image of their own skill and self-worth. It was a targeted campaign designed to drill a little humility into him, and it ended with him claiming to quit the game. Good. I don't regret it. This game can exist just fine without people like that, and I hope you learned a lesson about picking on someone your own size. I play magic the gathering and I hate when people do that. I'm not great at the game myself, but can't we just let people have fun? Good on you for stopping the negativity. This is a pretty small revenge, but it's a really good one too.  So basically, your deck is the equivalent of Uno Skip Turn. Bite your tongue, sir. It's more like forcing them into a position when their entire hand is yellow, all their drawing is yellow, and I'm the guy who keeps putting down draw plus fours and calling green. As a 21-year-old autistic male, I spent the first decade or so of my life being self-centered, apathetic, and lacking social skills. That all changed when I got to high school. I met two boys in my digital class, John and Dave, who seemed to tolerate me. They were funny, and they found me funny too. Through them, I became friends with a guy in my form class, Steve, and was quickly accepted into their group. This helped me grow and learn how to talk to people properly. However, looking back, year 10 was a bit rocky. Steve and John would mock my interests, like my love for Leonard Cohen's music. Eventually, going into year 11, I learned to brush it off as friendly banter. This is when Pete comes into the story. Pete was actually my first friend back in middle school. He'd spend weekends at my house, but I didn't realize at the time that he was using me. He'd hog my Xbox and other things I can't remember anymore. Once, my mom made us both an amazing glass of cocoa with whipped cream and marshmallows. I knew it was a special treat, but Pete wanted another one. When I asked my mom for it, she saw it right through Pete's intentions. Later, my mom checked on us and gently reminded Pete that I might want to turn on my own Xbox. The next day, Pete told me to go away, saying that nobody liked me. That was it for our friendship. He bullied me for the rest of middle school. Fast forward to year 11, and Pete was in my history class. He wanted to bury the hatchet, and we became inseparable. My parents, understandably, limited his visits to our house. Eventually, Pete introduced me to smoking the forbidden plant that makes teens feel naughty. In year 12, our group became a bunch of stoners. If we'd wasn't involved, we wouldn't hang out. Later in the year, Pete stole oxy from his granddad's cancer-stricken partner, just before she passed away. Despite claiming to love his granddad like a father, Pete showed a darker side. One night, after being kicked out of a friend's house, for being too loud, we sat in my car, high on oxys and weed. I played some of my favorite songs for Pete, ranging from dire straits to tool. At that point, I'd been playing guitar for two years, and Pete decided we should make music together. His plan was to use my instrumental skills and combine them with his non-existent rap production skills, aiming for fame. We moved in with his granddad the following year. Pete said he wanted to learn bass guitar and talked about it for months. I got a six-string Ibanez bass for Christmas, but he never touched it. Then, he shifted his focus to the keyboard, which I bought, but the same thing happened. After his granddad passed away, I moved back in with my parents. By that time, Pete had changed me so much that my relationship with them was strained. He even convinced me to sell some of their belongings for his own gain. From 2020 to 2021, not much happened. We both went from job to job, trying to save up for our own place to make our music plan work. We also spent thousands on professional recording equipment we didn't know how to use. In 2022, Pete was living with John's parents and working as a healthcare assistant when I met a woman. Pete tried to convince me not to see her, but I did anyway. For the first month, I drove two hours up north to visit her, and it was worth it. We became a couple after just three weeks. Taking a risk, my girlfriend moved in with me at my parents' house after just a month of dating. They were initially hard on us, likely due to their experience with Pete, but they quickly warmed up to her. Soon, we started searching for a house, sharing potential options with Pete. However, he always found something wrong with them. It didn't take long for my girlfriend to grow tired of Pete's negativity, and we decided it was better to move in on our own. A few weeks later, I finally summoned the courage to tell Pete about our decision, bracing myself for the eruption of Mount Pete. Predictably, he blew up like a firecracker, accusing me of sabotaging our grand music plans. We didn't speak for a month after that. After that outburst, we didn't speak for a month.  He quickly texted me, pleading to talk things out and not wanting to lose our friendship. But when I explained my reasons for blocking him, his attitude changed instantly. He went from wanting to mend our friendship to saying it was a good idea that we weren't friends anymore, blaming both of us for our past actions. In the end, he made it easy for me. He blocked my number, my Instagram, and even my Spotify account. Surprisingly, Pete left one platform unblocked, Discord. From that point on, the only person from the group I still saw was Dave, who seemed to have taken on the role of Pete's emotional spokesperson. He didn't hesitate to share how deeply wounded Pete's fragile feelings were. After Dave neglected to pay back the $110 he owed us, even after multiple reminders, my girlfriend and I decided to cut ties with him. We enjoyed four months of blissful silence. But then, Pete sent a message to the Discord that, if he had a shred of self-awareness, he'd probably regret for the rest of his life. Someone shared a video of a woman chugging canola oil straight from the bottle, and Pete chimed in with a cheeky, POV, OP's misses.  So, to say I was seeing red would be an understatement. Now, there's one detail I've left out of this story for good reason. You see, Pete had a habit of sending photos and videos of one of his clients to our Snapchat group. Now, that alone could have cost him his job. But wait, it gets worse. The client in question is disabled, both physically and mentally, and completely non-verbal. Pete, behaving like a clueless ape, would send photos of the client on the toilet and videos of him blowing vape smoke in the client's face, basically documenting his elder mistreatment. I saved the videos but didn't do anything because I was afraid of Pete's reaction. But enough was enough. I emailed his workplace and sent them everything. I showed the authorities, too. Pete was fired on the spot. No pay, nothing. He tried to flee to his dad's house three hours away, but the dimwit forgot that I'd met his dad and had been there before. So, I checked my Google Maps timeline and gave the authorities the information they needed. A week later, Pete was back at John's parents' house, where his car has remained ever since. God knows what he has told them for them to let him keep living there. Out of the 11 people in that group chat, only one still has me added. Steve messaged me on New Year's Day, saying, I just sent him a shrugging shoulder emoji. After a few more aggressive messages from him, I asked, what has Pete even told you guys? I haven't received a response. But here I am, almost a year with the love of my life, in our own place, and enjoying a steady dual income. We visit my parents every week. Meanwhile, Pete's still jobless, John's being cheated on by his girlfriend, who he refuses to leave, and Dave's gone from welding apprentice to supermarket shelf-stacker.  Well, folks, that puts the cherry on top of this deliciously devilish revenge Sunday. Did one of the revenge stories of comeuppance, tickle your funny bone, or did it make you shiver in sympathy? Spill your tea, because I'd love to hear from you. Feel free to share your own story on bullying in the comments below. While these stories of revenge may be entertaining, they're best served with a side of compassion and empathy, especially in your personal life. Remember, if you or someone you know is dealing with a bully, it's important to reach out for help. We're all about spreading love and laughter here, not perpetuating a cycle of negativity. Thank you for watching, my loyal viewer. I do this for you. Have a good one, and I see you in the next.


All right everyone, in this video I want to explain you quickly the difference between a pod and a deployment and for this I'm going to use Doom, the game, yes Doom because I've got a really special version of Doom which can listen to Kubernetes namespace and each time that the pod is created in this namespace there will be a monster in the game, okay? So let's create a pod here, a really simple pod and let me go to the game and you can see that the pod has been created and I should have a pod, a monster appearing here in the game. Where is the monster? There he is! Oh, there is my pod and let me try to kill this pod, he's trying to catch me and he's catching me. Let me kill it. I killed the pod, okay? Oh, he's resisting a bit but I killed him, okay? And you can see here terminating, oh, as long it is terminating the pod comes back, okay? Now he's really terminated, he should not come back and you can see here, well, I'm almost dead but no more pods and there's no more pods because we don't have a deployment behind it. So once the pod is killed, it's killed. If we want to make sure that our cluster maintain a count, a number of pods that we want, we need to create a deployment. So let's create a deployment. Let me check here and let me go for a deployment, there we go, a deployment. There is my deployment, okay? With one replica for now and let's create this and let me go back to the game and we should have a new pod appearing and where is he, where is he, he's there, okay? Let me try to kill it, he's far away, yeah, I killed it. But as soon as I'm killing it, a new one is creating. You can see that here just above me and there he is, whoa, whoa, whoa, whoa, okay? And that is because a deployment makes sure I have always the correct number of pods, okay?   So that was a funny way to explain you the difference between a pod and a deployment. You should never create a pod yourself, you should always use a deployment, okay? If you want to know more about all this great stuff that you can do with Kubernetes, be sure to visit our tutorial. It's really easy to go there, it's dn.desk.cube tutorial, you will find a ton of material, everything is explained, all the comments are explained and that's it, see you for our next video, bye, bye.


So, warm welcome to the 37th lecture on the subject of wavelets and multirate digital signal processing. Recall that in the previous lecture, we had discussed one way to analyze a general system with analysis and synthesis filters namely the approach of polyphase decomposition. Essentially, polyphase decomposition is a time domain approach where we recognize that all sequences in question whether the input sequence, the output sequence, the filter impulse responses could be thought of as comprising of as many sub sequences as the number by which the sequence is decimated and interpolated that is the down sampling and the up sampling factor. So, for example, if we have down sampling and up sampling by a factor of 2, we think of the odd and the even numbered points on all the sequences in question. The input sequence, the output sequence and the filter impulse response sequences. Based on this decomposition, we identify the relation between the output polyphase components as we call them and the input polyphase components through the filter polyphase components. So, essentially the polyphase approach which we built up in great detail in the previous lecture was a recognition of the relationship between the input polyphase components and the output polyphase components. Naturally, this is difficult to do purely in time and therefore, one needs to go to a transformed domain. What we have done was to identify this relationship essentially in the z domain. Further, we had noted that the condition for perfect reconstruction amounts to a condition on the product of the polyphase matrices corresponding to the analysis side and the synthesis side. So, when we look at the product matrix and if we wish that the output and the input polyphase components essentially replicate one another, we need to put a condition on the entries and I shall before I proceed to discuss the other approach today complete that discussion by putting the condition the requirement down explicitly. So, in the lecture today, we intend to look at the other approach namely the modulation analysis which we shall illustrate using a 3 band filter bank, but before that as I said we shall complete the discussion on the polyphase approach by writing down explicitly the requirement on the product matrix. Further, we shall in the later part of this lecture begin a discussion on applications of time frequency analysis of wavelengths of filter banks and so on and involved in these applications are actually several students who have taken the course for credit in the current semester. I shall put before the audience today some of these students who have investigated some applications in depth and done a very good job, we shall only look at a very brief introduction to their applications today and discuss them in depth in a subsequent lecture. So, with that perspective on the lecture today, let us begin to complete the first part of the discussion namely the final step in the polyphase approach. Now, recall that we had the output polyphase vector of order m which was a product of two matrices, the synthesis polyphase matrix and the analysis polyphase matrix and here we had the input polyphase vector, all these were order m, m here is the factor of down sampling and up sampling. Now, we could look at the product of these two matrices here. So, when we take the product of the synthesis polyphase matrix and the analysis polyphase matrix, we get a composite matrix square in nature and of size equal to the input of that matter the output polyphase vector of order m. So, it is very easy to see that the product of the synthesis and analysis polyphase matrices of order m is a square matrix. Size m cross m and the question that we are trying to answer is what should this square matrix be for perfect reconstruction. Now, the answer is very easy after all what does perfect reconstruction mean? It means that the output must be a delayed possibly delayed and a scaled version of the input. In other words, for perfect reconstruction we require y z the z domain is some constant times z raise to the minus t times x z and all that we need to do is to look at the relationship between the polyphase components on either side. So, if we decompose y z and x z, y z in the form summation k going from 0 to m minus 1, z raise the power z raise the power z raise to the power minus k y k m z raise to the m and similarly for x, we can now establish a relation term by term.  Now, all that we need to do is to take this z raise to the minus d inside and combine it with z raise to the power minus k. So, we have that becomes c 0 summation k going from 0 to m minus 1 z raise the power minus d plus k x k m z raise to the m and now all that we need to do is to separate d plus k. So, you see d is fixed for all k, if you look at this d plus k essentially carries out a rearrangement of the poly phase components. So, what it does you know let me take an example. Suppose m is equal to 2 let us write down to fix our ideas. Suppose m for variety instead of 2 let us take it to be equal to 3 and let us take d to be equal to 5. So, let us make a table k can of course, take the values 0 1 and 2. So, k plus d will take the values 5 6 and 7 and 5 is clearly equivalent to 2 6 is equivalent to 0 and 7 is equivalent to 1 modulo 3. Therefore, in this specific example where m is equal to 3 and d is equal to 5 the effect is to take the 0 th component of the 0 th poly phase component of order 3 of the input and map it to the 2 th number 2 poly phase component of the output. The 1 number poly phase component of the input get maps gets mapped to the 0 number poly phase component of the output and number 2 gets mapped to number 1. Essentially what we have is a cyclic rearrangement of the poly phase components and therefore, if we look at the product matrix what we require is that every row and every column must have only one non zero entry that non zero entry must be identical for each of the rows of that matter each of the columns. In other words, if you take every row and if you take every column there is exactly one non zero entry that entry is identical. It is same entry repeated the constant factor in each of these entries is c 0 and of course, the additional delay or the additional shift that we have depends on d. For example, in this case where d was equal to 5 the additional shift you know there will be there will be a factor of z raised to power minus 3 coming in. So, each of the poly phase components in addition to being rearranged in this way is multiplied by z raised to power minus 3 on the up sampled scale and if we replace z raised to power of m by z it is equivalent to multiplication by z inverse. So, this is the summary of the relationship between the input and the output poly phase components. Let us write it down explicitly. For perfect reconstruction the synthesis matrix times the analysis of the poly phase synthesis matrix poly phase must be of the following form. Each row and column has exactly one entry of the form c 0 z raised to power minus l. l essentially comes from d it depends on d. For example, with d equal to 5 and m equal to 3 and m equal to 3 is equal to 3 and poly phase vectors and matrices written in z cubed. So, we have the flexibility of writing the poly phase matrices in z cubed or just in z. If we write them in z cubed then l is equal to 3. If written in z then l is equal to 1. Now of course, this was meant to be illustrative. So, I leave it as an exercise for the student to work out a few more such examples. And in fact, at this point I shall raise a question, but not answer it immediately. And the question is if we have not obtained perfect reconstruction, but if the analysis synthesis system together becomes a linear shift invariant system. That means, one can equivalently treat the output as being acted upon rather the output as the result of the input being acted upon by a linear shift invariant system with a certain transfer function. What can we say about the entries of this product matrix when this linear shift invariance is present in the overall analysis synthesis structure? Can we attribute a certain structure to this product matrix? As I said I only raise the question at this point, but do not answer it right away. We leave it for reflection and possible answering at a later stage. Anyway with that discussion on the polyphase approach, let us now take the second approach that we had mentioned the last time namely the modulation approach. Now as I said the polyphase approach is essentially a time domain approach. The modulation approach is as we will see essentially a frequency domain approach if we like to call it that way. And the modulation approach essentially proceeds as follows. We look at one branch, so let us say the l th branch small l. We have the analysis filter h l z a down sampler by a factor of m and up sampler by a factor of m followed by a synthesis filter g l z and we wish to establish the relation across this. So, in other words all these branches with difference synthesis filters g l z are going to come together in summation to form y z. So, we could call this y l z and we shall write an expression for y l z in terms of x z here using a modulation paradigm. Now the idea behind the modulation paradigm is to look at the combination of these two operations here down sampling by m and up sampling by m as we noted even before is essentially multiplication by a periodic sequence. Let us call it as p m n, p m n is 1 whenever n is a multiple of m and 0 else. Now in the modulation approach we think of the process of down sampling followed by up sampling as modulation by a sequence and that sequence is again broken into its component sequences each of which is an exponential. The reason why we choose the exponential is because it is easy to analyze what happens in the z domain when we multiply by an exponential and how can we express such a sequence in terms of exponentials? Well we take recourse to the idea of the discrete Fourier transform. So, we fix our attention on one period of this periodic sequence. We take the discrete Fourier transform of this period that tells us the components of one period along so to speak different modulators. Let me do that what I am saying is consider one period p m n restricted to 0 to m minus 1 and take its t f t that is easy to calculate. The d f t is capital P or let us write p tilde for convenience p tilde m as a function of k if you like essentially a dot product of one period of the sequence with the exponentials. W m here being defined as e raised to the power j 2 pi by m. Now we know how to reconstruct p m n from its discrete Fourier transform but before that let us evaluate this expression. This expression is very easy to evaluate. It has only one non-zero term in the summation and that is p m 0. So, in fact p m tilde k simply becomes 1 for k going from 0 to m minus 1 and therefore, reconstruction is very easy p m n in fact not just in the region between 0 and m minus 1 but everywhere is 1 by m summation k going from 0 to m minus 1 1 times W m raised to the power n k for all n. Essentially we have done an inverse t f t here. Having said this now it is very easy to see what we are doing to the input sequence. You see if we look at this branch once again if we take this branch and look at it carefully once again we know what has happened here. Essentially there is a modulation of the sequence here by a periodic sequence. We can write down the z transform of the sequence here with great ease and we can also write down the z transform of the sequence here by using the principle of modulation. So, let us write down at each point. We have x z there after being processed by H L z we have x z times H L z. Now, this is modulated by 1 by m summation k going from 0 to m minus 1 W m raised to the power k m and recall that when we modulate a sequence by alpha 1 by m raised to the power of n z is replaced by z alpha inverse in the z transform. If we use this property repeatedly and note that the z transform is a linear operator then we have x z H L z there after down sampling and up sampling. What we obtain is that is 1 by m summation k going from 0 to m minus 1 x z W m raised to the minus k times H L z W m raised to the power minus k. So, therefore, we have m modulates of the input being acted upon by corresponding m modulates of the analysis filter and now we know what happens when this is subjected to g z that is very easy. So, what we have here essentially is y L z the L th branch carries on it g L z times summation k going from 0 to m minus 1 x z minus 1 x z W m raised to the power minus k times H L z W m raised to the power minus k. Now, we could write this in matrix vector form. So, we could write a vector of y L here and we could write down what is called a modulation matrix and a modulation vector. The modulation vector here of course, it is the input which creates a modulation vector and the modulation vector is going to be of size m cross 1. The size of this vector here of y L is going to be as many as the number of branches here and of course, what is then going to be done is to add up all of these to obtain the output. Let us write down a typical row of the modulation matrix the L th row of the modulation matrix is essentially g L times g L z times H L z to the power z into omega W m to the power of 0 H L z W m to the power minus 1 and so on up to H L z W m to the power minus m minus 1. So, essentially the modulation vector here is modulates of the analysis filter multiplied by the synthesis filter. Now, it is very easy to put down a condition for perfect reconstruction or at least shift invariant reconstruction. So, for perfect reconstruction we first want alias cancellation and alias cancellation essentially means no contribution from x z W m raise the power minus k for k not equal to 0. The only contribution we desire is for the case where k is equal to 0 and if we go back to the structure of modulation here. So, if we look at the structure once again what we are asking for is that the first element of this vector must encounter a corresponding non possibly non 0 column, but all the other elements of this vector must encounter 0 columns here and therefore, what we are asking for essentially is that the first first column of the modulation matrix is the only non 0 column. Well, the other way of looking at it is well this is a very stringent requirement. So, this is sufficient, but of course as we can see it is not necessary. The slightly more relaxed condition would be in summing up all the y l z we would like the other terms to be cancelled. So, what we are saying really is if we take the sums of all the after all what we are going to do is to take the sums of the columns here in the modulation matrix when reconstructing the output from the input. In these sums we are going to involve essentially terms x z x z W m to the power 1 2 3 and up to m minus 1 the sums corresponding to the terms other than k equal to 0 must be 0. So, although 0 columns is a good thing to have that would be possible only in the ideal case and therefore, we would in general ask not for 0 columns, but columns with sum to 0. So, a more general condition is sums of columns in the modulation matrix equal to 0 for all k not equal to 0. Now, before we conclude the discussion on this approach of modulation to fix our ideas let us consider the concrete case where we have a 3 channel filter bank with m equal to 3. Let us write down the modulation matrix explicitly. So, the modulation matrix is going to have the form well you know it is easy to write down as a diagonal matrix times another matrix H 0 z H 0 z W 3 H 0 z or if you like W 3 inverse and H 0 z W 3 to the power minus 2. Similarly, H 1 H 2 in the column 2nd and column 3rd here what we would then desire of course, G 0 z multiplies each of the the first row G 1 z the second row and G 2 z the third row. So, what we would ask for is that G 0 z or rather G L z times H L z raise the power W 3 to the power minus k summed for L going from 0 to 2 must be 0 for k equal to 1 and 2. So, essentially what we are asking for is that these columns would sum to 0 here in the product. Now of course, we can actually carry out an exercise to write down the ideal filters for the 3 band filter bank and build the idea from there and I encourage the class to work out this exercise. Consider the ideal 3 band 3 channel filter bank where the analysis and synthesis filters are each triple band filters. So, the low pass filter there is an ideal filter with pass band from 0 to pi by 3, the middle filter is a band pass filter with pass band from pi by 3 to 2 pi by 3 and the last one is an ideal high pass filter with pass band from 2 pi by 3 to pi and work out the modulation terms explicitly to see how they come together and cancel Elias terms. As I said we have been doing a lot of concepts all this while and my objective in a couple of the subsequent lectures is to introduce some applications particularly applications that have been investigated by the class that was taught this subject this semester. I have invited to this lecture some of the groups of students who have done an excellent job in their application assignments specifically we have two groups that will present themselves today very briefly and in greater detail in a subsequent lecture. Today's will be a trailer so to speak just an introduction to their applications. The two applications that we are going to look at is first an application on face recognition and another application on data basis or data mining without taking the thunder away from the people who are going to introduce the application today. Let me now hand over to the students who are going to briefly introduce the application today and discuss in depth later. Thank you. As a part of course work we the students of this course have looked at some of the applications that include domains like biomedical engineering, image processing, audio signal processing, a few applications in mathematics and a few applications in data mining. In fact the application today that I am going to present is from image processing. My name is Ronak Shah and the topic that we are going to cover is face recognition through wave packet analysis. So, there are two keywords here one is face recognition and the other is wave packet analysis. Now why face recognition? We can look this particular keyword as biometric authentication problem but the problem is face recognition incorporates change in signals so faces can be changed abruptly. So, this will be a difficulty if we go for biometric authentication whereas some other signals like retina and fingerprint they cannot be changed or morphed so easily. So, face recognition as that case has limited application in biometric authentication. So, where do we require it? We require face recognition in some part as activity analysis. Let us say we are looking at a surveillance application in which we have to man some particular region in which no persons are allowed. In that case if we go for face detection and recognition we can get a very good hand over the particular region. So, that we can say that somebody entered at this particular time and what he was doing. So, we can basically go for activity tracking as well as abnormality detection. So, what that person was doing is also applicable in that case. What we are looking at is face detection as well as recognition whereas these things are always coupled face detection and recognition approaches are always different like face detection when we go for we are looking for those features which are common to all faces whereas in case of face recognition we are looking at features which are different across faces. So, this problem can be decoupled in that sense and we are only going to look at face recognition here. So, here it is assumed that some region of some region of image that contains face is given to us and we are only going to do face recognition. As I said there are two keywords one is face recognition and another is wave packet analysis. Now why wavelet based approach and not other approach? If we look at typical face image it contains nose, eyes, mouth etcetera and these are in focus when we look at different scales in different subspaces because they contain different frequencies as well as spatial regions. So, we need to go for decorrelation in spatial as well as in frequency domain. So, this is the ideal application this is the signal where we need to look into time as well as frequency localization. So, that is where we are looking into wavelet domain. Now, wavelet gives better representation in terms of time and frequency that is fine that will be required for classification. So, why wavelet packet analysis? Now as we know if you pick features if these features are decorrelated as we get in wavelets but if they are more rich in terms of information we can classify it better and that is what we do with wavelet packet analysis. With wavelet packet analysis we are not only decomposing low frequency bands, but we are also decomposing the bands which are at high frequencies and this gives richer representation for the face image. So, there are two things here we are decorrelating in space as well as in frequency domain and we are getting better representation. So, what we need to do is given an image we need to decompose by wavelet wave packet analysis and then we can represent it by features and these features are well decorrelated. So, we can do a very good classification. The only problem that stands now is with the dimensionality see if we decompose this image into let us say multiple sub bands let us say some 10 or 15 sub bands the data that we have for classification is immense and as we know like the curse of dimensionality that requires a lot of images for classification and that we cannot do. So, one thing we can do is we can go for moments based approach and we can take only first and second movement mean and variance with features and then we can classify that we can do. So, this is just a showcase I am going to show a few slides in which there are some results of decomposition and some basic retrieval we are going to see detail approach in subsequent lectures. So, this is the basic wave packet analysis we can see. So, given a face image we can decompose it into approximation and detail subspaces how this is done and which filters are utilized that we are going to see in detail subsequent lectures. So, this is level one decomposition in level 2 decomposition we can similarly decompose approximation as well as detail subspaces. So, we will get some 16 subspaces in which one will be approximation and some 15 will be detail subspaces. Now, we need to generate features for this as I said we are going to use mean and variance only for feature representation. Now, come to think of this when we utilize Euclidean distance we generally have features which are not mean and variance together because we need we are now looking towards PDFs probability density functions rather than individual values. So, we need a distance metric which takes care of mean as well as variance. So, normal Euclidean distance will not perform better in that case. So, we need to go for some other distance and that will be utilized later that I will talk about later in subsequent lectures. Now, I am going to show some of the decomposition results this is just for introduction. So, we can see given an original image like this Lena in the face image we can decompose into different bands here we can see this is the approximation sub image or other subspace. So, we can see some of the details very clearly and these are the like all other 15 are detail subspaces. So, they basically capture some high frequencies. Now, the problem with this original images if we go for approximation we cannot capture low frequency the DC because we need to take care of lighting condition as well. So, this approximation so, in that case we cannot utilize low and high frequencies as we traditionally use in wave packet analysis. So, what we are going to use will be again in subsequent lectures and I am going to show some of the results and I will conclude this showcase for this particular application we have used Yale database. So, given an image like this which has different expression like Yale image Yale database contains some 15 subjects and 11 different expressions and lighting conditions. So, if you get better results here like your algorithm must be robust in that case. So, given a query image like this we either need to retrieve images of the same class like this, but as we can see expressions are different all the when lighting conditions are also different or for other application we might go for given a single image where either only interested in let us say the class to which it belongs or we are interested in all the images. So, in later case we can go for activity analysis and first case we are going for recognition problem traditionally. So, this is what I am going to present in subsequent lecture in detail and with this I will conclude the showcase. Good morning the topic of our presentation for this application assignment is application of wavelet in data mining. I am Orko Choudhury and my other group member is Kunalsha. In today's world we need to deal with the huge amount of data for a lot of practical purposes and data mining is a subject better to say it is an ensemble of the methods or tools which we use to deal with huge amount of data efficiently for our own purposes. Now, this dealing with data involves two things one is storing it with the help of an efficient data structure and second is a retrieval of data from the data structure as for our own purpose. Now, for this purpose when we have to store and retrieve the data the user basically interacts with the data structure by the help of some queries and responses. Now, in practice when we have a large amount of time series data the queries that are generally encountered are not point queries rather they are the queries which spends over some larger duration of time such as I am if I am having a data structure which says that I am having the stock prices the daily stock prices of a company over a particular period of time then the queries which generally we encounter are something like this on which months the stock prices had a rising trend or on which weeks the stock prices suddenly had a deep dip. So, in order to get this data we need to do some post processing on the raw data and we get the output of this queries this way we interact with the data structure and we get the output. Now, here we can think that now in this case of this application assignment we can think that why we are correlating wavelet with this type of situations. Now, we all know that wavelet transform on a signal gives us the information at various levels of trends at better to say at various levels of abstraction and with the various translates and various scales. Now, if you practically look at a data structure where the raw data can be thought of as a sequence or signal better to say then we can think that we are also interested in various translates and scales of the signal in particular if we say our daily stock price data as a sequence then depending on our queries we can say that we are interested in various translates on the data such as we are interested in a data two months back or we are interested in a data six months back. So, this two months six months these are different translates at the same time we can also explain it in this way that we are interested in a data at different scales such as we are interested in a in a weekly data around two months back. So, in that case that two months becomes a translate and the week becomes a scale similarly we are interested in a monthly data two years back. So, in that case that monthly data becomes the scale and the two years back that two years becomes the translation parameter. So, based on this analogy we found that wavelet can be used very efficiently in this situation to deal with this type of analysis and in this case if we use wavelet then we need a very little post processing to analyze this type of data because whatever data mining technique we use our main aim is directed on two things. The first one is that we need a least memory crunchy data structure and the second one is we need the least amount of post processing that is the post processing complexity becomes very less. So, if we use wavelet in this case our post processing complexity reduces drastically because if we have to do the response if we have to answer to the query based on only the raw data then we have to do a lot of amount of post processing. Now, let us have a deeper look in what we have exactly done in our application assignment we have basically done the trend and surprise analysis of a time series data. We have done the trend and surprise analysis of a time series data at various levels of abstraction and for this purpose we have used a particular data structure which is called a trend and surprise abstraction tree in acronym it is called a TSI tree and it is it looks like something like this at this x node it is something like a tree and the root node and the top at the top level this root node which is the x node it is the original sequence itself and now all the subsequent nodes this one a 1 d 1 a 2 d 2 these nodes are obtained by discrete wavelet transform of its parent node and in this way we constructed tree which is called a TSI tree and as we go down this tree by taking the discrete wavelet transform at this level again we take the d w t on a and we get this a 2 and d 2 again we take d w t on a 2 we get a 3 d 3 and so on we can proceed in this way the number of levels as what we want now when we go down each level it is something like we are increasing the all level of abstraction by 1 level each and whenever we need a trend or surprise at any level say at this level. So, first we need to extract out this node here and each node corresponds to a 1 particular sequence. So, first we need to extract out this node and from this node with some further post processing we have to find the trend information corresponding to this level the almost similar to apply to the surprise information also if we have to extract out the surprise information at this abstraction level. So, we need to first figure out this d 2 node and from d 2 node we have to do the post processing to get our surprise extraction. Now the next part of our job is that we have to implement this thing in a memory efficient manner. Now for this purpose it is important to look into that matter that at the first appearance it may appear that we need to store this whole variability into our memory for our operation. But it is a little deeper look we will say that we do not need all the nodes to store in the memory if we store only these leaf nodes we can generate any of the intermediate nodes from which we can start our calculation and so only this leaf nodes are enough to get any of the intermediate nodes. So, we just need to store only the leaf nodes and for further on we have compared to more algorithms which are known as node dropping and coefficient dropping which talks about further compressing the leaf node information. So, that to get a more memory efficient implementation of this method. So, this is the whole outline of our work that which we have done and we will elaborate it in further details in the subsequent presentation. Thank you. So, we saw two very interesting introductions to applications by Ronak Shah and Orko Chaudhary. Of course, both of these students and their groups would present the application, the results, the concepts in much greater depth in a subsequent lecture. What we intend to do today was to raise the curiosity of the student to want to understand these applications better and we shall satisfy that curiosity in a subsequent lecture. Thank you.