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Please welcome.
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Yeah, that’s a tough job. It’s the last talk before the lunch break, and I’m going to try to keep it short.
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My name is Florian, and you can find me online. Unfortunately, you cannot find me on Facebook.
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This is my first time in Poland, and it’s been really awesome. The people here are super friendly. But the best thing that I’ve found so far is this.
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Pretty accurate! That’s all I can say about this.
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Now, I wanted to warn you about a few things. This isn’t really a soft talk, but it’s also not purely technical. As the title suggests, there’s going to be a lot of half-truths, experimentation, and guessing.
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Or maybe not guessing, but it’s not particularly the kind of thing that you would want to take home and use directly in your product. Also, there’s going to be a lot of CoffeeScript code, so I apologize if you’re not a fan. I prefer CoffeeScript over JavaScript.
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So, how did I come to this topic? I was watching a video of a talk by Aaron Patterson at Aloha RubyConf.
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He basically suggested that we should take better advantage of the browser, among other things. He worded it a bit provocatively, saying we should steal, lie, and cheat more.
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This means making better use of the resources we have, and that’s where the title and inspiration for this talk come from.
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We have just had two big releases, and this community is not very old, but Ruby is nearing 20 years and Rails is 10. We’ve been doing things in a very similar way for a long time.
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I’m not suggesting that we should completely change everything, but I would like to suggest that there might be some new things we could try, particularly those that involve the browser.
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I’d like to give you some ideas that you could try and think about to find ways to improve your applications.
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There’s a demo here, despite the common saying that you really shouldn’t do demos or live coding because they tend to go horribly wrong. I don't have the problem with the demo I’m going to make now because I know it’s probably going to fail. I’m at least 80% sure it will fail.
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But actually, it doesn’t matter; you’ll see in a second why.
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So, what I’m going to do is show you an application I’ve built. This is actually going to be quite difficult.
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I created a small application that is supposed to measure your heart rate in the browser. Let’s see how this goes.
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So, I placed my thumb on the camera, but this doesn’t actually fit. Sorry, everyone.
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This is seriously difficult.
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Alright, yes, good. So it failed.
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The reason I’m showing you this is that I can show you why it failed. The problem is that the data is too noisy, and I cannot detect the heart rate well enough.
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This is not actually the key point here; the point is that I was able to do this all in the browser. So, why did I attempt this?
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I came across an article from the book 'Exploring Everyday Things with R and Ruby' that spoke to me. I highly recommend reading it, as it beautifully describes a complex process in a simple manner.
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I come from a front-end background, and this really resonated with me because it addresses a very human problem involving hardware.
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I realized I actually have all the tools to accomplish this right in the browser, so why not? It turned out to be doable.
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Just to quickly explain the tools used, they require a good camera that can take a series of images, which you then read into your machine.
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The code described there would take over, but in the browser, I can accomplish everything in one go. I have direct access to the camera.
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I read a few frames using the camera and push them into a canvas. This setup is necessary, and I have the preview screen that you saw a moment ago.
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I have some methods to track whether recording is running, and the last line gives us access to the camera, which has been possible in some browsers for a while.
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This key piece made me want to try to work with the browser because I can perform everything seamlessly. While the developers who used Ruby and R would have to use an external camera and move files around, we can do it all in the browser.
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I have access to data in real-time, but I’ll describe the technical aspects of how it works, as it highlights an interesting point.
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You snap a few pictures, read them into a canvas, and process the data. Unfortunately, it’s quite bright here, and I might struggle to show you.
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So we read a couple of frames using the camera and push them into a canvas. This is the setup required.
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I have methods that keep track of whether recording has started or is currently running.
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This is significant because now I can access the camera in the browser.
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The browser can process pixels using requestAnimationFrame repeatedly. I also capture data of pixels for a defined duration.
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Each pixel is represented by RGBA values, and I mainly focus on retrieving the red value.
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This process allows me to determine how red a frame is and correlate it with heart rate.
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So why does this not work well? It’s mainly that the camera isn’t good enough, and lighting conditions can be problematic.
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Additionally, the algorithm detecting the peaks might be suboptimal, but injecting fake results works well in the browser.
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There’s so much more that can be accomplished in today’s browsers than we’re currently doing.
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You need to implement some shims to ensure broader compatibility across browsers.
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This piqued my interest. Although things didn’t work perfectly, I knew with enough time, I could make them work.
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I started considering how we build web applications right now. The computation generally happens on the server, while we focus on the UI.
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Could we shift some tasks to the client? It seems the browser can handle much more than we currently let it.
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I wrote a simple script to guess MD5 hashes to experiment with this in the browser.
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It’s a naive approach that provides insight when comparing performance with Ruby.
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Unfortunately, I found that the browser froze after generating four characters, which was disappointing.
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I was moments away from giving up, thinking that this talk might be futile, but re-evaluating helped.
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Now, I wonder what types of problems consume significant server resources.
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Typical web applications involve media processing, and solving these problems in the UI could work efficiently.
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For instance, I wondered if we could implement video scrubbing in the browser.
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I created a solution that effectively retrieves the desired thumbnails from a video.
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This all happens in the browser, meaning the user can access content without server delays.
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Thanks to new JavaScript APIs, we can access temporary object URLs for files, enhancing user experience.
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However, issues might arise if not all video formats are supported or JavaScript is disabled.
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I worked on an image annotation application using Dragonfly, which initially seemed practical.
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Despite this, I learned that handling multiple image sizes became burdensome without knowing the required sizes in advance.
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I addressed this by implementing client-side image processing techniques, leveraging the browser's capabilities.
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This enables a more responsive user interface, even if the uploaded image isn’t available on the server.
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However, the success of this approach depends on the user's experience being smooth with minimal delays.
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The potential implementation of this could involve creating a jQuery plugin to simplify the image resizing process.
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This would utilize the canvas object for cropping images directly within the browser.
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If we shift workloads to the browser, we might enhance responsiveness and overall user satisfaction.
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However, challenges with browser support are still a concern, especially around certain functionalities.
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Despite the difficulties, you’ve seen examples that stretch the boundaries of what’s possible in a browser.
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The heart rate measurement demo is an example; it required significant processing, which I handled using web workers.
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I found out that processing too many frames simultaneously can make the browser crash due to worker limitations.
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I wrote code to manage the number of active workers to avoid crashing the browser, creating a much-needed library.
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So, how do you use this library? You require it, create a new job set, and track completion through callbacks.
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This will take care of not exceeding a predetermined number of workers and simplify job management.
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The intention is to provide a cleaner API for defining your workers in the future.
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The current process for defining workers isn’t very user-friendly. The inline workers are a somewhat complex workaround.
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Organizing workers to handle simultaneous tasks leads to efficiencies in handling frame capture and processing.
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If we can achieve this, it opens the door to shifting workloads from the server, reducing resource strain.
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I believe that providing a persistent queue for jobs completed could improve user experience and allow execution after user closure.
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Although browser differences exist, we shouldn’t let that hold us back. There’s an opportunity to leverage browser capabilities.
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We need to refine our practices, incorporating these new possibilities in our applications.
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Embracing modern browser features can enhance user experience, offload work from servers, and meet evolving standards.
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This is the encouragement I leave you with.
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Thank you!
