motion-canvas VS ccapture.js

Hey HN! We’re building Revideo (https://github.com/redotvideo/revideo), an open source toolkit that lets you programmatically create and export videos with the animation library Motion Canvas (https://github.com/motion-canvas/motion-canvas). This is useful whenever you want to build apps that automate certain video tasks, which is increasingly possible using AI tools - for instance, one of our first users is building an app that turns code documentation into video tutorials.

Revideo extends Motion Canvas with features that are essential for creating video, such as the ability to export audio tracks, a nodejs package for headless, parameterized & much faster rendering, and audio components that make audio editing and syncing easier. While Motion Canvas aims to be a standalone editor [1], we want to build a set of libraries that lets developers integrate video editing functionality into their apps. Our goal is to provide an open-source alternative to Remotion (https://github.com/remotion-dev/remotion).

At the start of this year, we explored a bunch of product ideas in the space of AI-based video creation. For example, we’ve built apps that automatically create educational short videos and have experimented with automatically A/B testing and personalizing video ads.

While building these products, we were frustrated with the video editing frameworks we used: Moviepy (https://github.com/Zulko/moviepy), which we relied on initially, doesn’t offer a way to preview your videos, so we’d often have to wait minutes for a video to render to test our code changes. Remotion (https://github.com/remotion-dev/remotion), which we switched to later, is really good, but we didn’t want to rely on it as it is not open source (source-available only). That’s why we decided to build Revideo.

We’d already been following Motion Canvas for some time and really liked using it, so we thought that extending it would get us to something useful much faster than building an animation library from scratch. Initially, we tried to build our features as Motion Canvas plugins, but this did not provide enough flexibility to achieve the desired functionality. Additionally, video-specific features (such as audio support) were generally considered out of scope by the Motion Canvas maintainers, which is why we ultimately ended up creating a fork. We’re unsure if this is the right way to go in the long term, and would prefer to find a way to build Revideo without diverging from Motion Canvas too much - if you have suggestions on how to solve this, we’d love your input.

Compared to Remotion, which builds on top of React, Motion Canvas uses the HTML Canvas API and makes you define animation flows with generator functions. Its API is more “procedural”, as it makes you define the things that happen in your animation as a sequence of yields, whereas Remotion gives you a frame number and lets you declare how your video should look like at that frame.

Our current focus is improving the open source project. In the long term, we want to make money by building a rendering service for developers building apps with Revideo. Such a service would offer a pretty similar deployment experience to Vercel, but instead of web apps, we let developers deploy Revideo projects and expose a rendering endpoint for them. Letting us manage the infrastructure will allow us to offer much faster rendering, as we can massively parallelize rendering jobs on our servers (e.g. spinning up 100 headless browsers that render 100 frames each to render a video with 10,000 frames).

We’d love to hear your feedback and suggestions! You can find our repo at https://github.com/redotvideo/revideo, We’ve also released an example video editing app at https://github.com/redotvideo/revideo-saas-template. Thank you!

[1] “Motion Canvas is not a normal npm package. It's a standalone tool that happens to be distributed via npm.” - https://github.com/orgs/motion-canvas/discussions/1015

I'm using https://motioncanvas.io/, but it's a little bit tough to learn

Coming to motion design, this rumour takes of due to the fact that there are programming libraries like Manim and Motion-Canvas which are actually used to generate animations from code. You can search 3Blue1Brown channel on youtube.

Personally I would look at codebased animation programs for something like this. Maybe possible with for example Motion Canvas - web github

You might also consider JavaScript to use ThreeJS or Motion Canvas.

Most of the credit goes to https://motioncanvas.io/ here 😉 But thanks anyway!

You can try to use motion Canvas its still new but amazing. Motion Canvas

I also tried to find a better recording method. Since I’m now using canvas, there are some solutions to recording that seemed quite elegant. For example, paper.js uses requestAnimationFrame to achieve its smooth animation. There are libraries like ccapture.js that hooks into the various methods like requestAnimationFrame and setInterval, allowing it to render each frame separately.

I actually spent a fair bit of time on this and eventually got something to work. Someone named "spite" made a great library called CCapture for doing this, but it needs to be updated and repackaged for ES6. Right now it is painful to integrate into your project, but it could be super-easy. You can help to encourage someone to fix the issues here.

Check out CCapture.

The image capture step uses ccapture to ensure that the playback frame is converted to an image. All frame images to webm video.

ccapture.js basically let's you write out frames from a threejs camera, which you then stitch together with ffmpeg.

I use ccapture, using the png option, which will spit out a tar with a png of each frame, and then I stitch them with ffmpeg.

This video is 1800 frames (30 FPS * 60s)... a browser trying to save 1800 individual frames would lock up and die. Ccapture.js hooks into the browser's rendering code and captures the frames as a 'blob' - a binary object that is often used for streaming video - and then wraps them up into one single download.

p5.js runs the sketch, ccapture.js captures all of the frames (1800 in this video), and ffmpeg combines the frames into an MP4.

I use ccapture.js, which captures the frames as a blob in real-time then exports it as a .tar file full of jpgs when the sketch is finished (with 'finished' defined as reaching 1800 frames, in this case). This is a lot better than having the browser try to save 1800 jpgs the usual way.