Why the graphics card matters
A processor (CPU) is like a few brilliant specialists: fast at complicated tasks, one after another. A graphics card (GPU) is like thousands of workers doing simple sums at the same time. Video frames and neural networks are both mostly simple sums repeated millions of times — so they run many times faster on a GPU.
WebGPU: the graphics card, for web pages
Browsers have long let pages draw with the GPU (through WebGL), which is how effects and filters run smoothly. WebGPU is its modern successor, and crucially it lets pages compute on the GPU — exactly what AI models need.
In VDOAPP the difference is most visible in captions. The largest speech model, Whisper large-v3-turbo, is only offered when WebGPU is available, because on a processor alone it would be painfully slow. With WebGPU it can transcribe faster than the audio plays on a recent laptop.
WebAssembly: near-native speed on the processor
WebAssembly (Wasm) lets code written in languages like C++ or Rust run in the browser at close to the speed of a normal installed program. It's the fallback when WebGPU isn't available, and it's ideal for small models that run constantly — such as noise suppression, which processes audio in tiny 10-millisecond chunks.
WebCodecs: direct access to video
Your phone and computer contain dedicated hardware for decoding and encoding video (H.264, HEVC and others). WebCodecs gives web pages direct, frame-by-frame access to it. That enables:
- Frame-perfect export faster than real time, instead of recording the screen while the video plays.
- Reversing clips by decoding groups of frames and re-encoding them backwards.
- Preview copies of 4K footage for smooth editing.
Does my browser support it?
| Browser | WebGPU | WebAssembly | WebCodecs |
|---|---|---|---|
| Chrome / Edge (desktop) | Yes, on most recent devices | Yes | Yes |
| Chrome (Android) | On many recent phones | Yes | Yes |
| Safari (Mac, iPhone, iPad) | In recent versions | Yes | Yes (recent versions) |
| Firefox | Arriving platform by platform | Yes | In recent versions |
Support is changing quickly, so the simplest test is practical: open VDOAPP's AI tab and look at the Accuracy menu under Auto captions. If "Max" is listed, WebGPU is working.
Getting the best speed
- Keep your browser updated — each release improves these features.
- Plug in your laptop. On battery, many laptops use the slower integrated GPU or throttle it.
- Close heavy tabs when captioning long videos; memory matters as much as speed.
- Be patient the first time. The first run of a model includes downloading it and preparing it for your specific GPU. After that it starts quickly.