瞭解 Free AI Video Upscaler 如何使用 WebGPU + WebCodecs，以零伺服器成本服務 25 萬月活躍使用者

import WebSR from "https://esm.sh/@websr/websr@0.0.15";

const gpu = await WebSR.initWebGPU();
const canvas = document.getElementById("canvas");

const websr = new WebSR({
  network_name: "anime4k/cnn-2x-l",
  weights: await (
    await fetch("https://katana.video/files/cnn-2x-lg-2d-animation.json")
  ).json(),
  gpu,
  canvas,
});

const img = document.getElementById("source");
const bitmap = await createImageBitmap(img);

await websr.render(bitmap);

import {
  SimpleDemuxer,
  VideoDecodeStream,
  VideoProcessStream,
  VideoEncodeStream,
  SimpleMuxer,
} from "https://esm.sh/webcodecs-utils";

import WebSR from "https://esm.sh/@websr/websr@0.0.15";

// Fetch demo video
const arrayBuffer = await (
  await fetch("https://katana.video/files/hero-small.mp4")
).arrayBuffer();
const videoFile = new File([arrayBuffer], "hero-small.mp4", {
  type: "video/mp4",
});

// Initialize WebGPU and WebSR
const gpu = await WebSR.initWebGPU();
const weights = await (
  await fetch("https://katana.video/files/cnn-2x-lg-2d-animation.json")
).json();
const websr = new WebSR({
  network_name: "anime4k/cnn-2x-l",
  weights,
  gpu,
  canvas,
});

// Set up demuxer
const demuxer = new SimpleDemuxer(videoFile);
await demuxer.load();
const decoderConfig = await demuxer.getVideoDecoderConfig();

const encoderConfig = {
  codec: "avc1.4d0034", // https://webcodecsfundamentals.org/codecs/avc1.4d0034.html
  width: 640,
  height: 360,
  bitrate: 1000000,
  framerate: 30,
};

// Set up muxer
const muxer = new SimpleMuxer({ video: "avc" });

// Build the upscaling pipeline
await demuxer
  .videoStream()
  .pipeThrough(new VideoDecodeStream(decoderConfig))
  .pipeThrough(
    new VideoProcessStream(async (frame) => {
      // AI upscale with WebSR
      await websr.render(frame);
      const upscaledFrame = new VideoFrame(canvas, {
        timestamp: frame.timestamp,
        duration: frame.duration,
      });

      return upscaledFrame;
    }),
  )
  .pipeThrough(new VideoEncodeStream(encoderConfig))
  .pipeTo(muxer.videoSink());

// Get output
const blob = await muxer.finalize();