convert all images to webp

compress-all.js

@@ -0,0 +1,90 @@
+import fs from "node:fs/promises";
+import path from "node:path";
+import sharp from "sharp";
+
+const SRC_DIR = path.resolve("docs/public"); // change if needed
+const OUT_DIR = path.resolve("docs/public/images"); // change if needed
+
+const MAX_W = 800;
+const MAX_H = 600;
+
+const FORMAT = "webp";
+const WEBP_QUALITY = 75; // tweak 60-85 if you want smaller/larger
+
+async function walk(dir) {
+  const entries = await fs.readdir(dir, { withFileTypes: true });
+  const files = [];
+  for (const e of entries) {
+    const p = path.join(dir, e.name);
+    if (e.isDirectory()) files.push(...(await walk(p)));
+    else files.push(p);
+  }
+  return files;
+}
+
+function isImage(file) {
+  return /\.(png|jpe?g|webp|avif)$/i.test(file);
+}
+
+async function ensureDir(p) {
+  await fs.mkdir(p, { recursive: true });
+}
+
+async function processOne(inPath, outPathBase) {
+  await ensureDir(path.dirname(outPathBase));
+
+  await sharp(inPath)
+    .rotate() // respects EXIF orientation
+    .resize({
+      width: MAX_W,
+      height: MAX_H,
+      fit: "inside", // preserve aspect, fit within box
+      withoutEnlargement: true, // don't upscale small images
+    })
+    .toFormat(FORMAT, {
+      quality: WEBP_QUALITY,
+      effort: 4,
+    })
+    .toFile(`${outPathBase}.${FORMAT}`);
+}
+
+async function main() {
+  const files = (await walk(SRC_DIR)).filter(isImage);
+  await ensureDir(OUT_DIR);
+
+  let done = 0;
+
+  for (const inPath of files) {
+    const rel = path.relative(SRC_DIR, inPath);
+
+    // strip original extension and write same relative path
+    const outBase = path
+      .join(OUT_DIR, rel)
+      .replace(/\.(png|jpe?g|webp|avif)$/i, "");
+
+    const outPath = `${outBase}.${FORMAT}`;
+
+    // simple cache: skip if output exists and is newer than input
+    try {
+      const [stIn, stOut] = await Promise.all([
+        fs.stat(inPath),
+        fs.stat(outPath),
+      ]);
+      if (stOut.mtimeMs >= stIn.mtimeMs) continue;
+    } catch {
+      // output missing -> process
+    }
+
+    await processOne(inPath, outBase);
+    done++;
+  }
+
+  console.log(
+    `Optimized ${done} image(s) to max ${MAX_W}x${MAX_H} (${FORMAT}).`,
+  );
+}
+
+main().catch((e) => {
+  console.error(e);
+  process.exit(1);
+});