feat: add docker pipeline and preview fixes

2026-05-06 12:59:50 +08:00
commit 9ba85b01f3
44 changed files with 13894 additions and 0 deletions
@@ -0,0 +1,76 @@
+export function buildThumbnailCandidateTimes(durationSeconds) {
+  const duration = Number(durationSeconds);
+  if (!Number.isFinite(duration) || duration <= 0) {
+    return [0.15];
+  }
+
+  const upperBound = Math.max(0.05, duration - 0.05);
+  const baseCandidates = [0.15, 0.5, 1, 2, 3.5, 5];
+  const candidates = [];
+
+  for (const candidate of baseCandidates) {
+    const clamped = Math.max(0, Math.min(candidate, upperBound));
+    if (candidates.length === 0 || Math.abs(candidates[candidates.length - 1] - clamped) > 0.08) {
+      candidates.push(Number(clamped.toFixed(3)));
+    }
+  }
+
+  if (upperBound > 0.25) {
+    const fallback = Number(upperBound.toFixed(3));
+    if (Math.abs(candidates[candidates.length - 1] - fallback) > 0.08) {
+      candidates.push(fallback);
+    }
+  }
+
+  return candidates;
+}
+
+export function analyzeFrameLuma(data, options = {}) {
+  const bytes = data instanceof Uint8ClampedArray ? data : new Uint8ClampedArray(data ?? []);
+  const pixelCount = Math.floor(bytes.length / 4);
+  if (pixelCount === 0) {
+    return {
+      sampleCount: 0,
+      averageLuma: 0,
+      darkRatio: 1,
+      isBlackFrame: true
+    };
+  }
+
+  const {
+    darknessThreshold = 18,
+    maxDarkRatio = 0.985,
+    averageThreshold = 22,
+    stride = 16
+  } = options;
+
+  let samples = 0;
+  let darkSamples = 0;
+  let lumaTotal = 0;
+
+  for (let index = 0; index < pixelCount; index += stride) {
+    const offset = index * 4;
+    const red = bytes[offset];
+    const green = bytes[offset + 1];
+    const blue = bytes[offset + 2];
+    const alpha = bytes[offset + 3];
+    const luma = alpha === 0 ? 0 : 0.2126 * red + 0.7152 * green + 0.0722 * blue;
+    lumaTotal += luma;
+    samples += 1;
+
+    if (luma <= darknessThreshold) {
+      darkSamples += 1;
+    }
+  }
+
+  const averageLuma = samples > 0 ? lumaTotal / samples : 0;
+  const darkRatio = samples > 0 ? darkSamples / samples : 1;
+  const isBlackFrame = averageLuma <= averageThreshold && darkRatio >= maxDarkRatio;
+
+  return {
+    sampleCount: samples,
+    averageLuma,
+    darkRatio,
+    isBlackFrame
+  };
+}