更新

admin/src/utils/call-video-screenshot.ts

@@ -0,0 +1,35 @@
+/** 从视频通话区域截取当前最大的一路 video 帧（WebRTC 画面） */
+export async function captureVideoFrameFromElement(
+  container: HTMLElement
+): Promise<Blob | null> {
+  const videos = Array.from(container.querySelectorAll('video')) as HTMLVideoElement[]
+  let best: HTMLVideoElement | null = null
+  let bestArea = 0
+  for (const v of videos) {
+    if (v.readyState < 2) continue
+    const vw = v.videoWidth || v.clientWidth
+    const vh = v.videoHeight || v.clientHeight
+    const area = vw * vh
+    if (area > bestArea) {
+      bestArea = area
+      best = v
+    }
+  }
+  if (!best) return null
+  const vw = best.videoWidth || best.clientWidth
+  const vh = best.videoHeight || best.clientHeight
+  if (!vw || !vh) return null
+  const canvas = document.createElement('canvas')
+  canvas.width = vw
+  canvas.height = vh
+  const ctx = canvas.getContext('2d')
+  if (!ctx) return null
+  try {
+    ctx.drawImage(best, 0, 0, vw, vh)
+  } catch {
+    return null
+  }
+  return new Promise((resolve) => {
+    canvas.toBlob((b) => resolve(b), 'image/jpeg', 0.92)
+  })
+}