Files
kapteins-daagbok/client/src/utils/captureVideoFrame.ts
T
elpatron 73467f2263 fix: live journal camera save on Android
Use native camera picker on mobile, add preview-and-save step, and
harden canvas capture with toDataURL fallback when toBlob fails.

Co-authored-by: Cursor <cursoragent@cursor.com>
2026-06-01 10:45:54 +02:00

60 lines
1.9 KiB
TypeScript

/** Capture current video frame as JPEG blob (with Android-safe fallbacks). */
export async function captureVideoFrame(video: HTMLVideoElement, quality = 0.92): Promise<Blob> {
const width = video.videoWidth
const height = video.videoHeight
if (!width || !height) {
throw new Error('video_frame_not_ready')
}
const canvas = document.createElement('canvas')
canvas.width = width
canvas.height = height
const ctx = canvas.getContext('2d')
if (!ctx) {
throw new Error('canvas_context_unavailable')
}
ctx.drawImage(video, 0, 0, width, height)
const blob = await canvasToJpegBlob(canvas, quality)
if (blob) return blob
const dataUrl = canvas.toDataURL('image/jpeg', quality)
const response = await fetch(dataUrl)
const fallback = await response.blob()
if (!fallback.size) {
throw new Error('capture_encode_failed')
}
return fallback
}
function canvasToJpegBlob(canvas: HTMLCanvasElement, quality: number): Promise<Blob | null> {
return new Promise((resolve) => {
let settled = false
const finish = (blob: Blob | null) => {
if (settled) return
settled = true
window.clearTimeout(timer)
resolve(blob)
}
const timer = window.setTimeout(() => finish(null), 3000)
try {
canvas.toBlob((blob) => finish(blob), 'image/jpeg', quality)
} catch {
finish(null)
}
})
}
/** Mobile: native camera via file input is more reliable than getUserMedia + canvas. */
export function preferNativeCameraPicker(): boolean {
if (typeof window === 'undefined') return false
const ua = navigator.userAgent
if (/Android|iPhone|iPad|iPod/i.test(ua)) return true
const touch = 'ontouchstart' in window || navigator.maxTouchPoints > 0
const coarse = window.matchMedia('(pointer: coarse)').matches
const narrow = window.matchMedia('(max-width: 768px)').matches
return touch && (coarse || narrow)
}