Apple quietly shipped everything you need to build a real-time translator — so I built one

Описание и применение

Wakaru — приложение macOS, которое преобразует любой звук, воспроизводимый на компьютере, в субтитры с переводом в реальном времени, полностью на устройстве, без отправки данных в облако.

Задача

Need real‑time, on‑device subtitles for confidential meetings on macOS without sending audio to the cloud.

Результат

Wakaru delivers live, on‑device subtitles for any audio on macOS 26+, achieving near‑real‑time latency, 10 source languages, 22 target languages, and optional high‑accuracy LLM mode, all with zero external dependencies.

Рабочий процесс

• Capture system audio at 16 kHz via ScreenCaptureKit
• Use SpeechAnalyzer with .fastResults and prepareToAnalyze for low latency
• Collect complete sentences, then translate with Translation framework or Apple Intelligence LLM
• Render subtitles on a transparent NSPanel overlay
• Handle sample rate, reporting cadence, lazy loading, and shutdown optimizations
• Use content anchors to avoid re‑translation of rewritten text
• Manage TranslationSession via invisible .translationTask in SwiftUI
• Implement LLM guardrails: 2.5 s deadline, session reset every 10 sentences, reject degenerate output

Доказательства

Wakaru runs on macOS 26+ (Apple silicon). It's free for 14 days (and stays free for 1 hour/day after that), with a one-time purchase for unlimited time — no subscription

Источник

SpeechAnalyzer prefers 16 kHz audio. My first version captured at 48 kHz and resampled with AVAudioConverter — and the first caption took seconds to appear.

Источник

Translation framework only works inside SwiftUI .translationTask view modifier.

Источник