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  "markdown": "ALAC (Apple Lossless Audio Codec) is Apple's lossless format. It compresses about as well as [FLAC](/codecs/audio/flac/) and decodes back to identical samples, but it lives in MP4/`.m4a` files that iPhones, iPods, Macs, Apple TV and iTunes/Music play natively. Use ALAC when the destination is an Apple library; use FLAC for everything else. Apple's reference implementation is open source (Apache 2.0).\n\nALAC stores integer PCM at 16, 20, 24 or 32 bits with 1–8 channels. It cannot store floating-point audio.\n\n## Encoding\n\n```sh\nffmpeg -i input.flac -c:a alac output.m4a\n```\n\nFFmpeg's `alac` encoder is the usual route off a Mac. It writes **16-bit or 24-bit** ALAC only: a 32-bit integer source is stored as 24-bit, so the lowest eight bits are lost. Apple's reference encoder handles all four bit depths.\n\n`-compression_level` only goes 0–2 (default 2) and the result changes size, not fidelity. The extra `-min_prediction_order` and `-max_prediction_order` options (defaults 4 and 6) are rarely worth touching.\n\n## Converting to and from FLAC\n\nALAC and FLAC are both lossless, so converting between them loses nothing as long as the bit depth is preserved:\n\n```sh\nffmpeg -i input.m4a -c:a flac output.flac\nffmpeg -i input.flac -c:a alac output.m4a\n```\n\n## Compatibility\n\n- Apple hardware and software play ALAC natively, as does Safari. Chrome, Edge and Firefox do not list ALAC as a supported browser audio format.\n- Outside Apple's ecosystem, support is software-only (FFmpeg-based players such as mpv and VLC); hardware players and car stereos are far less likely to handle it than FLAC.\n- ALAC also appears in `.caf` files, mainly as an Apple tool format.\n\nFor anything web-facing, publish FLAC (or a lossy codec) instead.\n"
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