如果 Opus 是丢失的, 和 M4A 是无损失的( 例如 MP3 {WAV), M4A 并不比 Opus 更好, 您无法收回已经丢弃的信息。 如果 Opus 是无损失的, M4A 是丢失的, M4A 代码压缩; 在 192 kbps, 结果对大多数内容来说是透明的 。
Does the Opus to M4A converter keep ID3 / metadata tags?
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Yes — title, artist, album, year, track number, and album art are read from the Opus container and written into the M4A container where the format supports tags. All common targets (MP3, AAC, FLAC, OGG) handle tags fine; raw WAV does not.
我可以批量转换成 Opus 成百上千个文件 M4A 吗?
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Yes — drop a folder of Opus files in and we process them in parallel. Premium has more parallel workers and no per-file size cap, so a 500-file batch finishes in minutes rather than tens of minutes.
Will the M4A keep the same sample rate as Opus?
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默认是 。 - 48 kHz Opus 保留48 kHz在 M4A 中。 如果您需要降为兼容性样本( 96 kHz 44.1 kHz 用于 CD 燃烧), 样本率选项将在同一编码通行证中应用高质量的重印。
Yes — uploaded Opus files are processed in isolated workers and deleted within minutes. We never play back, store long-term, or share the audio content. The full retention window is in /privacy/.
转换一个 1小时 Opus 到 M4A 需要多久?
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Same-codec re-mux: 10 to 30 seconds. Re-encode to a different codec: typically 10 to 20% of source duration, so a 1-hour Opus → M4A finishes in 6 to 12 minutes. Batch jobs parallelize across workers for further speedups.
Why is the M4A louder or quieter than the Opus source?
If the Opus download is unprotected (no DRM), yes. DRM-encrypted streams (Spotify, Apple Music tracks) are encrypted at the bit level and we cannot process them. Bandcamp, SoundCloud downloads, personal recordings, and podcast files convert cleanly.