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#codec
2 articles
01
2026-08-25
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Audio Codecs
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★ MEMBER
·
PAPER
·
11 min read
Why Opus Won — The Design of a Modern Audio Codec
Audio codecs used to split cleanly into speech codecs and music codecs. Opus ended the split by stacking two engines, SILK and CELT, inside a single bitstream. This piece works up from zero: how linear prediction and the MDCT divide the spectrum between them, why CELT refuses to let band energy collapse, what actually sets a codec's latency, and the technical and institutional reasons Opus became WebRTC's mandatory codec.
02
2026-08-13
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Audio Codecs
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FREE
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8 min read
Audio Compression from Scratch — The Art of Discarding What You Cannot Hear
How does MP3 sound 'the same' at less than a tenth of the size? We build up audio codecs from zero — auditory masking, the MDCT, and bit allocation — and finish with when to reach for MP3, AAC, or Opus.