opus_multistream.h(3)

🌸 opus_multistream.h 🌸

okay bestie, welcome to the Opus multistream header — this is the Opus reference implementation multistream API, and yes she is that girl 💅. Sit down, grab a boba, we're going through every single function together, no skips, no cap.

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✨ NAME ✨

opus_multistream.h — the Opus reference implementation multistream API. that's the whole vibe. it's a C header, it's giving "many streams, one file" 🦋

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🎀 SYNOPSIS 🎀

#include 'opus.h'

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🌈 Macros 🌈

• #define OPUS_MULTISTREAM_GET_ENCODER_STATE(x, y) — grabs the encoder state for one individual stream inside a multistream encoder. lowkey the key to the whole encoder kingdom 🔑
• #define OPUS_MULTISTREAM_GET_DECODER_STATE(x, y) — same energy but for the decoder side: gets the decoder state for an individual stream of a multistream decoder 💖

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🦋 Typedefs 🦋

• typedef struct OpusMSEncoder OpusMSEncoder — the Opus multistream encoder state. she's the main character 👑
• typedef struct OpusMSDecoder OpusMSDecoder — the Opus multistream decoder state. the other main character, they're a duo fr fr ✨

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💜 Functions 💜

🎧 Multistream encoder functions 🎧

• opus_int32 opus_multistream_encoder_get_size (int streams, int coupled_streams) — tells you how big an OpusMSEncoder structure is, so you know how much room to set aside 🫶
• opus_int32 opus_multistream_surround_encoder_get_size (int channels, int mapping_family) — the surround-flavoured size-getter. it's the channels + mapping_family version, and yes she exists, she's just chillin' in the list 🌈
• OpusMSEncoder * opus_multistream_encoder_create (opus_int32 Fs, int channels, int streams, int coupled_streams, const unsigned char *mapping, int application, int *error) — allocates and initializes a multistream encoder state. one-stop shop, we love a two-for-one 💅
• OpusMSEncoder * opus_multistream_surround_encoder_create (opus_int32 Fs, int channels, int mapping_family, int *streams, int *coupled_streams, unsigned char *mapping, int application, int *error) — the surround encoder's create function. note she takes mapping_family and hands you back streams, coupled_streams and mapping through pointers, so you get the deets after the fact 👀
• int opus_multistream_encoder_init (OpusMSEncoder *st, opus_int32 Fs, int channels, int streams, int coupled_streams, const unsigned char *mapping, int application) — initializes a multistream encoder state that you already allocated yourself. DIY girlies rise 🧚
• int opus_multistream_surround_encoder_init (OpusMSEncoder *st, opus_int32 Fs, int channels, int mapping_family, int *streams, int *coupled_streams, unsigned char *mapping, int application) — the surround version of the init-you-already-allocated situation. same deal, mapping_family in, streams/coupled_streams/mapping out through pointers ✨
• int opus_multistream_encode (OpusMSEncoder *st, const opus_int16 *pcm, int frame_size, unsigned char *data, opus_int32 max_data_bytes) — encodes one multistream Opus frame 🔥
• int opus_multistream_encode24 (OpusMSEncoder *st, const opus_int32 *pcm, int frame_size, unsigned char *data, opus_int32 max_data_bytes) — also encodes a multistream Opus frame. yep, same description, different pcm type — she takes const opus_int32 *pcm and that's the whole plot 💀
• int opus_multistream_encode_float (OpusMSEncoder *st, const float *pcm, int frame_size, unsigned char *data, opus_int32 max_data_bytes) — encodes a multistream Opus frame from floating point input 🌸
• void opus_multistream_encoder_destroy (OpusMSEncoder *st) — frees an OpusMSEncoder that was allocated by opus_multistream_encoder_create(). clean up after yourself bestie, we don't do leaks here 🫧
• int opus_multistream_encoder_ctl (OpusMSEncoder *st, int request,...) — runs a CTL function on a multistream Opus encoder. variadic, mysterious, iconic 🎀

🎶 Multistream decoder functions 🎶

• opus_int32 opus_multistream_decoder_get_size (int streams, int coupled_streams) — tells you the size of an OpusMSDecoder structure. same energy as her encoder sister, just decoder-flavoured 💖
• OpusMSDecoder * opus_multistream_decoder_create (opus_int32 Fs, int channels, int streams, int coupled_streams, const unsigned char *mapping, int *error) — allocates and initializes a multistream decoder state. she's ready out the gate ✨
• int opus_multistream_decoder_init (OpusMSDecoder *st, opus_int32 Fs, int channels, int streams, int coupled_streams, const unsigned char *mapping) — initializes a decoder state object you already allocated. note: no application arg here, decoders don't need one 🦋
• int opus_multistream_decode (OpusMSDecoder *st, const unsigned char *data, opus_int32 len, opus_int16 *pcm, int frame_size, int decode_fec) — decodes a multistream Opus packet 🔥
• int opus_multistream_decode24 (OpusMSDecoder *st, const unsigned char *data, opus_int32 len, opus_int32 *pcm, int frame_size, int decode_fec) — decodes a multistream Opus packet. again, same one-liner, different output type — opus_int32 *pcm this time 🙈
• int opus_multistream_decode_float (OpusMSDecoder *st, const unsigned char *data, opus_int32 len, float *pcm, int frame_size, int decode_fec) — decodes a multistream Opus packet with floating point output 🌸
• int opus_multistream_decoder_ctl (OpusMSDecoder *st, int request,...) — runs a CTL function on a multistream Opus decoder 💅
• void opus_multistream_decoder_destroy (OpusMSDecoder *st) — frees an OpusMSDecoder allocated by opus_multistream_decoder_create(). say bye bye properly 🫶

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💫 Detailed Description 💫

Opus reference implementation multistream API.

that's it, that's the description. short, sweet, does exactly what it says on the tin ✨

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🌟 Author 🌟

Generated automatically by Doxygen for Opus from the source code.

so technically no human author wrote this — Doxygen did, straight off the source. respect the automation honestly 🤖💖

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🎀 SEE ALSO 🎀

not a single SEE ALSO in sight, bestie. this page stands alone, independent, main character energy, no supporting cast needed 💅

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okay that's the whole page, every macro, every typedef, every function signature, every one-liner, all of it, nothing dropped 🫶

this was Opus version 1.6.1, dated Thu Jan 29 2026 14:35:32, and it's the opus_multistream.h(3) manual page — thanks for reading bestie, go encode some streams, mwah 💋✨