diff --git a/src/opus_multistream.h b/src/opus_multistream.h
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+++ b/src/opus_multistream.h
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+/* Copyright (c) 2011 Xiph.Org Foundation
+   Written by Jean-Marc Valin */
+/*
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions
+   are met:
+
+   - Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+
+   - Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
+   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#ifndef OPUS_MULTISTREAM_H
+#define OPUS_MULTISTREAM_H
+
+#include "opus.h"
+
+typedef struct OpusMSEncoder OpusMSEncoder;
+typedef struct OpusMSDecoder OpusMSDecoder;
+
+OPUS_EXPORT OpusMSEncoder *opus_multistream_encoder_create(
+      int Fs,                     /* Sampling rate of input signal (Hz) */
+      int channels,               /* Number of channels (1/2) in input signal */
+      int streams,
+      int coupled_streams,
+      unsigned char *mapping,
+      int application             /* Coding mode (OPUS_APPLICATION_VOIP/OPUS_APPLICATION_AUDIO) */
+);
+
+OPUS_EXPORT int opus_multistream_encoder_init(
+      OpusMSEncoder *st,            /* Encoder state */
+      int Fs,                     /* Sampling rate of input signal (Hz) */
+      int channels,               /* Number of channels (1/2) in input signal */
+      int streams,
+      int coupled_streams,
+      unsigned char *mapping,
+      int application             /* Coding mode (OPUS_APPLICATION_VOIP/OPUS_APPLICATION_AUDIO) */
+);
+
+/* Returns length of the data payload (in bytes) */
+OPUS_EXPORT int opus_multistream_encode(
+    OpusMSEncoder *st,            /* Encoder state */
+    const opus_int16 *pcm,      /* Input signal (interleaved if 2 channels). length is frame_size*channels */
+    int frame_size,             /* Number of samples per frame of input signal */
+    unsigned char *data,        /* Output payload (no more than max_data_bytes long) */
+    int max_data_bytes          /* Allocated memory for payload; don't use for controlling bitrate */
+);
+
+/* Returns length of the data payload (in bytes) */
+OPUS_EXPORT int opus_multistream_encode_float(
+      OpusMSEncoder *st,            /* Encoder state */
+      const float *pcm,      /* Input signal (interleaved if 2 channels). length is frame_size*channels */
+      int frame_size,             /* Number of samples per frame of input signal */
+      unsigned char *data,        /* Output payload (no more than max_data_bytes long) */
+      int max_data_bytes          /* Allocated memory for payload; don't use for controlling bitrate */
+  );
+
+OPUS_EXPORT void opus_multistream_encoder_destroy(OpusMSEncoder *st);
+
+OPUS_EXPORT int opus_multistream_encoder_ctl(OpusMSEncoder *st, int request, ...);
+
+OPUS_EXPORT OpusMSDecoder *opus_multistream_decoder_create(
+      int Fs,                     /* Sampling rate of input signal (Hz) */
+      int channels,               /* Number of channels (1/2) in input signal */
+      int streams,
+      int coupled_streams,
+      unsigned char *mapping
+);
+
+OPUS_EXPORT int opus_multistream_decoder_init(
+      OpusMSDecoder *st,            /* Encoder state */
+      int Fs,                     /* Sampling rate of input signal (Hz) */
+      int channels,               /* Number of channels (1/2) in input signal */
+      int streams,
+      int coupled_streams,
+      unsigned char *mapping
+);
+
+/* Returns the number of samples decoded or a negative error code */
+OPUS_EXPORT int opus_multistream_decode(
+    OpusMSDecoder *st,            /* Decoder state */
+    const unsigned char *data,  /* Input payload. Use a NULL pointer to indicate packet loss */
+    int len,                    /* Number of bytes in payload */
+    opus_int16 *pcm,            /* Output signal (interleaved if 2 channels). length is frame_size*channels */
+    int frame_size,             /* Number of samples per frame of input signal */
+    int decode_fec              /* Flag (0/1) to request that any in-band forward error correction data be */
+                                /* decoded. If no such data is available the frame is decoded as if it were lost. */
+);
+
+/* Returns the number of samples decoded or a negative error code */
+OPUS_EXPORT int opus_multistream_decode_float(
+    OpusMSDecoder *st,            /* Decoder state */
+    const unsigned char *data,  /* Input payload. Use a NULL pointer to indicate packet loss */
+    int len,                    /* Number of bytes in payload */
+    float *pcm,                 /* Output signal (interleaved if 2 channels). length is frame_size*channels */
+    int frame_size,             /* Number of samples per frame of input signal */
+    int decode_fec              /* Flag (0/1) to request that any in-band forward error correction data be */
+                                /* decoded. If no such data is available the frame is decoded as if it were lost. */
+);
+
+OPUS_EXPORT int opus_multistream_decoder_ctl(OpusMSDecoder *st, int request, ...);
+
+OPUS_EXPORT void opus_multistream_decoder_destroy(OpusMSDecoder *st);
+
+#endif /* OPUS_MULTISTREAM_H */