Add copy of opus library in deps/third_party.

opus/silk/resampler.c

+/***********************************************************************
+Copyright (c) 2006-2011, Skype Limited. All rights reserved.
+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.
+- Neither the name of Internet Society, IETF or IETF Trust, nor the 
+names of specific contributors, may be used to endorse or promote
+products derived from this software without specific prior written
+permission.
+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 COPYRIGHT OWNER 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.
+***********************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+/*
+ * Matrix of resampling methods used:
+ *                                 Fs_out (kHz)
+ *                        8      12     16     24     48
+ *
+ *               8        C      UF     U      UF     UF
+ *              12        AF     C      UF     U      UF
+ * Fs_in (kHz)  16        D      AF     C      UF     UF
+ *              24        AF     D      AF     C      U
+ *              48        AF     AF     AF     D      C
+ *
+ * C   -> Copy (no resampling)
+ * D   -> Allpass-based 2x downsampling
+ * U   -> Allpass-based 2x upsampling
+ * UF  -> Allpass-based 2x upsampling followed by FIR interpolation
+ * AF  -> AR2 filter followed by FIR interpolation
+ */
+
+#include "resampler_private.h"
+
+/* Tables with delay compensation values to equalize total delay for different modes */
+static const opus_int8 delay_matrix_enc[ 5 ][ 3 ] = {
+/* in  \ out  8  12  16 */
+/*  8 */   {  6,  0,  3 },
+/* 12 */   {  0,  7,  3 },
+/* 16 */   {  0,  1, 10 },
+/* 24 */   {  0,  2,  6 },
+/* 48 */   { 18, 10, 12 }
+};
+
+static const opus_int8 delay_matrix_dec[ 3 ][ 5 ] = {
+/* in  \ out  8  12  16  24  48 */
+/*  8 */   {  4,  0,  2,  0,  0 },
+/* 12 */   {  0,  9,  4,  7,  4 },
+/* 16 */   {  0,  3, 12,  7,  7 }
+};
+
+/* Simple way to make [8000, 12000, 16000, 24000, 48000] to [0, 1, 2, 3, 4] */
+#define rateID(R) ( ( ( ((R)>>12) - ((R)>16000) ) >> ((R)>24000) ) - 1 )
+
+#define USE_silk_resampler_copy                     (0)
+#define USE_silk_resampler_private_up2_HQ_wrapper   (1)
+#define USE_silk_resampler_private_IIR_FIR          (2)
+#define USE_silk_resampler_private_down_FIR         (3)
+
+/* Initialize/reset the resampler state for a given pair of input/output sampling rates */
+opus_int silk_resampler_init(
+    silk_resampler_state_struct *S,                 /* I/O  Resampler state                                             */
+    opus_int32                  Fs_Hz_in,           /* I    Input sampling rate (Hz)                                    */
+    opus_int32                  Fs_Hz_out,          /* I    Output sampling rate (Hz)                                   */
+    opus_int                    forEnc              /* I    If 1: encoder; if 0: decoder                                */
+)
+{
+    opus_int up2x;
+
+    /* Clear state */
+    silk_memset( S, 0, sizeof( silk_resampler_state_struct ) );
+
+    /* Input checking */
+    if( forEnc ) {
+        if( ( Fs_Hz_in  != 8000 && Fs_Hz_in  != 12000 && Fs_Hz_in  != 16000 && Fs_Hz_in  != 24000 && Fs_Hz_in  != 48000 ) ||
+            ( Fs_Hz_out != 8000 && Fs_Hz_out != 12000 && Fs_Hz_out != 16000 ) ) {
+            silk_assert( 0 );
+            return -1;
+        }
+        S->inputDelay = delay_matrix_enc[ rateID( Fs_Hz_in ) ][ rateID( Fs_Hz_out ) ];
+    } else {
+        if( ( Fs_Hz_in  != 8000 && Fs_Hz_in  != 12000 && Fs_Hz_in  != 16000 ) ||
+            ( Fs_Hz_out != 8000 && Fs_Hz_out != 12000 && Fs_Hz_out != 16000 && Fs_Hz_out != 24000 && Fs_Hz_out != 48000 ) ) {
+            silk_assert( 0 );
+            return -1;
+        }
+        S->inputDelay = delay_matrix_dec[ rateID( Fs_Hz_in ) ][ rateID( Fs_Hz_out ) ];
+    }
+
+    S->Fs_in_kHz  = silk_DIV32_16( Fs_Hz_in,  1000 );
+    S->Fs_out_kHz = silk_DIV32_16( Fs_Hz_out, 1000 );
+
+    /* Number of samples processed per batch */
+    S->batchSize = S->Fs_in_kHz * RESAMPLER_MAX_BATCH_SIZE_MS;
+
+    /* Find resampler with the right sampling ratio */
+    up2x = 0;
+    if( Fs_Hz_out > Fs_Hz_in ) {
+        /* Upsample */
+        if( Fs_Hz_out == silk_MUL( Fs_Hz_in, 2 ) ) {                            /* Fs_out : Fs_in = 2 : 1 */
+            /* Special case: directly use 2x upsampler */
+            S->resampler_function = USE_silk_resampler_private_up2_HQ_wrapper;
+        } else {
+            /* Default resampler */
+            S->resampler_function = USE_silk_resampler_private_IIR_FIR;
+            up2x = 1;
+        }
+    } else if ( Fs_Hz_out < Fs_Hz_in ) {
+        /* Downsample */
+         S->resampler_function = USE_silk_resampler_private_down_FIR;
+        if( silk_MUL( Fs_Hz_out, 4 ) == silk_MUL( Fs_Hz_in, 3 ) ) {             /* Fs_out : Fs_in = 3 : 4 */
+            S->FIR_Fracs = 3;
+            S->FIR_Order = RESAMPLER_DOWN_ORDER_FIR0;
+            S->Coefs = silk_Resampler_3_4_COEFS;
+        } else if( silk_MUL( Fs_Hz_out, 3 ) == silk_MUL( Fs_Hz_in, 2 ) ) {      /* Fs_out : Fs_in = 2 : 3 */
+            S->FIR_Fracs = 2;
+            S->FIR_Order = RESAMPLER_DOWN_ORDER_FIR0;
+            S->Coefs = silk_Resampler_2_3_COEFS;
+        } else if( silk_MUL( Fs_Hz_out, 2 ) == Fs_Hz_in ) {                     /* Fs_out : Fs_in = 1 : 2 */
+            S->FIR_Fracs = 1;
+            S->FIR_Order = RESAMPLER_DOWN_ORDER_FIR1;
+            S->Coefs = silk_Resampler_1_2_COEFS;
+        } else if( silk_MUL( Fs_Hz_out, 3 ) == Fs_Hz_in ) {                     /* Fs_out : Fs_in = 1 : 3 */
+            S->FIR_Fracs = 1;
+            S->FIR_Order = RESAMPLER_DOWN_ORDER_FIR2;
+            S->Coefs = silk_Resampler_1_3_COEFS;
+        } else if( silk_MUL( Fs_Hz_out, 4 ) == Fs_Hz_in ) {                     /* Fs_out : Fs_in = 1 : 4 */
+            S->FIR_Fracs = 1;
+            S->FIR_Order = RESAMPLER_DOWN_ORDER_FIR2;
+            S->Coefs = silk_Resampler_1_4_COEFS;
+        } else if( silk_MUL( Fs_Hz_out, 6 ) == Fs_Hz_in ) {                     /* Fs_out : Fs_in = 1 : 6 */
+            S->FIR_Fracs = 1;
+            S->FIR_Order = RESAMPLER_DOWN_ORDER_FIR2;
+            S->Coefs = silk_Resampler_1_6_COEFS;
+        } else {
+            /* None available */
+            silk_assert( 0 );
+            return -1;
+        }
+    } else {
+        /* Input and output sampling rates are equal: copy */
+        S->resampler_function = USE_silk_resampler_copy;
+    }
+
+    /* Ratio of input/output samples */
+    S->invRatio_Q16 = silk_LSHIFT32( silk_DIV32( silk_LSHIFT32( Fs_Hz_in, 14 + up2x ), Fs_Hz_out ), 2 );
+    /* Make sure the ratio is rounded up */
+    while( silk_SMULWW( S->invRatio_Q16, Fs_Hz_out ) < silk_LSHIFT32( Fs_Hz_in, up2x ) ) {
+        S->invRatio_Q16++;
+    }
+
+    return 0;
+}
+
+/* Resampler: convert from one sampling rate to another */
+/* Input and output sampling rate are at most 48000 Hz  */
+opus_int silk_resampler(
+    silk_resampler_state_struct *S,                 /* I/O  Resampler state                                             */
+    opus_int16                  out[],              /* O    Output signal                                               */
+    const opus_int16            in[],               /* I    Input signal                                                */
+    opus_int32                  inLen               /* I    Number of input samples                                     */
+)
+{
+    opus_int nSamples;
+
+    /* Need at least 1 ms of input data */
+    silk_assert( inLen >= S->Fs_in_kHz );
+    /* Delay can't exceed the 1 ms of buffering */
+    silk_assert( S->inputDelay <= S->Fs_in_kHz );
+
+    nSamples = S->Fs_in_kHz - S->inputDelay;
+
+    /* Copy to delay buffer */
+    silk_memcpy( &S->delayBuf[ S->inputDelay ], in, nSamples * sizeof( opus_int16 ) );
+
+    switch( S->resampler_function ) {
+        case USE_silk_resampler_private_up2_HQ_wrapper:
+            silk_resampler_private_up2_HQ_wrapper( S, out, S->delayBuf, S->Fs_in_kHz );
+            silk_resampler_private_up2_HQ_wrapper( S, &out[ S->Fs_out_kHz ], &in[ nSamples ], inLen - S->Fs_in_kHz );
+            break;
+        case USE_silk_resampler_private_IIR_FIR:
+            silk_resampler_private_IIR_FIR( S, out, S->delayBuf, S->Fs_in_kHz );
+            silk_resampler_private_IIR_FIR( S, &out[ S->Fs_out_kHz ], &in[ nSamples ], inLen - S->Fs_in_kHz );
+            break;
+        case USE_silk_resampler_private_down_FIR:
+            silk_resampler_private_down_FIR( S, out, S->delayBuf, S->Fs_in_kHz );
+            silk_resampler_private_down_FIR( S, &out[ S->Fs_out_kHz ], &in[ nSamples ], inLen - S->Fs_in_kHz );
+            break;
+        default:
+            silk_memcpy( out, S->delayBuf, S->Fs_in_kHz * sizeof( opus_int16 ) );
+            silk_memcpy( &out[ S->Fs_out_kHz ], &in[ nSamples ], ( inLen - S->Fs_in_kHz ) * sizeof( opus_int16 ) );
+    }
+
+    /* Copy to delay buffer */
+    silk_memcpy( S->delayBuf, &in[ inLen - S->inputDelay ], S->inputDelay * sizeof( opus_int16 ) );
+
+    return 0;
+}