216 lines
		
	
	
		
			9.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			216 lines
		
	
	
		
			9.7 KiB
		
	
	
	
		
			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 ) ) { | ||
|  |             celt_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 ) ) { | ||
|  |             celt_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 */ | ||
|  |             celt_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 */ | ||
|  |     celt_assert( inLen >= S->Fs_in_kHz ); | ||
|  |     /* Delay can't exceed the 1 ms of buffering */ | ||
|  |     celt_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; | ||
|  | } |