1 /***********************************************************************
2 Copyright (c) 2006-2011, Skype Limited. All rights reserved.
3 Redistribution and use in source and binary forms, with or without
4 modification, are permitted provided that the following conditions
5 are met:
6 - Redistributions of source code must retain the above copyright notice,
7 this list of conditions and the following disclaimer.
8 - Redistributions in binary form must reproduce the above copyright
9 notice, this list of conditions and the following disclaimer in the
10 documentation and/or other materials provided with the distribution.
11 - Neither the name of Internet Society, IETF or IETF Trust, nor the
12 names of specific contributors, may be used to endorse or promote
13 products derived from this software without specific prior written
14 permission.
15 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
19 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
20 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
21 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
23 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
24 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25 POSSIBILITY OF SUCH DAMAGE.
26 ***********************************************************************/
27
28 #ifdef HAVE_CONFIG_H
29 #include "config.h"
30 #endif
31
32 #include "SigProc_FIX.h"
33 #include "resampler_private.h"
34 #include "stack_alloc.h"
35
silk_resampler_private_IIR_FIR_INTERPOL(opus_int16 * out,opus_int16 * buf,opus_int32 max_index_Q16,opus_int32 index_increment_Q16)36 static OPUS_INLINE opus_int16 *silk_resampler_private_IIR_FIR_INTERPOL(
37 opus_int16 *out,
38 opus_int16 *buf,
39 opus_int32 max_index_Q16,
40 opus_int32 index_increment_Q16
41 )
42 {
43 opus_int32 index_Q16, res_Q15;
44 opus_int16 *buf_ptr;
45 opus_int32 table_index;
46
47 /* Interpolate upsampled signal and store in output array */
48 for( index_Q16 = 0; index_Q16 < max_index_Q16; index_Q16 += index_increment_Q16 ) {
49 table_index = silk_SMULWB( index_Q16 & 0xFFFF, 12 );
50 buf_ptr = &buf[ index_Q16 >> 16 ];
51
52 res_Q15 = silk_SMULBB( buf_ptr[ 0 ], silk_resampler_frac_FIR_12[ table_index ][ 0 ] );
53 res_Q15 = silk_SMLABB( res_Q15, buf_ptr[ 1 ], silk_resampler_frac_FIR_12[ table_index ][ 1 ] );
54 res_Q15 = silk_SMLABB( res_Q15, buf_ptr[ 2 ], silk_resampler_frac_FIR_12[ table_index ][ 2 ] );
55 res_Q15 = silk_SMLABB( res_Q15, buf_ptr[ 3 ], silk_resampler_frac_FIR_12[ table_index ][ 3 ] );
56 res_Q15 = silk_SMLABB( res_Q15, buf_ptr[ 4 ], silk_resampler_frac_FIR_12[ 11 - table_index ][ 3 ] );
57 res_Q15 = silk_SMLABB( res_Q15, buf_ptr[ 5 ], silk_resampler_frac_FIR_12[ 11 - table_index ][ 2 ] );
58 res_Q15 = silk_SMLABB( res_Q15, buf_ptr[ 6 ], silk_resampler_frac_FIR_12[ 11 - table_index ][ 1 ] );
59 res_Q15 = silk_SMLABB( res_Q15, buf_ptr[ 7 ], silk_resampler_frac_FIR_12[ 11 - table_index ][ 0 ] );
60 *out++ = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( res_Q15, 15 ) );
61 }
62 return out;
63 }
64 /* Upsample using a combination of allpass-based 2x upsampling and FIR interpolation */
silk_resampler_private_IIR_FIR(void * SS,opus_int16 out[],const opus_int16 in[],opus_int32 inLen)65 void silk_resampler_private_IIR_FIR(
66 void *SS, /* I/O Resampler state */
67 opus_int16 out[], /* O Output signal */
68 const opus_int16 in[], /* I Input signal */
69 opus_int32 inLen /* I Number of input samples */
70 )
71 {
72 silk_resampler_state_struct *S = (silk_resampler_state_struct *)SS;
73 opus_int32 nSamplesIn;
74 opus_int32 max_index_Q16, index_increment_Q16;
75 VARDECL( opus_int16, buf );
76 SAVE_STACK;
77
78 ALLOC( buf, 2 * S->batchSize + RESAMPLER_ORDER_FIR_12, opus_int16 );
79
80 /* Copy buffered samples to start of buffer */
81 silk_memcpy( buf, S->sFIR.i16, RESAMPLER_ORDER_FIR_12 * sizeof( opus_int16 ) );
82
83 /* Iterate over blocks of frameSizeIn input samples */
84 index_increment_Q16 = S->invRatio_Q16;
85 while( 1 ) {
86 nSamplesIn = silk_min( inLen, S->batchSize );
87
88 /* Upsample 2x */
89 silk_resampler_private_up2_HQ( S->sIIR, &buf[ RESAMPLER_ORDER_FIR_12 ], in, nSamplesIn );
90
91 max_index_Q16 = silk_LSHIFT32( nSamplesIn, 16 + 1 ); /* + 1 because 2x upsampling */
92 out = silk_resampler_private_IIR_FIR_INTERPOL( out, buf, max_index_Q16, index_increment_Q16 );
93 in += nSamplesIn;
94 inLen -= nSamplesIn;
95
96 if( inLen > 0 ) {
97 /* More iterations to do; copy last part of filtered signal to beginning of buffer */
98 silk_memcpy( buf, &buf[ nSamplesIn << 1 ], RESAMPLER_ORDER_FIR_12 * sizeof( opus_int16 ) );
99 } else {
100 break;
101 }
102 }
103
104 /* Copy last part of filtered signal to the state for the next call */
105 silk_memcpy( S->sFIR.i16, &buf[ nSamplesIn << 1 ], RESAMPLER_ORDER_FIR_12 * sizeof( opus_int16 ) );
106 RESTORE_STACK;
107 }
108