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 "main.h" 33 34 /* shell coder; pulse-subframe length is hardcoded */ 35 36 static inline void combine_pulses( 37 opus_int *out, /* O combined pulses vector [len] */ 38 const opus_int *in, /* I input vector [2 * len] */ 39 const opus_int len /* I number of OUTPUT samples */ 40 ) 41 { 42 opus_int k; 43 for( k = 0; k < len; k++ ) { 44 out[ k ] = in[ 2 * k ] + in[ 2 * k + 1 ]; 45 } 46 } 47 48 static inline void encode_split( 49 ec_enc *psRangeEnc, /* I/O compressor data structure */ 50 const opus_int p_child1, /* I pulse amplitude of first child subframe */ 51 const opus_int p, /* I pulse amplitude of current subframe */ 52 const opus_uint8 *shell_table /* I table of shell cdfs */ 53 ) 54 { 55 if( p > 0 ) { 56 ec_enc_icdf( psRangeEnc, p_child1, &shell_table[ silk_shell_code_table_offsets[ p ] ], 8 ); 57 } 58 } 59 60 static inline void decode_split( 61 opus_int *p_child1, /* O pulse amplitude of first child subframe */ 62 opus_int *p_child2, /* O pulse amplitude of second child subframe */ 63 ec_dec *psRangeDec, /* I/O Compressor data structure */ 64 const opus_int p, /* I pulse amplitude of current subframe */ 65 const opus_uint8 *shell_table /* I table of shell cdfs */ 66 ) 67 { 68 if( p > 0 ) { 69 p_child1[ 0 ] = ec_dec_icdf( psRangeDec, &shell_table[ silk_shell_code_table_offsets[ p ] ], 8 ); 70 p_child2[ 0 ] = p - p_child1[ 0 ]; 71 } else { 72 p_child1[ 0 ] = 0; 73 p_child2[ 0 ] = 0; 74 } 75 } 76 77 /* Shell encoder, operates on one shell code frame of 16 pulses */ 78 void silk_shell_encoder( 79 ec_enc *psRangeEnc, /* I/O compressor data structure */ 80 const opus_int *pulses0 /* I data: nonnegative pulse amplitudes */ 81 ) 82 { 83 opus_int pulses1[ 8 ], pulses2[ 4 ], pulses3[ 2 ], pulses4[ 1 ]; 84 85 /* this function operates on one shell code frame of 16 pulses */ 86 silk_assert( SHELL_CODEC_FRAME_LENGTH == 16 ); 87 88 /* tree representation per pulse-subframe */ 89 combine_pulses( pulses1, pulses0, 8 ); 90 combine_pulses( pulses2, pulses1, 4 ); 91 combine_pulses( pulses3, pulses2, 2 ); 92 combine_pulses( pulses4, pulses3, 1 ); 93 94 encode_split( psRangeEnc, pulses3[ 0 ], pulses4[ 0 ], silk_shell_code_table3 ); 95 96 encode_split( psRangeEnc, pulses2[ 0 ], pulses3[ 0 ], silk_shell_code_table2 ); 97 98 encode_split( psRangeEnc, pulses1[ 0 ], pulses2[ 0 ], silk_shell_code_table1 ); 99 encode_split( psRangeEnc, pulses0[ 0 ], pulses1[ 0 ], silk_shell_code_table0 ); 100 encode_split( psRangeEnc, pulses0[ 2 ], pulses1[ 1 ], silk_shell_code_table0 ); 101 102 encode_split( psRangeEnc, pulses1[ 2 ], pulses2[ 1 ], silk_shell_code_table1 ); 103 encode_split( psRangeEnc, pulses0[ 4 ], pulses1[ 2 ], silk_shell_code_table0 ); 104 encode_split( psRangeEnc, pulses0[ 6 ], pulses1[ 3 ], silk_shell_code_table0 ); 105 106 encode_split( psRangeEnc, pulses2[ 2 ], pulses3[ 1 ], silk_shell_code_table2 ); 107 108 encode_split( psRangeEnc, pulses1[ 4 ], pulses2[ 2 ], silk_shell_code_table1 ); 109 encode_split( psRangeEnc, pulses0[ 8 ], pulses1[ 4 ], silk_shell_code_table0 ); 110 encode_split( psRangeEnc, pulses0[ 10 ], pulses1[ 5 ], silk_shell_code_table0 ); 111 112 encode_split( psRangeEnc, pulses1[ 6 ], pulses2[ 3 ], silk_shell_code_table1 ); 113 encode_split( psRangeEnc, pulses0[ 12 ], pulses1[ 6 ], silk_shell_code_table0 ); 114 encode_split( psRangeEnc, pulses0[ 14 ], pulses1[ 7 ], silk_shell_code_table0 ); 115 } 116 117 118 /* Shell decoder, operates on one shell code frame of 16 pulses */ 119 void silk_shell_decoder( 120 opus_int *pulses0, /* O data: nonnegative pulse amplitudes */ 121 ec_dec *psRangeDec, /* I/O Compressor data structure */ 122 const opus_int pulses4 /* I number of pulses per pulse-subframe */ 123 ) 124 { 125 opus_int pulses3[ 2 ], pulses2[ 4 ], pulses1[ 8 ]; 126 127 /* this function operates on one shell code frame of 16 pulses */ 128 silk_assert( SHELL_CODEC_FRAME_LENGTH == 16 ); 129 130 decode_split( &pulses3[ 0 ], &pulses3[ 1 ], psRangeDec, pulses4, silk_shell_code_table3 ); 131 132 decode_split( &pulses2[ 0 ], &pulses2[ 1 ], psRangeDec, pulses3[ 0 ], silk_shell_code_table2 ); 133 134 decode_split( &pulses1[ 0 ], &pulses1[ 1 ], psRangeDec, pulses2[ 0 ], silk_shell_code_table1 ); 135 decode_split( &pulses0[ 0 ], &pulses0[ 1 ], psRangeDec, pulses1[ 0 ], silk_shell_code_table0 ); 136 decode_split( &pulses0[ 2 ], &pulses0[ 3 ], psRangeDec, pulses1[ 1 ], silk_shell_code_table0 ); 137 138 decode_split( &pulses1[ 2 ], &pulses1[ 3 ], psRangeDec, pulses2[ 1 ], silk_shell_code_table1 ); 139 decode_split( &pulses0[ 4 ], &pulses0[ 5 ], psRangeDec, pulses1[ 2 ], silk_shell_code_table0 ); 140 decode_split( &pulses0[ 6 ], &pulses0[ 7 ], psRangeDec, pulses1[ 3 ], silk_shell_code_table0 ); 141 142 decode_split( &pulses2[ 2 ], &pulses2[ 3 ], psRangeDec, pulses3[ 1 ], silk_shell_code_table2 ); 143 144 decode_split( &pulses1[ 4 ], &pulses1[ 5 ], psRangeDec, pulses2[ 2 ], silk_shell_code_table1 ); 145 decode_split( &pulses0[ 8 ], &pulses0[ 9 ], psRangeDec, pulses1[ 4 ], silk_shell_code_table0 ); 146 decode_split( &pulses0[ 10 ], &pulses0[ 11 ], psRangeDec, pulses1[ 5 ], silk_shell_code_table0 ); 147 148 decode_split( &pulses1[ 6 ], &pulses1[ 7 ], psRangeDec, pulses2[ 3 ], silk_shell_code_table1 ); 149 decode_split( &pulses0[ 12 ], &pulses0[ 13 ], psRangeDec, pulses1[ 6 ], silk_shell_code_table0 ); 150 decode_split( &pulses0[ 14 ], &pulses0[ 15 ], psRangeDec, pulses1[ 7 ], silk_shell_code_table0 ); 151 } 152
