Vignesh Venkatasubramanian | 2bd8b54 | 2014-02-20 10:50:35 -0800 | [diff] [blame] | 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 | /* Insertion sort (fast for already almost sorted arrays): */ |
| 33 | /* Best case: O(n) for an already sorted array */ |
| 34 | /* Worst case: O(n^2) for an inversely sorted array */ |
| 35 | /* */ |
| 36 | /* Shell short: http://en.wikipedia.org/wiki/Shell_sort */ |
| 37 | |
| 38 | #include "SigProc_FIX.h" |
| 39 | |
| 40 | void silk_insertion_sort_increasing( |
| 41 | opus_int32 *a, /* I/O Unsorted / Sorted vector */ |
| 42 | opus_int *idx, /* O Index vector for the sorted elements */ |
| 43 | const opus_int L, /* I Vector length */ |
| 44 | const opus_int K /* I Number of correctly sorted positions */ |
| 45 | ) |
| 46 | { |
| 47 | opus_int32 value; |
| 48 | opus_int i, j; |
| 49 | |
| 50 | /* Safety checks */ |
| 51 | silk_assert( K > 0 ); |
| 52 | silk_assert( L > 0 ); |
| 53 | silk_assert( L >= K ); |
| 54 | |
| 55 | /* Write start indices in index vector */ |
| 56 | for( i = 0; i < K; i++ ) { |
| 57 | idx[ i ] = i; |
| 58 | } |
| 59 | |
| 60 | /* Sort vector elements by value, increasing order */ |
| 61 | for( i = 1; i < K; i++ ) { |
| 62 | value = a[ i ]; |
| 63 | for( j = i - 1; ( j >= 0 ) && ( value < a[ j ] ); j-- ) { |
| 64 | a[ j + 1 ] = a[ j ]; /* Shift value */ |
| 65 | idx[ j + 1 ] = idx[ j ]; /* Shift index */ |
| 66 | } |
| 67 | a[ j + 1 ] = value; /* Write value */ |
| 68 | idx[ j + 1 ] = i; /* Write index */ |
| 69 | } |
| 70 | |
| 71 | /* If less than L values are asked for, check the remaining values, */ |
| 72 | /* but only spend CPU to ensure that the K first values are correct */ |
| 73 | for( i = K; i < L; i++ ) { |
| 74 | value = a[ i ]; |
| 75 | if( value < a[ K - 1 ] ) { |
| 76 | for( j = K - 2; ( j >= 0 ) && ( value < a[ j ] ); j-- ) { |
| 77 | a[ j + 1 ] = a[ j ]; /* Shift value */ |
| 78 | idx[ j + 1 ] = idx[ j ]; /* Shift index */ |
| 79 | } |
| 80 | a[ j + 1 ] = value; /* Write value */ |
| 81 | idx[ j + 1 ] = i; /* Write index */ |
| 82 | } |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | #ifdef FIXED_POINT |
| 87 | /* This function is only used by the fixed-point build */ |
| 88 | void silk_insertion_sort_decreasing_int16( |
| 89 | opus_int16 *a, /* I/O Unsorted / Sorted vector */ |
| 90 | opus_int *idx, /* O Index vector for the sorted elements */ |
| 91 | const opus_int L, /* I Vector length */ |
| 92 | const opus_int K /* I Number of correctly sorted positions */ |
| 93 | ) |
| 94 | { |
| 95 | opus_int i, j; |
| 96 | opus_int value; |
| 97 | |
| 98 | /* Safety checks */ |
| 99 | silk_assert( K > 0 ); |
| 100 | silk_assert( L > 0 ); |
| 101 | silk_assert( L >= K ); |
| 102 | |
| 103 | /* Write start indices in index vector */ |
| 104 | for( i = 0; i < K; i++ ) { |
| 105 | idx[ i ] = i; |
| 106 | } |
| 107 | |
| 108 | /* Sort vector elements by value, decreasing order */ |
| 109 | for( i = 1; i < K; i++ ) { |
| 110 | value = a[ i ]; |
| 111 | for( j = i - 1; ( j >= 0 ) && ( value > a[ j ] ); j-- ) { |
| 112 | a[ j + 1 ] = a[ j ]; /* Shift value */ |
| 113 | idx[ j + 1 ] = idx[ j ]; /* Shift index */ |
| 114 | } |
| 115 | a[ j + 1 ] = value; /* Write value */ |
| 116 | idx[ j + 1 ] = i; /* Write index */ |
| 117 | } |
| 118 | |
| 119 | /* If less than L values are asked for, check the remaining values, */ |
| 120 | /* but only spend CPU to ensure that the K first values are correct */ |
| 121 | for( i = K; i < L; i++ ) { |
| 122 | value = a[ i ]; |
| 123 | if( value > a[ K - 1 ] ) { |
| 124 | for( j = K - 2; ( j >= 0 ) && ( value > a[ j ] ); j-- ) { |
| 125 | a[ j + 1 ] = a[ j ]; /* Shift value */ |
| 126 | idx[ j + 1 ] = idx[ j ]; /* Shift index */ |
| 127 | } |
| 128 | a[ j + 1 ] = value; /* Write value */ |
| 129 | idx[ j + 1 ] = i; /* Write index */ |
| 130 | } |
| 131 | } |
| 132 | } |
| 133 | #endif |
| 134 | |
| 135 | void silk_insertion_sort_increasing_all_values_int16( |
| 136 | opus_int16 *a, /* I/O Unsorted / Sorted vector */ |
| 137 | const opus_int L /* I Vector length */ |
| 138 | ) |
| 139 | { |
| 140 | opus_int value; |
| 141 | opus_int i, j; |
| 142 | |
| 143 | /* Safety checks */ |
| 144 | silk_assert( L > 0 ); |
| 145 | |
| 146 | /* Sort vector elements by value, increasing order */ |
| 147 | for( i = 1; i < L; i++ ) { |
| 148 | value = a[ i ]; |
| 149 | for( j = i - 1; ( j >= 0 ) && ( value < a[ j ] ); j-- ) { |
| 150 | a[ j + 1 ] = a[ j ]; /* Shift value */ |
| 151 | } |
| 152 | a[ j + 1 ] = value; /* Write value */ |
| 153 | } |
| 154 | } |