1 /* ------------------------------------------------------------------ 2 * Copyright (C) 1998-2009 PacketVideo 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either 13 * express or implied. 14 * See the License for the specific language governing permissions 15 * and limitations under the License. 16 * ------------------------------------------------------------------- 17 */ 18 /* 19 20 Filename: dst16.c 21 22 ------------------------------------------------------------------------------ 23 REVISION HISTORY 24 25 26 Who: Date: MM/DD/YYYY 27 Description: 28 29 ------------------------------------------------------------------------------ 30 INPUT AND OUTPUT DEFINITIONS 31 32 Int32 x 32-bit integer input length 16 33 34 35 ------------------------------------------------------------------------------ 36 FUNCTION DESCRIPTION 37 38 Implement discrete sine transform of lenght 16 39 40 ------------------------------------------------------------------------------ 41 REQUIREMENTS 42 43 44 ------------------------------------------------------------------------------ 45 REFERENCES 46 47 ------------------------------------------------------------------------------ 48 PSEUDO-CODE 49 50 ------------------------------------------------------------------------------ 51 */ 52 53 54 /*---------------------------------------------------------------------------- 55 ; INCLUDES 56 ----------------------------------------------------------------------------*/ 57 58 #ifdef AAC_PLUS 59 60 #include "dst16.h" 61 #include "dst8.h" 62 #include "fxp_mul32.h" 63 64 /*---------------------------------------------------------------------------- 65 ; MACROS 66 ; Define module specific macros here 67 ----------------------------------------------------------------------------*/ 68 69 70 /*---------------------------------------------------------------------------- 71 ; DEFINES 72 ; Include all pre-processor statements here. Include conditional 73 ; compile variables also. 74 ----------------------------------------------------------------------------*/ 75 76 77 #define R_SHIFT 28 78 #define Qfmt(x) (Int32)(x*((Int32)1<<R_SHIFT) + (x>=0?0.5F:-0.5F)) 79 80 const Int32 CosTable_8[8] = 81 { 82 Qfmt(0.50241928618816F), Qfmt(0.52249861493969F), 83 Qfmt(0.56694403481636F), Qfmt(0.64682178335999F), 84 Qfmt(0.78815462345125F), Qfmt(1.06067768599035F), 85 Qfmt(1.72244709823833F), Qfmt(5.10114861868916F) 86 }; 87 88 /*---------------------------------------------------------------------------- 89 ; LOCAL FUNCTION DEFINITIONS 90 ; Function Prototype declaration 91 ----------------------------------------------------------------------------*/ 92 93 /*---------------------------------------------------------------------------- 94 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS 95 ; Variable declaration - defined here and used outside this module 96 ----------------------------------------------------------------------------*/ 97 98 /*---------------------------------------------------------------------------- 99 ; EXTERNAL FUNCTION REFERENCES 100 ; Declare functions defined elsewhere and referenced in this module 101 ----------------------------------------------------------------------------*/ 102 103 /*---------------------------------------------------------------------------- 104 ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES 105 ; Declare variables used in this module but defined elsewhere 106 ----------------------------------------------------------------------------*/ 107 108 /*---------------------------------------------------------------------------- 109 ; FUNCTION CODE 110 ----------------------------------------------------------------------------*/ 111 112 113 void dst_16(Int32 vec[], Int32 scratch_mem[]) /* scratch_mem size 8 */ 114 { 115 Int32 *temp_even = scratch_mem; 116 117 Int i; 118 const Int32 *pt_cos = &CosTable_8[7]; 119 Int32 tmp0 = vec[15] >> 1; 120 Int32 tmp1, tmp2; 121 Int32 *pt_even = temp_even; 122 Int32 *pt_odd = vec; 123 Int32 *pt_vec = vec; 124 Int32 *pt_vecN_1; 125 Int32 tmp3; 126 127 128 *(pt_even++) = *(pt_vec++); 129 tmp1 = *(pt_vec++); 130 *(pt_odd++) = tmp1; 131 132 for (i = 3; i != 0; i--) 133 { 134 *(pt_even++) = *(pt_vec++); 135 tmp2 = *(pt_vec++); 136 *(pt_even++) = *(pt_vec++); 137 tmp3 = *(pt_vec++); 138 *(pt_odd++) = tmp2 + tmp1; 139 *(pt_odd++) = tmp3 + tmp2; 140 tmp1 = tmp3; 141 142 } 143 144 *(pt_even) = *(pt_vec++); 145 *(pt_odd++) = *(pt_vec) + tmp1; 146 147 148 dst_8(temp_even); 149 dst_8(vec); 150 151 pt_vec = &vec[7]; 152 153 pt_even = &temp_even[7]; 154 pt_vecN_1 = &vec[8]; 155 156 tmp1 = *(pt_even--); 157 158 for (i = 4; i != 0; i--) 159 { 160 tmp3 = fxp_mul32_Q28((*(pt_vec) - tmp0), *(pt_cos--)); 161 tmp2 = *(pt_even--); 162 *(pt_vec--) = tmp3 + tmp1; 163 *(pt_vecN_1++) = tmp3 - tmp1; 164 tmp3 = fxp_mul32_Q28((*(pt_vec) + tmp0), *(pt_cos--)); 165 tmp1 = *(pt_even--); 166 *(pt_vecN_1++) = tmp3 - tmp2; 167 *(pt_vec--) = tmp3 + tmp2; 168 } 169 170 } 171 172 #endif 173
