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comparison: media/libvpx/vp8/common/idctllm.c
media/libvpx/vp8/common/idctllm.c
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| -1:000000000000 | 0:d9417399e2e6 |
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| 1 /* | |
| 2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved. | |
| 3 * | |
| 4 * Use of this source code is governed by a BSD-style license | |
| 5 * that can be found in the LICENSE file in the root of the source | |
| 6 * tree. An additional intellectual property rights grant can be found | |
| 7 * in the file PATENTS. All contributing project authors may | |
| 8 * be found in the AUTHORS file in the root of the source tree. | |
| 9 */ | |
| 10 | |
| 11 | |
| 12 /**************************************************************************** | |
| 13 * Notes: | |
| 14 * | |
| 15 * This implementation makes use of 16 bit fixed point verio of two multiply | |
| 16 * constants: | |
| 17 * 1. sqrt(2) * cos (pi/8) | |
| 18 * 2. sqrt(2) * sin (pi/8) | |
| 19 * Becuase the first constant is bigger than 1, to maintain the same 16 bit | |
| 20 * fixed point precision as the second one, we use a trick of | |
| 21 * x * a = x + x*(a-1) | |
| 22 * so | |
| 23 * x * sqrt(2) * cos (pi/8) = x + x * (sqrt(2) *cos(pi/8)-1). | |
| 24 **************************************************************************/ | |
| 25 static const int cospi8sqrt2minus1 = 20091; | |
| 26 static const int sinpi8sqrt2 = 35468; | |
| 27 | |
| 28 void vp8_short_idct4x4llm_c(short *input, unsigned char *pred_ptr, | |
| 29 int pred_stride, unsigned char *dst_ptr, | |
| 30 int dst_stride) | |
| 31 { | |
| 32 int i; | |
| 33 int r, c; | |
| 34 int a1, b1, c1, d1; | |
| 35 short output[16]; | |
| 36 short *ip = input; | |
| 37 short *op = output; | |
| 38 int temp1, temp2; | |
| 39 int shortpitch = 4; | |
| 40 | |
| 41 for (i = 0; i < 4; i++) | |
| 42 { | |
| 43 a1 = ip[0] + ip[8]; | |
| 44 b1 = ip[0] - ip[8]; | |
| 45 | |
| 46 temp1 = (ip[4] * sinpi8sqrt2) >> 16; | |
| 47 temp2 = ip[12] + ((ip[12] * cospi8sqrt2minus1) >> 16); | |
| 48 c1 = temp1 - temp2; | |
| 49 | |
| 50 temp1 = ip[4] + ((ip[4] * cospi8sqrt2minus1) >> 16); | |
| 51 temp2 = (ip[12] * sinpi8sqrt2) >> 16; | |
| 52 d1 = temp1 + temp2; | |
| 53 | |
| 54 op[shortpitch*0] = a1 + d1; | |
| 55 op[shortpitch*3] = a1 - d1; | |
| 56 | |
| 57 op[shortpitch*1] = b1 + c1; | |
| 58 op[shortpitch*2] = b1 - c1; | |
| 59 | |
| 60 ip++; | |
| 61 op++; | |
| 62 } | |
| 63 | |
| 64 ip = output; | |
| 65 op = output; | |
| 66 | |
| 67 for (i = 0; i < 4; i++) | |
| 68 { | |
| 69 a1 = ip[0] + ip[2]; | |
| 70 b1 = ip[0] - ip[2]; | |
| 71 | |
| 72 temp1 = (ip[1] * sinpi8sqrt2) >> 16; | |
| 73 temp2 = ip[3] + ((ip[3] * cospi8sqrt2minus1) >> 16); | |
| 74 c1 = temp1 - temp2; | |
| 75 | |
| 76 temp1 = ip[1] + ((ip[1] * cospi8sqrt2minus1) >> 16); | |
| 77 temp2 = (ip[3] * sinpi8sqrt2) >> 16; | |
| 78 d1 = temp1 + temp2; | |
| 79 | |
| 80 | |
| 81 op[0] = (a1 + d1 + 4) >> 3; | |
| 82 op[3] = (a1 - d1 + 4) >> 3; | |
| 83 | |
| 84 op[1] = (b1 + c1 + 4) >> 3; | |
| 85 op[2] = (b1 - c1 + 4) >> 3; | |
| 86 | |
| 87 ip += shortpitch; | |
| 88 op += shortpitch; | |
| 89 } | |
| 90 | |
| 91 ip = output; | |
| 92 for (r = 0; r < 4; r++) | |
| 93 { | |
| 94 for (c = 0; c < 4; c++) | |
| 95 { | |
| 96 int a = ip[c] + pred_ptr[c] ; | |
| 97 | |
| 98 if (a < 0) | |
| 99 a = 0; | |
| 100 | |
| 101 if (a > 255) | |
| 102 a = 255; | |
| 103 | |
| 104 dst_ptr[c] = (unsigned char) a ; | |
| 105 } | |
| 106 ip += 4; | |
| 107 dst_ptr += dst_stride; | |
| 108 pred_ptr += pred_stride; | |
| 109 } | |
| 110 } | |
| 111 | |
| 112 void vp8_dc_only_idct_add_c(short input_dc, unsigned char *pred_ptr, | |
| 113 int pred_stride, unsigned char *dst_ptr, | |
| 114 int dst_stride) | |
| 115 { | |
| 116 int a1 = ((input_dc + 4) >> 3); | |
| 117 int r, c; | |
| 118 | |
| 119 for (r = 0; r < 4; r++) | |
| 120 { | |
| 121 for (c = 0; c < 4; c++) | |
| 122 { | |
| 123 int a = a1 + pred_ptr[c] ; | |
| 124 | |
| 125 if (a < 0) | |
| 126 a = 0; | |
| 127 | |
| 128 if (a > 255) | |
| 129 a = 255; | |
| 130 | |
| 131 dst_ptr[c] = (unsigned char) a ; | |
| 132 } | |
| 133 | |
| 134 dst_ptr += dst_stride; | |
| 135 pred_ptr += pred_stride; | |
| 136 } | |
| 137 | |
| 138 } | |
| 139 | |
| 140 void vp8_short_inv_walsh4x4_c(short *input, short *mb_dqcoeff) | |
| 141 { | |
| 142 short output[16]; | |
| 143 int i; | |
| 144 int a1, b1, c1, d1; | |
| 145 int a2, b2, c2, d2; | |
| 146 short *ip = input; | |
| 147 short *op = output; | |
| 148 | |
| 149 for (i = 0; i < 4; i++) | |
| 150 { | |
| 151 a1 = ip[0] + ip[12]; | |
| 152 b1 = ip[4] + ip[8]; | |
| 153 c1 = ip[4] - ip[8]; | |
| 154 d1 = ip[0] - ip[12]; | |
| 155 | |
| 156 op[0] = a1 + b1; | |
| 157 op[4] = c1 + d1; | |
| 158 op[8] = a1 - b1; | |
| 159 op[12] = d1 - c1; | |
| 160 ip++; | |
| 161 op++; | |
| 162 } | |
| 163 | |
| 164 ip = output; | |
| 165 op = output; | |
| 166 | |
| 167 for (i = 0; i < 4; i++) | |
| 168 { | |
| 169 a1 = ip[0] + ip[3]; | |
| 170 b1 = ip[1] + ip[2]; | |
| 171 c1 = ip[1] - ip[2]; | |
| 172 d1 = ip[0] - ip[3]; | |
| 173 | |
| 174 a2 = a1 + b1; | |
| 175 b2 = c1 + d1; | |
| 176 c2 = a1 - b1; | |
| 177 d2 = d1 - c1; | |
| 178 | |
| 179 op[0] = (a2 + 3) >> 3; | |
| 180 op[1] = (b2 + 3) >> 3; | |
| 181 op[2] = (c2 + 3) >> 3; | |
| 182 op[3] = (d2 + 3) >> 3; | |
| 183 | |
| 184 ip += 4; | |
| 185 op += 4; | |
| 186 } | |
| 187 | |
| 188 for(i = 0; i < 16; i++) | |
| 189 { | |
| 190 mb_dqcoeff[i * 16] = output[i]; | |
| 191 } | |
| 192 } | |
| 193 | |
| 194 void vp8_short_inv_walsh4x4_1_c(short *input, short *mb_dqcoeff) | |
| 195 { | |
| 196 int i; | |
| 197 int a1; | |
| 198 | |
| 199 a1 = ((input[0] + 3) >> 3); | |
| 200 for(i = 0; i < 16; i++) | |
| 201 { | |
| 202 mb_dqcoeff[i * 16] = a1; | |
| 203 } | |
| 204 } |
