1/* 2 * Simple IDCT 3 * 4 * Copyright (c) 2001 Michael Niedermayer <michaelni@gmx.at> 5 * 6 * This file is part of Libav. 7 * 8 * Libav is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU Lesser General Public 10 * License as published by the Free Software Foundation; either 11 * version 2.1 of the License, or (at your option) any later version. 12 * 13 * Libav is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * Lesser General Public License for more details. 17 * 18 * You should have received a copy of the GNU Lesser General Public 19 * License along with Libav; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 */ 22 23/** 24 * @file 25 * simpleidct in C. 26 */ 27 28/* 29 based upon some outcommented c code from mpeg2dec (idct_mmx.c 30 written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>) 31 */ 32 33#include "bit_depth_template.c" 34 35#undef W1 36#undef W2 37#undef W3 38#undef W4 39#undef W5 40#undef W6 41#undef W7 42#undef ROW_SHIFT 43#undef COL_SHIFT 44#undef DC_SHIFT 45#undef MUL 46#undef MAC 47 48#if BIT_DEPTH == 8 49 50#define W1 22725 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 51#define W2 21407 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 52#define W3 19266 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 53#define W4 16383 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 54#define W5 12873 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 55#define W6 8867 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 56#define W7 4520 //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5 57 58#define ROW_SHIFT 11 59#define COL_SHIFT 20 60#define DC_SHIFT 3 61 62#define MUL(a, b) MUL16(a, b) 63#define MAC(a, b, c) MAC16(a, b, c) 64 65#elif BIT_DEPTH == 10 66 67#define W1 90901 68#define W2 85627 69#define W3 77062 70#define W4 65535 71#define W5 51491 72#define W6 35468 73#define W7 18081 74 75#define ROW_SHIFT 15 76#define COL_SHIFT 20 77#define DC_SHIFT 1 78 79#define MUL(a, b) ((a) * (b)) 80#define MAC(a, b, c) ((a) += (b) * (c)) 81 82#else 83 84#error "Unsupported bitdepth" 85 86#endif 87 88static inline void FUNC(idctRowCondDC)(DCTELEM *row, int extra_shift) 89{ 90 int a0, a1, a2, a3, b0, b1, b2, b3; 91 92#if HAVE_FAST_64BIT 93#define ROW0_MASK (0xffffLL << 48 * HAVE_BIGENDIAN) 94 if (((((uint64_t *)row)[0] & ~ROW0_MASK) | ((uint64_t *)row)[1]) == 0) { 95 uint64_t temp; 96 if (DC_SHIFT - extra_shift > 0) { 97 temp = (row[0] << (DC_SHIFT - extra_shift)) & 0xffff; 98 } else { 99 temp = (row[0] >> (extra_shift - DC_SHIFT)) & 0xffff; 100 } 101 temp += temp << 16; 102 temp += temp << 32; 103 ((uint64_t *)row)[0] = temp; 104 ((uint64_t *)row)[1] = temp; 105 return; 106 } 107#else 108 if (!(((uint32_t*)row)[1] | 109 ((uint32_t*)row)[2] | 110 ((uint32_t*)row)[3] | 111 row[1])) { 112 uint32_t temp; 113 if (DC_SHIFT - extra_shift > 0) { 114 temp = (row[0] << (DC_SHIFT - extra_shift)) & 0xffff; 115 } else { 116 temp = (row[0] >> (extra_shift - DC_SHIFT)) & 0xffff; 117 } 118 temp += temp << 16; 119 ((uint32_t*)row)[0]=((uint32_t*)row)[1] = 120 ((uint32_t*)row)[2]=((uint32_t*)row)[3] = temp; 121 return; 122 } 123#endif 124 125 a0 = (W4 * row[0]) + (1 << (ROW_SHIFT - 1)); 126 a1 = a0; 127 a2 = a0; 128 a3 = a0; 129 130 a0 += W2 * row[2]; 131 a1 += W6 * row[2]; 132 a2 -= W6 * row[2]; 133 a3 -= W2 * row[2]; 134 135 b0 = MUL(W1, row[1]); 136 MAC(b0, W3, row[3]); 137 b1 = MUL(W3, row[1]); 138 MAC(b1, -W7, row[3]); 139 b2 = MUL(W5, row[1]); 140 MAC(b2, -W1, row[3]); 141 b3 = MUL(W7, row[1]); 142 MAC(b3, -W5, row[3]); 143 144 if (AV_RN64A(row + 4)) { 145 a0 += W4*row[4] + W6*row[6]; 146 a1 += - W4*row[4] - W2*row[6]; 147 a2 += - W4*row[4] + W2*row[6]; 148 a3 += W4*row[4] - W6*row[6]; 149 150 MAC(b0, W5, row[5]); 151 MAC(b0, W7, row[7]); 152 153 MAC(b1, -W1, row[5]); 154 MAC(b1, -W5, row[7]); 155 156 MAC(b2, W7, row[5]); 157 MAC(b2, W3, row[7]); 158 159 MAC(b3, W3, row[5]); 160 MAC(b3, -W1, row[7]); 161 } 162 163 row[0] = (a0 + b0) >> (ROW_SHIFT + extra_shift); 164 row[7] = (a0 - b0) >> (ROW_SHIFT + extra_shift); 165 row[1] = (a1 + b1) >> (ROW_SHIFT + extra_shift); 166 row[6] = (a1 - b1) >> (ROW_SHIFT + extra_shift); 167 row[2] = (a2 + b2) >> (ROW_SHIFT + extra_shift); 168 row[5] = (a2 - b2) >> (ROW_SHIFT + extra_shift); 169 row[3] = (a3 + b3) >> (ROW_SHIFT + extra_shift); 170 row[4] = (a3 - b3) >> (ROW_SHIFT + extra_shift); 171} 172 173#define IDCT_COLS do { \ 174 a0 = W4 * (col[8*0] + ((1<<(COL_SHIFT-1))/W4)); \ 175 a1 = a0; \ 176 a2 = a0; \ 177 a3 = a0; \ 178 \ 179 a0 += W2*col[8*2]; \ 180 a1 += W6*col[8*2]; \ 181 a2 += -W6*col[8*2]; \ 182 a3 += -W2*col[8*2]; \ 183 \ 184 b0 = MUL(W1, col[8*1]); \ 185 b1 = MUL(W3, col[8*1]); \ 186 b2 = MUL(W5, col[8*1]); \ 187 b3 = MUL(W7, col[8*1]); \ 188 \ 189 MAC(b0, W3, col[8*3]); \ 190 MAC(b1, -W7, col[8*3]); \ 191 MAC(b2, -W1, col[8*3]); \ 192 MAC(b3, -W5, col[8*3]); \ 193 \ 194 if (col[8*4]) { \ 195 a0 += W4*col[8*4]; \ 196 a1 += -W4*col[8*4]; \ 197 a2 += -W4*col[8*4]; \ 198 a3 += W4*col[8*4]; \ 199 } \ 200 \ 201 if (col[8*5]) { \ 202 MAC(b0, W5, col[8*5]); \ 203 MAC(b1, -W1, col[8*5]); \ 204 MAC(b2, W7, col[8*5]); \ 205 MAC(b3, W3, col[8*5]); \ 206 } \ 207 \ 208 if (col[8*6]) { \ 209 a0 += W6*col[8*6]; \ 210 a1 += -W2*col[8*6]; \ 211 a2 += W2*col[8*6]; \ 212 a3 += -W6*col[8*6]; \ 213 } \ 214 \ 215 if (col[8*7]) { \ 216 MAC(b0, W7, col[8*7]); \ 217 MAC(b1, -W5, col[8*7]); \ 218 MAC(b2, W3, col[8*7]); \ 219 MAC(b3, -W1, col[8*7]); \ 220 } \ 221 } while (0) 222 223static inline void FUNC(idctSparseColPut)(pixel *dest, int line_size, 224 DCTELEM *col) 225{ 226 int a0, a1, a2, a3, b0, b1, b2, b3; 227 228 IDCT_COLS; 229 230 dest[0] = av_clip_pixel((a0 + b0) >> COL_SHIFT); 231 dest += line_size; 232 dest[0] = av_clip_pixel((a1 + b1) >> COL_SHIFT); 233 dest += line_size; 234 dest[0] = av_clip_pixel((a2 + b2) >> COL_SHIFT); 235 dest += line_size; 236 dest[0] = av_clip_pixel((a3 + b3) >> COL_SHIFT); 237 dest += line_size; 238 dest[0] = av_clip_pixel((a3 - b3) >> COL_SHIFT); 239 dest += line_size; 240 dest[0] = av_clip_pixel((a2 - b2) >> COL_SHIFT); 241 dest += line_size; 242 dest[0] = av_clip_pixel((a1 - b1) >> COL_SHIFT); 243 dest += line_size; 244 dest[0] = av_clip_pixel((a0 - b0) >> COL_SHIFT); 245} 246 247static inline void FUNC(idctSparseColAdd)(pixel *dest, int line_size, 248 DCTELEM *col) 249{ 250 int a0, a1, a2, a3, b0, b1, b2, b3; 251 252 IDCT_COLS; 253 254 dest[0] = av_clip_pixel(dest[0] + ((a0 + b0) >> COL_SHIFT)); 255 dest += line_size; 256 dest[0] = av_clip_pixel(dest[0] + ((a1 + b1) >> COL_SHIFT)); 257 dest += line_size; 258 dest[0] = av_clip_pixel(dest[0] + ((a2 + b2) >> COL_SHIFT)); 259 dest += line_size; 260 dest[0] = av_clip_pixel(dest[0] + ((a3 + b3) >> COL_SHIFT)); 261 dest += line_size; 262 dest[0] = av_clip_pixel(dest[0] + ((a3 - b3) >> COL_SHIFT)); 263 dest += line_size; 264 dest[0] = av_clip_pixel(dest[0] + ((a2 - b2) >> COL_SHIFT)); 265 dest += line_size; 266 dest[0] = av_clip_pixel(dest[0] + ((a1 - b1) >> COL_SHIFT)); 267 dest += line_size; 268 dest[0] = av_clip_pixel(dest[0] + ((a0 - b0) >> COL_SHIFT)); 269} 270 271static inline void FUNC(idctSparseCol)(DCTELEM *col) 272{ 273 int a0, a1, a2, a3, b0, b1, b2, b3; 274 275 IDCT_COLS; 276 277 col[0 ] = ((a0 + b0) >> COL_SHIFT); 278 col[8 ] = ((a1 + b1) >> COL_SHIFT); 279 col[16] = ((a2 + b2) >> COL_SHIFT); 280 col[24] = ((a3 + b3) >> COL_SHIFT); 281 col[32] = ((a3 - b3) >> COL_SHIFT); 282 col[40] = ((a2 - b2) >> COL_SHIFT); 283 col[48] = ((a1 - b1) >> COL_SHIFT); 284 col[56] = ((a0 - b0) >> COL_SHIFT); 285} 286 287void FUNC(ff_simple_idct_put)(uint8_t *dest_, int line_size, DCTELEM *block) 288{ 289 pixel *dest = (pixel *)dest_; 290 int i; 291 292 line_size /= sizeof(pixel); 293 294 for (i = 0; i < 8; i++) 295 FUNC(idctRowCondDC)(block + i*8, 0); 296 297 for (i = 0; i < 8; i++) 298 FUNC(idctSparseColPut)(dest + i, line_size, block + i); 299} 300 301void FUNC(ff_simple_idct_add)(uint8_t *dest_, int line_size, DCTELEM *block) 302{ 303 pixel *dest = (pixel *)dest_; 304 int i; 305 306 line_size /= sizeof(pixel); 307 308 for (i = 0; i < 8; i++) 309 FUNC(idctRowCondDC)(block + i*8, 0); 310 311 for (i = 0; i < 8; i++) 312 FUNC(idctSparseColAdd)(dest + i, line_size, block + i); 313} 314 315void FUNC(ff_simple_idct)(DCTELEM *block) 316{ 317 int i; 318 319 for (i = 0; i < 8; i++) 320 FUNC(idctRowCondDC)(block + i*8, 0); 321 322 for (i = 0; i < 8; i++) 323 FUNC(idctSparseCol)(block + i); 324} 325