1/* 2 * H.264 IDCT 3 * Copyright (c) 2004-2011 Michael Niedermayer <michaelni@gmx.at> 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22/** 23 * @file 24 * H.264 IDCT. 25 * @author Michael Niedermayer <michaelni@gmx.at> 26 */ 27 28#include "bit_depth_template.c" 29#include "libavutil/common.h" 30#include "h264.h" 31#include "h264idct.h" 32 33void FUNCC(ff_h264_idct_add)(uint8_t *_dst, int16_t *_block, int stride) 34{ 35 int i; 36 pixel *dst = (pixel*)_dst; 37 dctcoef *block = (dctcoef*)_block; 38 stride >>= sizeof(pixel)-1; 39 40 block[0] += 1 << 5; 41 42 for(i=0; i<4; i++){ 43 const int z0= block[i + 4*0] + block[i + 4*2]; 44 const int z1= block[i + 4*0] - block[i + 4*2]; 45 const int z2= (block[i + 4*1]>>1) - block[i + 4*3]; 46 const int z3= block[i + 4*1] + (block[i + 4*3]>>1); 47 48 block[i + 4*0]= z0 + z3; 49 block[i + 4*1]= z1 + z2; 50 block[i + 4*2]= z1 - z2; 51 block[i + 4*3]= z0 - z3; 52 } 53 54 for(i=0; i<4; i++){ 55 const int z0= block[0 + 4*i] + block[2 + 4*i]; 56 const int z1= block[0 + 4*i] - block[2 + 4*i]; 57 const int z2= (block[1 + 4*i]>>1) - block[3 + 4*i]; 58 const int z3= block[1 + 4*i] + (block[3 + 4*i]>>1); 59 60 dst[i + 0*stride]= av_clip_pixel(dst[i + 0*stride] + ((z0 + z3) >> 6)); 61 dst[i + 1*stride]= av_clip_pixel(dst[i + 1*stride] + ((z1 + z2) >> 6)); 62 dst[i + 2*stride]= av_clip_pixel(dst[i + 2*stride] + ((z1 - z2) >> 6)); 63 dst[i + 3*stride]= av_clip_pixel(dst[i + 3*stride] + ((z0 - z3) >> 6)); 64 } 65 66 memset(block, 0, 16 * sizeof(dctcoef)); 67} 68 69void FUNCC(ff_h264_idct8_add)(uint8_t *_dst, int16_t *_block, int stride){ 70 int i; 71 pixel *dst = (pixel*)_dst; 72 dctcoef *block = (dctcoef*)_block; 73 stride >>= sizeof(pixel)-1; 74 75 block[0] += 32; 76 77 for( i = 0; i < 8; i++ ) 78 { 79 const int a0 = block[i+0*8] + block[i+4*8]; 80 const int a2 = block[i+0*8] - block[i+4*8]; 81 const int a4 = (block[i+2*8]>>1) - block[i+6*8]; 82 const int a6 = (block[i+6*8]>>1) + block[i+2*8]; 83 84 const int b0 = a0 + a6; 85 const int b2 = a2 + a4; 86 const int b4 = a2 - a4; 87 const int b6 = a0 - a6; 88 89 const int a1 = -block[i+3*8] + block[i+5*8] - block[i+7*8] - (block[i+7*8]>>1); 90 const int a3 = block[i+1*8] + block[i+7*8] - block[i+3*8] - (block[i+3*8]>>1); 91 const int a5 = -block[i+1*8] + block[i+7*8] + block[i+5*8] + (block[i+5*8]>>1); 92 const int a7 = block[i+3*8] + block[i+5*8] + block[i+1*8] + (block[i+1*8]>>1); 93 94 const int b1 = (a7>>2) + a1; 95 const int b3 = a3 + (a5>>2); 96 const int b5 = (a3>>2) - a5; 97 const int b7 = a7 - (a1>>2); 98 99 block[i+0*8] = b0 + b7; 100 block[i+7*8] = b0 - b7; 101 block[i+1*8] = b2 + b5; 102 block[i+6*8] = b2 - b5; 103 block[i+2*8] = b4 + b3; 104 block[i+5*8] = b4 - b3; 105 block[i+3*8] = b6 + b1; 106 block[i+4*8] = b6 - b1; 107 } 108 for( i = 0; i < 8; i++ ) 109 { 110 const int a0 = block[0+i*8] + block[4+i*8]; 111 const int a2 = block[0+i*8] - block[4+i*8]; 112 const int a4 = (block[2+i*8]>>1) - block[6+i*8]; 113 const int a6 = (block[6+i*8]>>1) + block[2+i*8]; 114 115 const int b0 = a0 + a6; 116 const int b2 = a2 + a4; 117 const int b4 = a2 - a4; 118 const int b6 = a0 - a6; 119 120 const int a1 = -block[3+i*8] + block[5+i*8] - block[7+i*8] - (block[7+i*8]>>1); 121 const int a3 = block[1+i*8] + block[7+i*8] - block[3+i*8] - (block[3+i*8]>>1); 122 const int a5 = -block[1+i*8] + block[7+i*8] + block[5+i*8] + (block[5+i*8]>>1); 123 const int a7 = block[3+i*8] + block[5+i*8] + block[1+i*8] + (block[1+i*8]>>1); 124 125 const int b1 = (a7>>2) + a1; 126 const int b3 = a3 + (a5>>2); 127 const int b5 = (a3>>2) - a5; 128 const int b7 = a7 - (a1>>2); 129 130 dst[i + 0*stride] = av_clip_pixel( dst[i + 0*stride] + ((b0 + b7) >> 6) ); 131 dst[i + 1*stride] = av_clip_pixel( dst[i + 1*stride] + ((b2 + b5) >> 6) ); 132 dst[i + 2*stride] = av_clip_pixel( dst[i + 2*stride] + ((b4 + b3) >> 6) ); 133 dst[i + 3*stride] = av_clip_pixel( dst[i + 3*stride] + ((b6 + b1) >> 6) ); 134 dst[i + 4*stride] = av_clip_pixel( dst[i + 4*stride] + ((b6 - b1) >> 6) ); 135 dst[i + 5*stride] = av_clip_pixel( dst[i + 5*stride] + ((b4 - b3) >> 6) ); 136 dst[i + 6*stride] = av_clip_pixel( dst[i + 6*stride] + ((b2 - b5) >> 6) ); 137 dst[i + 7*stride] = av_clip_pixel( dst[i + 7*stride] + ((b0 - b7) >> 6) ); 138 } 139 140 memset(block, 0, 64 * sizeof(dctcoef)); 141} 142 143// assumes all AC coefs are 0 144void FUNCC(ff_h264_idct_dc_add)(uint8_t *_dst, int16_t *_block, int stride){ 145 int i, j; 146 pixel *dst = (pixel*)_dst; 147 dctcoef *block = (dctcoef*)_block; 148 int dc = (block[0] + 32) >> 6; 149 stride /= sizeof(pixel); 150 block[0] = 0; 151 for( j = 0; j < 4; j++ ) 152 { 153 for( i = 0; i < 4; i++ ) 154 dst[i] = av_clip_pixel( dst[i] + dc ); 155 dst += stride; 156 } 157} 158 159void FUNCC(ff_h264_idct8_dc_add)(uint8_t *_dst, int16_t *_block, int stride){ 160 int i, j; 161 pixel *dst = (pixel*)_dst; 162 dctcoef *block = (dctcoef*)_block; 163 int dc = (block[0] + 32) >> 6; 164 block[0] = 0; 165 stride /= sizeof(pixel); 166 for( j = 0; j < 8; j++ ) 167 { 168 for( i = 0; i < 8; i++ ) 169 dst[i] = av_clip_pixel( dst[i] + dc ); 170 dst += stride; 171 } 172} 173 174void FUNCC(ff_h264_idct_add16)(uint8_t *dst, const int *block_offset, int16_t *block, int stride, const uint8_t nnzc[15*8]){ 175 int i; 176 for(i=0; i<16; i++){ 177 int nnz = nnzc[ scan8[i] ]; 178 if(nnz){ 179 if(nnz==1 && ((dctcoef*)block)[i*16]) FUNCC(ff_h264_idct_dc_add)(dst + block_offset[i], block + i*16*sizeof(pixel), stride); 180 else FUNCC(ff_h264_idct_add )(dst + block_offset[i], block + i*16*sizeof(pixel), stride); 181 } 182 } 183} 184 185void FUNCC(ff_h264_idct_add16intra)(uint8_t *dst, const int *block_offset, int16_t *block, int stride, const uint8_t nnzc[15*8]){ 186 int i; 187 for(i=0; i<16; i++){ 188 if(nnzc[ scan8[i] ]) FUNCC(ff_h264_idct_add )(dst + block_offset[i], block + i*16*sizeof(pixel), stride); 189 else if(((dctcoef*)block)[i*16]) FUNCC(ff_h264_idct_dc_add)(dst + block_offset[i], block + i*16*sizeof(pixel), stride); 190 } 191} 192 193void FUNCC(ff_h264_idct8_add4)(uint8_t *dst, const int *block_offset, int16_t *block, int stride, const uint8_t nnzc[15*8]){ 194 int i; 195 for(i=0; i<16; i+=4){ 196 int nnz = nnzc[ scan8[i] ]; 197 if(nnz){ 198 if(nnz==1 && ((dctcoef*)block)[i*16]) FUNCC(ff_h264_idct8_dc_add)(dst + block_offset[i], block + i*16*sizeof(pixel), stride); 199 else FUNCC(ff_h264_idct8_add )(dst + block_offset[i], block + i*16*sizeof(pixel), stride); 200 } 201 } 202} 203 204void FUNCC(ff_h264_idct_add8)(uint8_t **dest, const int *block_offset, int16_t *block, int stride, const uint8_t nnzc[15*8]){ 205 int i, j; 206 for(j=1; j<3; j++){ 207 for(i=j*16; i<j*16+4; i++){ 208 if(nnzc[ scan8[i] ]) 209 FUNCC(ff_h264_idct_add )(dest[j-1] + block_offset[i], block + i*16*sizeof(pixel), stride); 210 else if(((dctcoef*)block)[i*16]) 211 FUNCC(ff_h264_idct_dc_add)(dest[j-1] + block_offset[i], block + i*16*sizeof(pixel), stride); 212 } 213 } 214} 215 216void FUNCC(ff_h264_idct_add8_422)(uint8_t **dest, const int *block_offset, int16_t *block, int stride, const uint8_t nnzc[15*8]){ 217 int i, j; 218 219 for(j=1; j<3; j++){ 220 for(i=j*16; i<j*16+4; i++){ 221 if(nnzc[ scan8[i] ]) 222 FUNCC(ff_h264_idct_add )(dest[j-1] + block_offset[i], block + i*16*sizeof(pixel), stride); 223 else if(((dctcoef*)block)[i*16]) 224 FUNCC(ff_h264_idct_dc_add)(dest[j-1] + block_offset[i], block + i*16*sizeof(pixel), stride); 225 } 226 } 227 228 for(j=1; j<3; j++){ 229 for(i=j*16+4; i<j*16+8; i++){ 230 if(nnzc[ scan8[i+4] ]) 231 FUNCC(ff_h264_idct_add )(dest[j-1] + block_offset[i+4], block + i*16*sizeof(pixel), stride); 232 else if(((dctcoef*)block)[i*16]) 233 FUNCC(ff_h264_idct_dc_add)(dest[j-1] + block_offset[i+4], block + i*16*sizeof(pixel), stride); 234 } 235 } 236} 237 238/** 239 * IDCT transforms the 16 dc values and dequantizes them. 240 * @param qmul quantization parameter 241 */ 242void FUNCC(ff_h264_luma_dc_dequant_idct)(int16_t *_output, int16_t *_input, int qmul){ 243#define stride 16 244 int i; 245 int temp[16]; 246 static const uint8_t x_offset[4]={0, 2*stride, 8*stride, 10*stride}; 247 dctcoef *input = (dctcoef*)_input; 248 dctcoef *output = (dctcoef*)_output; 249 250 for(i=0; i<4; i++){ 251 const int z0= input[4*i+0] + input[4*i+1]; 252 const int z1= input[4*i+0] - input[4*i+1]; 253 const int z2= input[4*i+2] - input[4*i+3]; 254 const int z3= input[4*i+2] + input[4*i+3]; 255 256 temp[4*i+0]= z0+z3; 257 temp[4*i+1]= z0-z3; 258 temp[4*i+2]= z1-z2; 259 temp[4*i+3]= z1+z2; 260 } 261 262 for(i=0; i<4; i++){ 263 const int offset= x_offset[i]; 264 const int z0= temp[4*0+i] + temp[4*2+i]; 265 const int z1= temp[4*0+i] - temp[4*2+i]; 266 const int z2= temp[4*1+i] - temp[4*3+i]; 267 const int z3= temp[4*1+i] + temp[4*3+i]; 268 269 output[stride* 0+offset]= ((((z0 + z3)*qmul + 128 ) >> 8)); 270 output[stride* 1+offset]= ((((z1 + z2)*qmul + 128 ) >> 8)); 271 output[stride* 4+offset]= ((((z1 - z2)*qmul + 128 ) >> 8)); 272 output[stride* 5+offset]= ((((z0 - z3)*qmul + 128 ) >> 8)); 273 } 274#undef stride 275} 276 277void FUNCC(ff_h264_chroma422_dc_dequant_idct)(int16_t *_block, int qmul){ 278 const int stride= 16*2; 279 const int xStride= 16; 280 int i; 281 int temp[8]; 282 static const uint8_t x_offset[2]={0, 16}; 283 dctcoef *block = (dctcoef*)_block; 284 285 for(i=0; i<4; i++){ 286 temp[2*i+0] = block[stride*i + xStride*0] + block[stride*i + xStride*1]; 287 temp[2*i+1] = block[stride*i + xStride*0] - block[stride*i + xStride*1]; 288 } 289 290 for(i=0; i<2; i++){ 291 const int offset= x_offset[i]; 292 const int z0= temp[2*0+i] + temp[2*2+i]; 293 const int z1= temp[2*0+i] - temp[2*2+i]; 294 const int z2= temp[2*1+i] - temp[2*3+i]; 295 const int z3= temp[2*1+i] + temp[2*3+i]; 296 297 block[stride*0+offset]= ((z0 + z3)*qmul + 128) >> 8; 298 block[stride*1+offset]= ((z1 + z2)*qmul + 128) >> 8; 299 block[stride*2+offset]= ((z1 - z2)*qmul + 128) >> 8; 300 block[stride*3+offset]= ((z0 - z3)*qmul + 128) >> 8; 301 } 302} 303 304void FUNCC(ff_h264_chroma_dc_dequant_idct)(int16_t *_block, int qmul){ 305 const int stride= 16*2; 306 const int xStride= 16; 307 int a,b,c,d,e; 308 dctcoef *block = (dctcoef*)_block; 309 310 a= block[stride*0 + xStride*0]; 311 b= block[stride*0 + xStride*1]; 312 c= block[stride*1 + xStride*0]; 313 d= block[stride*1 + xStride*1]; 314 315 e= a-b; 316 a= a+b; 317 b= c-d; 318 c= c+d; 319 320 block[stride*0 + xStride*0]= ((a+c)*qmul) >> 7; 321 block[stride*0 + xStride*1]= ((e+b)*qmul) >> 7; 322 block[stride*1 + xStride*0]= ((a-c)*qmul) >> 7; 323 block[stride*1 + xStride*1]= ((e-b)*qmul) >> 7; 324} 325