diff options
Diffstat (limited to 'contrib/ffmpeg/libavcodec/h264idct.c')
| -rw-r--r-- | contrib/ffmpeg/libavcodec/h264idct.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavcodec/h264idct.c b/contrib/ffmpeg/libavcodec/h264idct.c new file mode 100644 index 000000000..a6a56d33a --- /dev/null +++ b/contrib/ffmpeg/libavcodec/h264idct.c @@ -0,0 +1,168 @@ +/* + * H.264 IDCT + * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at> + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + * + */ + +/** + * @file h264-idct.c + * H.264 IDCT. + * @author Michael Niedermayer <michaelni@gmx.at> + */ + +#include "dsputil.h" + +static av_always_inline void idct_internal(uint8_t *dst, DCTELEM *block, int stride, int block_stride, int shift, int add){ + int i; + uint8_t *cm = ff_cropTbl + MAX_NEG_CROP; + + block[0] += 1<<(shift-1); + + for(i=0; i<4; i++){ + const int z0= block[0 + block_stride*i] + block[2 + block_stride*i]; + const int z1= block[0 + block_stride*i] - block[2 + block_stride*i]; + const int z2= (block[1 + block_stride*i]>>1) - block[3 + block_stride*i]; + const int z3= block[1 + block_stride*i] + (block[3 + block_stride*i]>>1); + + block[0 + block_stride*i]= z0 + z3; + block[1 + block_stride*i]= z1 + z2; + block[2 + block_stride*i]= z1 - z2; + block[3 + block_stride*i]= z0 - z3; + } + + for(i=0; i<4; i++){ + const int z0= block[i + block_stride*0] + block[i + block_stride*2]; + const int z1= block[i + block_stride*0] - block[i + block_stride*2]; + const int z2= (block[i + block_stride*1]>>1) - block[i + block_stride*3]; + const int z3= block[i + block_stride*1] + (block[i + block_stride*3]>>1); + + dst[i + 0*stride]= cm[ add*dst[i + 0*stride] + ((z0 + z3) >> shift) ]; + dst[i + 1*stride]= cm[ add*dst[i + 1*stride] + ((z1 + z2) >> shift) ]; + dst[i + 2*stride]= cm[ add*dst[i + 2*stride] + ((z1 - z2) >> shift) ]; + dst[i + 3*stride]= cm[ add*dst[i + 3*stride] + ((z0 - z3) >> shift) ]; + } +} + +void ff_h264_idct_add_c(uint8_t *dst, DCTELEM *block, int stride){ + idct_internal(dst, block, stride, 4, 6, 1); +} + +void ff_h264_lowres_idct_add_c(uint8_t *dst, int stride, DCTELEM *block){ + idct_internal(dst, block, stride, 8, 3, 1); +} + +void ff_h264_lowres_idct_put_c(uint8_t *dst, int stride, DCTELEM *block){ + idct_internal(dst, block, stride, 8, 3, 0); +} + +void ff_h264_idct8_add_c(uint8_t *dst, DCTELEM *block, int stride){ + int i; + DCTELEM (*src)[8] = (DCTELEM(*)[8])block; + uint8_t *cm = ff_cropTbl + MAX_NEG_CROP; + + block[0] += 32; + + for( i = 0; i < 8; i++ ) + { + const int a0 = src[i][0] + src[i][4]; + const int a2 = src[i][0] - src[i][4]; + const int a4 = (src[i][2]>>1) - src[i][6]; + const int a6 = (src[i][6]>>1) + src[i][2]; + + const int b0 = a0 + a6; + const int b2 = a2 + a4; + const int b4 = a2 - a4; + const int b6 = a0 - a6; + + const int a1 = -src[i][3] + src[i][5] - src[i][7] - (src[i][7]>>1); + const int a3 = src[i][1] + src[i][7] - src[i][3] - (src[i][3]>>1); + const int a5 = -src[i][1] + src[i][7] + src[i][5] + (src[i][5]>>1); + const int a7 = src[i][3] + src[i][5] + src[i][1] + (src[i][1]>>1); + + const int b1 = (a7>>2) + a1; + const int b3 = a3 + (a5>>2); + const int b5 = (a3>>2) - a5; + const int b7 = a7 - (a1>>2); + + src[i][0] = b0 + b7; + src[i][7] = b0 - b7; + src[i][1] = b2 + b5; + src[i][6] = b2 - b5; + src[i][2] = b4 + b3; + src[i][5] = b4 - b3; + src[i][3] = b6 + b1; + src[i][4] = b6 - b1; + } + for( i = 0; i < 8; i++ ) + { + const int a0 = src[0][i] + src[4][i]; + const int a2 = src[0][i] - src[4][i]; + const int a4 = (src[2][i]>>1) - src[6][i]; + const int a6 = (src[6][i]>>1) + src[2][i]; + + const int b0 = a0 + a6; + const int b2 = a2 + a4; + const int b4 = a2 - a4; + const int b6 = a0 - a6; + + const int a1 = -src[3][i] + src[5][i] - src[7][i] - (src[7][i]>>1); + const int a3 = src[1][i] + src[7][i] - src[3][i] - (src[3][i]>>1); + const int a5 = -src[1][i] + src[7][i] + src[5][i] + (src[5][i]>>1); + const int a7 = src[3][i] + src[5][i] + src[1][i] + (src[1][i]>>1); + + const int b1 = (a7>>2) + a1; + const int b3 = a3 + (a5>>2); + const int b5 = (a3>>2) - a5; + const int b7 = a7 - (a1>>2); + + dst[i + 0*stride] = cm[ dst[i + 0*stride] + ((b0 + b7) >> 6) ]; + dst[i + 1*stride] = cm[ dst[i + 1*stride] + ((b2 + b5) >> 6) ]; + dst[i + 2*stride] = cm[ dst[i + 2*stride] + ((b4 + b3) >> 6) ]; + dst[i + 3*stride] = cm[ dst[i + 3*stride] + ((b6 + b1) >> 6) ]; + dst[i + 4*stride] = cm[ dst[i + 4*stride] + ((b6 - b1) >> 6) ]; + dst[i + 5*stride] = cm[ dst[i + 5*stride] + ((b4 - b3) >> 6) ]; + dst[i + 6*stride] = cm[ dst[i + 6*stride] + ((b2 - b5) >> 6) ]; + dst[i + 7*stride] = cm[ dst[i + 7*stride] + ((b0 - b7) >> 6) ]; + } +} + +// assumes all AC coefs are 0 +void ff_h264_idct_dc_add_c(uint8_t *dst, DCTELEM *block, int stride){ + int i, j; + uint8_t *cm = ff_cropTbl + MAX_NEG_CROP; + int dc = (block[0] + 32) >> 6; + for( j = 0; j < 4; j++ ) + { + for( i = 0; i < 4; i++ ) + dst[i] = cm[ dst[i] + dc ]; + dst += stride; + } +} + +void ff_h264_idct8_dc_add_c(uint8_t *dst, DCTELEM *block, int stride){ + int i, j; + uint8_t *cm = ff_cropTbl + MAX_NEG_CROP; + int dc = (block[0] + 32) >> 6; + for( j = 0; j < 8; j++ ) + { + for( i = 0; i < 8; i++ ) + dst[i] = cm[ dst[i] + dc ]; + dst += stride; + } +} |