diff options
Diffstat (limited to 'libavcodec/h263dsp.c')
| -rw-r--r-- | libavcodec/h263dsp.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/libavcodec/h263dsp.c b/libavcodec/h263dsp.c new file mode 100644 index 0000000000..a6a9347b59 --- /dev/null +++ b/libavcodec/h263dsp.c @@ -0,0 +1,108 @@ +/* + * 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 + */ + +#include <stdint.h> + +#include "libavutil/attributes.h" +#include "libavutil/common.h" +#include "config.h" +#include "h263dsp.h" + +const uint8_t ff_h263_loop_filter_strength[32]={ +// 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 + 0, 1, 1, 2, 2, 3, 3, 4, 4, 4, 5, 5, 6, 6, 7, 7, 7, 8, 8, 8, 9, 9, 9,10,10,10,11,11,11,12,12,12 +}; + +static void h263_h_loop_filter_c(uint8_t *src, int stride, int qscale){ + int y; + const int strength= ff_h263_loop_filter_strength[qscale]; + + for(y=0; y<8; y++){ + int d1, d2, ad1; + int p0= src[y*stride-2]; + int p1= src[y*stride-1]; + int p2= src[y*stride+0]; + int p3= src[y*stride+1]; + int d = (p0 - p3 + 4*(p2 - p1)) / 8; + + if (d<-2*strength) d1= 0; + else if(d<- strength) d1=-2*strength - d; + else if(d< strength) d1= d; + else if(d< 2*strength) d1= 2*strength - d; + else d1= 0; + + p1 += d1; + p2 -= d1; + if(p1&256) p1= ~(p1>>31); + if(p2&256) p2= ~(p2>>31); + + src[y*stride-1] = p1; + src[y*stride+0] = p2; + + ad1= FFABS(d1)>>1; + + d2= av_clip((p0-p3)/4, -ad1, ad1); + + src[y*stride-2] = p0 - d2; + src[y*stride+1] = p3 + d2; + } +} + +static void h263_v_loop_filter_c(uint8_t *src, int stride, int qscale){ + int x; + const int strength= ff_h263_loop_filter_strength[qscale]; + + for(x=0; x<8; x++){ + int d1, d2, ad1; + int p0= src[x-2*stride]; + int p1= src[x-1*stride]; + int p2= src[x+0*stride]; + int p3= src[x+1*stride]; + int d = (p0 - p3 + 4*(p2 - p1)) / 8; + + if (d<-2*strength) d1= 0; + else if(d<- strength) d1=-2*strength - d; + else if(d< strength) d1= d; + else if(d< 2*strength) d1= 2*strength - d; + else d1= 0; + + p1 += d1; + p2 -= d1; + if(p1&256) p1= ~(p1>>31); + if(p2&256) p2= ~(p2>>31); + + src[x-1*stride] = p1; + src[x+0*stride] = p2; + + ad1= FFABS(d1)>>1; + + d2= av_clip((p0-p3)/4, -ad1, ad1); + + src[x-2*stride] = p0 - d2; + src[x+ stride] = p3 + d2; + } +} + +av_cold void ff_h263dsp_init(H263DSPContext *ctx) +{ + ctx->h263_h_loop_filter = h263_h_loop_filter_c; + ctx->h263_v_loop_filter = h263_v_loop_filter_c; + + if (ARCH_X86) + ff_h263dsp_init_x86(ctx); +} |