| 1 | /* |
| 2 | * boxblur.c |
| 3 | * |
| 4 | * Copyright (C) Georg Martius - July 2010 |
| 5 | * georg dot martius at web dot de |
| 6 | * |
| 7 | * This file is part of vid.stab video stabilization library |
| 8 | * |
| 9 | * vid.stab is free software; you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License, |
| 11 | * as published by the Free Software Foundation; either version 2, or |
| 12 | * (at your option) any later version. |
| 13 | * |
| 14 | * vid.stab is distributed in the hope that it will be useful, |
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 | * GNU General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU General Public License |
| 20 | * along with GNU Make; see the file COPYING. If not, write to |
| 21 | * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. |
| 22 | * |
| 23 | */ |
| 24 | |
| 25 | #include "boxblur.h" |
| 26 | #include "vidstabdefines.h" |
| 27 | |
| 28 | |
| 29 | void boxblur_hori_C(unsigned char* dest, const unsigned char* src, |
| 30 | int width, int height, int dest_strive, int src_strive, int size); |
| 31 | void boxblur_vert_C(unsigned char* dest, const unsigned char* src, |
| 32 | int width, int height, int dest_strive, int src_strive, int size); |
| 33 | |
| 34 | /* |
| 35 | The algorithm: |
| 36 | box filter: kernel has only 1's |
| 37 | a good blur is obtained for multiple runs of boxblur |
| 38 | - 2 runs: tent kernel, infinity -> gaussian |
| 39 | but for our purposes is the tent kernel enough. |
| 40 | |
| 41 | horizontal and vertical 1D boxfilters can be used |
| 42 | |
| 43 | accumulator: acc = acc + new - old, pixel = acc/size |
| 44 | */ |
| 45 | |
| 46 | void boxblurPlanar(VSFrame* dest, const VSFrame* src, |
| 47 | VSFrame* buffer, const VSFrameInfo* fi, |
| 48 | unsigned int size, BoxBlurColorMode colormode){ |
| 49 | int localbuffer=0; |
| 50 | int size2; |
| 51 | if(size<2){ |
| 52 | if(dest!=src) |
| 53 | vsFrameCopy(dest,src,fi); |
| 54 | return; |
| 55 | } |
| 56 | VSFrame buf; |
| 57 | if(buffer==0){ |
| 58 | vsFrameAllocate(&buf,fi); |
| 59 | localbuffer=1; |
| 60 | }else{ |
| 61 | buf = *buffer; |
| 62 | } |
| 63 | // odd and larger than 2 and maximally half of smaller image dimension |
| 64 | size = VS_CLAMP((size/2)*2+1,3,VS_MIN(fi->height/2,fi->width/2)); |
| 65 | //printf("%i\n",size); |
| 66 | |
| 67 | // luminance |
| 68 | boxblur_hori_C(buf.data[0], src->data[0], |
| 69 | fi->width, fi->height, buf.linesize[0],src->linesize[0], size); |
| 70 | boxblur_vert_C(dest->data[0], buf.data[0], |
| 71 | fi->width, fi->height, dest->linesize[0], buf.linesize[0], size); |
| 72 | |
| 73 | size2 = size/2+1; // odd and larger than 0 |
| 74 | int plane; |
| 75 | switch (colormode){ |
| 76 | case BoxBlurColor: |
| 77 | // color |
| 78 | if(size2>1){ |
| 79 | for(plane=1; plane<fi->planes; plane++){ |
| 80 | boxblur_hori_C(buf.data[plane], src->data[plane], |
| 81 | fi->width >> vsGetPlaneWidthSubS(fi,plane), |
| 82 | fi->height >> vsGetPlaneHeightSubS(fi,plane), |
| 83 | buf.linesize[plane], src->linesize[plane], size2); |
| 84 | boxblur_vert_C(dest->data[plane], buf.data[plane], |
| 85 | fi->width >> vsGetPlaneWidthSubS(fi,plane), |
| 86 | fi->height >> vsGetPlaneHeightSubS(fi,plane), |
| 87 | dest->linesize[plane], buf.linesize[plane], size2); |
| 88 | } |
| 89 | } |
| 90 | break; |
| 91 | case BoxBlurKeepColor: |
| 92 | // copy both color channels |
| 93 | for(plane=1; plane<fi->planes; plane++){ |
| 94 | vsFrameCopyPlane(dest, src, fi, plane); |
| 95 | } |
| 96 | case BoxBlurNoColor: // do nothing |
| 97 | default: |
| 98 | break; |
| 99 | } |
| 100 | |
| 101 | if(localbuffer) |
| 102 | vsFrameFree(&buf); |
| 103 | } |
| 104 | |
| 105 | /* /\* */ |
| 106 | /* The algorithm: */ |
| 107 | /* see boxblurPlanar but here we for Packed */ |
| 108 | |
| 109 | /* we add the 3 bytes of one pixel as if they where one number */ |
| 110 | /* *\/ */ |
| 111 | /* void boxblurPacked(const unsigned char* src, unsigned char* dest, */ |
| 112 | /* unsigned char* buffer, const VSFrameInfo* fi, */ |
| 113 | /* unsigned int size){ */ |
| 114 | /* int localbuffer=0; */ |
| 115 | /* if(buffer==0){ */ |
| 116 | /* buffer=(unsigned char*) vs_malloc(fi->framesize); */ |
| 117 | /* localbuffer=1; */ |
| 118 | /* } */ |
| 119 | /* // odd and larger than 2 and maximal half of smaller image dimension */ |
| 120 | /* // (and not larger than 256, because otherwise we can get an overflow) */ |
| 121 | /* size = VS_CLAMP((size/2)*2+1,3,VS_MIN(256,VS_MIN(fi->height/2,fi->width/2))); */ |
| 122 | |
| 123 | /* // we need a different version of these functions for Packed */ |
| 124 | /* boxblur_hori_C(src, buffer, fi->width, fi->height, fi->strive, size); */ |
| 125 | /* boxblur_vert_C(buffer, dest, fi->width, fi->height, fi->strive, size); */ |
| 126 | |
| 127 | /* if(localbuffer) */ |
| 128 | /* vs_free(buffer); */ |
| 129 | /* } */ |
| 130 | |
| 131 | |
| 132 | void boxblur_hori_C(unsigned char* dest, const unsigned char* src, |
| 133 | int width, int height, int dest_strive, int src_strive, int size){ |
| 134 | |
| 135 | int i,j,k; |
| 136 | unsigned int acc; |
| 137 | const unsigned char *start, *end; // start and end of kernel |
| 138 | unsigned char *current; // current destination pixel |
| 139 | int size2 = size/2; // size of one side of the kernel without center |
| 140 | // #pragma omp parallel for private(acc),schedule(guided,2) (no speedup) |
| 141 | for(j=0; j< height; j++){ |
| 142 | // for(j=100; j< 101; j++){ |
| 143 | start = end = src + j*src_strive; |
| 144 | current = dest + j*dest_strive; |
| 145 | // initialize accumulator |
| 146 | acc= (*start)*(size2+1); // left half of kernel with first pixel |
| 147 | for(k=0; k<size2; k++){ // right half of kernel |
| 148 | acc+=(*end); |
| 149 | end++; |
| 150 | } |
| 151 | // go through the image |
| 152 | for(i=0; i< width; i++){ |
| 153 | acc = acc + (*end) - (*start); |
| 154 | if(i > size2) start++; |
| 155 | if(i < width - size2 - 1) end++; |
| 156 | (*current) = acc/size; |
| 157 | current++; |
| 158 | } |
| 159 | } |
| 160 | } |
| 161 | |
| 162 | void boxblur_vert_C(unsigned char* dest, const unsigned char* src, |
| 163 | int width, int height, int dest_strive, int src_strive, int size){ |
| 164 | |
| 165 | int i,j,k; |
| 166 | int acc; |
| 167 | const unsigned char *start, *end; // start and end of kernel |
| 168 | unsigned char *current; // current destination pixel |
| 169 | int size2 = size/2; // size of one side of the kernel without center |
| 170 | for(i=0; i< width; i++){ |
| 171 | start = end = src + i; |
| 172 | current = dest + i; |
| 173 | // initialize accumulator |
| 174 | acc= (*start)*(size2+1); // left half of kernel with first pixel |
| 175 | for(k=0; k<size2; k++){ // right half of kernel |
| 176 | acc+=(*end); |
| 177 | end+=src_strive; |
| 178 | } |
| 179 | // go through the image |
| 180 | for(j=0; j< height; j++){ |
| 181 | acc = acc - (*start) + (*end); |
| 182 | if(j > size2) start+=src_strive; |
| 183 | if(j < height - size2 - 1) end+=src_strive; |
| 184 | *current = acc/size; |
| 185 | current+=dest_strive; |
| 186 | } |
| 187 | } |
| 188 | } |