lib/src/jp/nyatla/nyartoolkit/core/rasterfilter/NyARRasterFilter_Roberts.java

   1 /* \r
   2  * PROJECT: NyARToolkit(Extension)\r
   3  * --------------------------------------------------------------------------------\r
   4  * The NyARToolkit is Java edition ARToolKit class library.\r
   5  * Copyright (C)2008-2009 Ryo Iizuka\r
   6  *\r
   7  * This program is free software: you can redistribute it and/or modify\r
   8  * it under the terms of the GNU General Public License as published by\r
   9  * the Free Software Foundation, either version 3 of the License, or\r
  10  * (at your option) any later version.\r
  11  * \r
  12  * This program is distributed in the hope that it will be useful,\r
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of\r
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\r
  15  * GNU General Public License for more details.\r
  16  *\r
  17  * You should have received a copy of the GNU General Public License\r
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.\r
  19  * \r
  20  * For further information please contact.\r
  21  *      http://nyatla.jp/nyatoolkit/\r
  22  *      <airmail(at)ebony.plala.or.jp> or <nyatla(at)nyatla.jp>\r
  23  * \r
  24  */\r
  25 package jp.nyatla.nyartoolkit.core.rasterfilter;\r
  26 \r
  27 import jp.nyatla.nyartoolkit.NyARException;\r
  28 import jp.nyatla.nyartoolkit.core.raster.*;\r
  29 import jp.nyatla.nyartoolkit.core.types.NyARBufferType;\r
  30 import jp.nyatla.nyartoolkit.core.types.NyARIntSize;\r
  31 \r
  32 /**\r
  33  * Roberts法で勾配を計算します。\r
  34  * 右端と左端の1ピクセルは、常に0が入ります。\r
  35  * X=|-1, 0|  Y=|0,-1|\r
  36  *   | 0, 1|    |1, 0|\r
  37  * V=sqrt(X^2+Y+2)/2\r
  38  */\r
  39 public class NyARRasterFilter_Roberts implements INyARRasterFilter\r
  40 {\r
  41         private IdoFilterImpl _do_filter_impl; \r
  42         public NyARRasterFilter_Roberts(int i_raster_type) throws NyARException\r
  43         {\r
  44                 switch (i_raster_type) {\r
  45                 case NyARBufferType.INT1D_GRAY_8:\r
  46                         this._do_filter_impl=new IdoFilterImpl_GRAY_8();\r
  47                         break;\r
  48                 default:\r
  49                         throw new NyARException();\r
  50                 }\r
  51         }\r
  52         public void doFilter(INyARRaster i_input, INyARRaster i_output) throws NyARException\r
  53         {\r
  54                 this._do_filter_impl.doFilter(i_input,i_output,i_input.getSize());\r
  55         }\r
  56         \r
  57         interface IdoFilterImpl\r
  58         {\r
  59                 public void doFilter(INyARRaster i_input, INyARRaster i_output,NyARIntSize i_size) throws NyARException;\r
  60         }\r
  61         class IdoFilterImpl_GRAY_8 implements IdoFilterImpl\r
  62         {\r
  63                 public void doFilter(INyARRaster i_input, INyARRaster i_output,NyARIntSize i_size) throws NyARException\r
  64                 {\r
  65                         assert (i_input.isEqualBufferType(NyARBufferType.INT1D_GRAY_8));\r
  66                         assert (i_output.isEqualBufferType(NyARBufferType.INT1D_GRAY_8));\r
  67                         int[] in_ptr =(int[])i_input.getBuffer();\r
  68                         int[] out_ptr=(int[])i_output.getBuffer();\r
  69                         int width=i_size.w;\r
  70                         int idx=0;\r
  71                         int idx2=width;\r
  72                         int fx,fy;\r
  73                         int mod_p=(width-2)-(width-2)%8;\r
  74                         for(int y=i_size.h-2;y>=0;y--){\r
  75                                 int p00=in_ptr[idx++];\r
  76                                 int p10=in_ptr[idx2++];\r
  77                                 int p01,p11;\r
  78                                 int x=width-2;\r
  79                                 for(;x>=mod_p;x--){\r
  80                                         p01=in_ptr[idx++];p11=in_ptr[idx2++];\r
  81                                         fx=p11-p00;fy=p10-p01;\r
  82                                         out_ptr[idx-2]=((fx<0?-fx:fx)+(fy<0?-fy:fy))>>1;\r
  83                                         p00=p01;\r
  84                                         p10=p11;\r
  85                                 }\r
  86                                 for(;x>=0;x-=4){\r
  87                                         p01=in_ptr[idx++];p11=in_ptr[idx2++];\r
  88                                         fx=p11-p00;\r
  89                                         fy=p10-p01;\r
  90                                         out_ptr[idx-2]=((fx<0?-fx:fx)+(fy<0?-fy:fy))>>1;\r
  91                                         p00=p01;p10=p11;\r
  92 \r
  93                                         p01=in_ptr[idx++];p11=in_ptr[idx2++];\r
  94                                         fx=p11-p00;\r
  95                                         fy=p10-p01;\r
  96                                         out_ptr[idx-2]=((fx<0?-fx:fx)+(fy<0?-fy:fy))>>1;\r
  97                                         p00=p01;p10=p11;\r
  98                                         p01=in_ptr[idx++];p11=in_ptr[idx2++];\r
  99                                         \r
 100                                         fx=p11-p00;\r
 101                                         fy=p10-p01;\r
 102                                         out_ptr[idx-2]=((fx<0?-fx:fx)+(fy<0?-fy:fy))>>1;\r
 103                                         p00=p01;p10=p11;\r
 104 \r
 105                                         p01=in_ptr[idx++];p11=in_ptr[idx2++];\r
 106                                         fx=p11-p00;\r
 107                                         fy=p10-p01;\r
 108                                         out_ptr[idx-2]=((fx<0?-fx:fx)+(fy<0?-fy:fy))>>1;\r
 109                                         p00=p01;p10=p11;\r
 110 \r
 111                                 }\r
 112                                 out_ptr[idx-1]=0;\r
 113                         }\r
 114                         for(int x=width-1;x>=0;x--){\r
 115                                 out_ptr[idx++]=0;\r
 116                         }\r
 117                         return;\r
 118                 }\r
 119         }\r
 120 }\r
 121 \r