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<hr><h1>overview.cpp</h1><div class="fragment"><pre>00001 <font class="comment">/******************************************************************************</font>
00002 <font class="comment"> * $Id: overview_cpp-source.html,v 1.10 2002/04/16 13:11:49 warmerda Exp $</font>
00003 <font class="comment"> *</font>
00004 <font class="comment"> * Project: GDAL Core</font>
00005 <font class="comment"> * Purpose: Helper code to implement overview support in different drivers.</font>
00006 <font class="comment"> * Author: Frank Warmerdam, warmerda@home.com</font>
00007 <font class="comment"> *</font>
00008 <font class="comment"> ******************************************************************************</font>
00009 <font class="comment"> * Copyright (c) 2000, Frank Warmerdam</font>
00010 <font class="comment"> *</font>
00011 <font class="comment"> * Permission is hereby granted, free of charge, to any person obtaining a</font>
00012 <font class="comment"> * copy of this software and associated documentation files (the "Software"),</font>
00013 <font class="comment"> * to deal in the Software without restriction, including without limitation</font>
00014 <font class="comment"> * the rights to use, copy, modify, merge, publish, distribute, sublicense,</font>
00015 <font class="comment"> * and/or sell copies of the Software, and to permit persons to whom the</font>
00016 <font class="comment"> * Software is furnished to do so, subject to the following conditions:</font>
00017 <font class="comment"> *</font>
00018 <font class="comment"> * The above copyright notice and this permission notice shall be included</font>
00019 <font class="comment"> * in all copies or substantial portions of the Software.</font>
00020 <font class="comment"> *</font>
00021 <font class="comment"> * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS</font>
00022 <font class="comment"> * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,</font>
00023 <font class="comment"> * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL</font>
00024 <font class="comment"> * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER</font>
00025 <font class="comment"> * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING</font>
00026 <font class="comment"> * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER</font>
00027 <font class="comment"> * DEALINGS IN THE SOFTWARE.</font>
00028 <font class="comment"> ******************************************************************************</font>
00029 <font class="comment"> *</font>
00030 <font class="comment"> * $Log: overview_cpp-source.html,v $
00030 <font class="comment"> * Revision 1.10 2002/04/16 13:11:49 warmerda
00030 <font class="comment"> * updated
00030 <font class="comment"> *</font>
00031 <font class="comment"> * Revision 1.8 2001/07/18 04:04:30 warmerda</font>
00032 <font class="comment"> * added CPL_CVSID</font>
00033 <font class="comment"> *</font>
00034 <font class="comment"> * Revision 1.7 2001/07/16 15:21:46 warmerda</font>
00035 <font class="comment"> * added AVERAGE_MAGPHASE option for complex images</font>
00036 <font class="comment"> *</font>
00037 <font class="comment"> * Revision 1.6 2001/01/30 22:32:42 warmerda</font>
00038 <font class="comment"> * added AVERAGE_MP (magnitude preserving averaging) overview resampling type</font>
00039 <font class="comment"> *</font>
00040 <font class="comment"> * Revision 1.5 2000/11/22 18:41:45 warmerda</font>
00041 <font class="comment"> * fixed bug in complex overview generation</font>
00042 <font class="comment"> *</font>
00043 <font class="comment"> * Revision 1.4 2000/08/18 15:25:06 warmerda</font>
00044 <font class="comment"> * added cascading overview regeneration to speed up averaged overviews</font>
00045 <font class="comment"> *</font>
00046 <font class="comment"> * Revision 1.3 2000/07/17 17:08:45 warmerda</font>
00047 <font class="comment"> * added support for complex data</font>
00048 <font class="comment"> *</font>
00049 <font class="comment"> * Revision 1.2 2000/06/26 22:17:58 warmerda</font>
00050 <font class="comment"> * added scaled progress support</font>
00051 <font class="comment"> *</font>
00052 <font class="comment"> * Revision 1.1 2000/04/21 21:54:05 warmerda</font>
00053 <font class="comment"> * New</font>
00054 <font class="comment"> *</font>
00055 <font class="comment"> */</font>
00056
00057 <font class="preprocessor">#include "gdal_priv.h"</font>
00058
00059 CPL_CVSID(<font class="stringliteral">"$Id: overview_cpp-source.html,v 1.10 2002/04/16 13:11:49 warmerda Exp $"</font>);
00060
00061 <font class="comment">/************************************************************************/</font>
00062 <font class="comment">/* GDALDownsampleChunk32R() */</font>
00063 <font class="comment">/************************************************************************/</font>
00064
00065 <font class="keyword">static</font> CPLErr
00066 GDALDownsampleChunk32R( <font class="keywordtype">int</font> nSrcWidth, <font class="keywordtype">int</font> nSrcHeight,
00067 <font class="keywordtype">float</font> * pafChunk, <font class="keywordtype">int</font> nChunkYOff, <font class="keywordtype">int</font> nChunkYSize,
00068 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> * poOverview,
00069 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszResampling )<font class="keyword"></font>
00070 <font class="keyword"></font>
00071 <font class="keyword"></font>{
00072 <font class="keywordtype">int</font> nDstYOff, nDstYOff2, nOXSize, nOYSize;
00073 <font class="keywordtype">float</font> *pafDstScanline;
00074
00075 nOXSize = poOverview-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>();
00076 nOYSize = poOverview-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00077
00078 pafDstScanline = (<font class="keywordtype">float</font> *) <a class="code" href="cpl_conv_h.html#a3">CPLMalloc</a>(nOXSize * <font class="keyword">sizeof</font>(<font class="keywordtype">float</font>));
00079
00080 <font class="comment">/* -------------------------------------------------------------------- */</font>
00081 <font class="comment">/* Figure out the line to start writing to, and the first line */</font>
00082 <font class="comment">/* to not write to. In theory this approach should ensure that */</font>
00083 <font class="comment">/* every output line will be written if all input chunks are */</font>
00084 <font class="comment">/* processed. */</font>
00085 <font class="comment">/* -------------------------------------------------------------------- */</font>
00086 nDstYOff = (<font class="keywordtype">int</font>) (0.5 + (nChunkYOff/(<font class="keywordtype">double</font>)nSrcHeight) * nOYSize);
00087 nDstYOff2 = (<font class="keywordtype">int</font>)
00088 (0.5 + ((nChunkYOff+nChunkYSize)/(<font class="keywordtype">double</font>)nSrcHeight) * nOYSize);
00089
00090 <font class="keywordflow">if</font>( nChunkYOff + nChunkYSize == nSrcHeight )
00091 nDstYOff2 = nOYSize;
00092
00093 <font class="comment">/* ==================================================================== */</font>
00094 <font class="comment">/* Loop over destination scanlines. */</font>
00095 <font class="comment">/* ==================================================================== */</font>
00096 <font class="keywordflow">for</font>( <font class="keywordtype">int</font> iDstLine = nDstYOff; iDstLine < nDstYOff2; iDstLine++ )
00097 {
00098 <font class="keywordtype">float</font> *pafSrcScanline;
00099 <font class="keywordtype">int</font> nSrcYOff, nSrcYOff2, iDstPixel;
00100
00101 nSrcYOff = (<font class="keywordtype">int</font>) (0.5 + (iDstLine/(<font class="keywordtype">double</font>)nOYSize) * nSrcHeight);
00102 <font class="keywordflow">if</font>( nSrcYOff < nChunkYOff )
00103 nSrcYOff = nChunkYOff;
00104
00105 nSrcYOff2 = (<font class="keywordtype">int</font>) (0.5 + ((iDstLine+1)/(<font class="keywordtype">double</font>)nOYSize) * nSrcHeight);
00106 <font class="keywordflow">if</font>( nSrcYOff2 > nSrcHeight || iDstLine == nOYSize-1 )
00107 nSrcYOff2 = nSrcHeight;
00108 <font class="keywordflow">if</font>( nSrcYOff2 > nChunkYOff + nChunkYSize )
00109 nSrcYOff2 = nChunkYOff + nChunkYSize;
00110
00111 pafSrcScanline = pafChunk + ((nSrcYOff-nChunkYOff) * nSrcWidth);
00112
00113 <font class="comment">/* -------------------------------------------------------------------- */</font>
00114 <font class="comment">/* Loop over destination pixels */</font>
00115 <font class="comment">/* -------------------------------------------------------------------- */</font>
00116 <font class="keywordflow">for</font>( iDstPixel = 0; iDstPixel < nOXSize; iDstPixel++ )
00117 {
00118 <font class="keywordtype">int</font> nSrcXOff, nSrcXOff2;
00119
00120 nSrcXOff = (<font class="keywordtype">int</font>) (0.5 + (iDstPixel/(<font class="keywordtype">double</font>)nOXSize) * nSrcWidth);
00121 nSrcXOff2 = (<font class="keywordtype">int</font>)
00122 (0.5 + ((iDstPixel+1)/(<font class="keywordtype">double</font>)nOXSize) * nSrcWidth);
00123 <font class="keywordflow">if</font>( nSrcXOff2 > nSrcWidth )
00124 nSrcXOff2 = nSrcWidth;
00125
00126 <font class="keywordflow">if</font>( EQUALN(pszResampling,<font class="stringliteral">"NEAR"</font>,4) )
00127 {
00128 pafDstScanline[iDstPixel] = pafSrcScanline[nSrcXOff];
00129 }
00130 <font class="keywordflow">else</font> <font class="keywordflow">if</font>( EQUALN(pszResampling,<font class="stringliteral">"AVER"</font>,4) )
00131 {
00132 <font class="keywordtype">double</font> dfTotal = 0.0;
00133 <font class="keywordtype">int</font> nCount = 0, iX, iY;
00134
00135 <font class="keywordflow">for</font>( iY = nSrcYOff; iY < nSrcYOff2; iY++ )
00136 {
00137 <font class="keywordflow">for</font>( iX = nSrcXOff; iX < nSrcXOff2; iX++ )
00138 {
00139 dfTotal += pafSrcScanline[iX+(iY-nSrcYOff)*nSrcWidth];
00140 nCount++;
00141 }
00142 }
00143
00144 CPLAssert( nCount > 0 );
00145 <font class="keywordflow">if</font>( nCount == 0 )
00146 {
00147 pafDstScanline[iDstPixel] = 0.0;
00148 }
00149 <font class="keywordflow">else</font>
00150 pafDstScanline[iDstPixel] = dfTotal / nCount;
00151 }
00152 }
00153
00154 poOverview-><a class="code" href="class_GDALRasterBand.html#a8">RasterIO</a>( GF_Write, 0, iDstLine, nOXSize, 1,
00155 pafDstScanline, nOXSize, 1, GDT_Float32,
00156 0, 0 );
00157 }
00158
00159 CPLFree( pafDstScanline );
00160
00161 <font class="keywordflow">return</font> CE_None;
00162 }
00163
00164 <font class="comment">/************************************************************************/</font>
00165 <font class="comment">/* GDALDownsampleChunkC32R() */</font>
00166 <font class="comment">/************************************************************************/</font>
00167
00168 <font class="keyword">static</font> CPLErr
00169 GDALDownsampleChunkC32R( <font class="keywordtype">int</font> nSrcWidth, <font class="keywordtype">int</font> nSrcHeight,
00170 <font class="keywordtype">float</font> * pafChunk, <font class="keywordtype">int</font> nChunkYOff, <font class="keywordtype">int</font> nChunkYSize,
00171 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> * poOverview,
00172 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszResampling )<font class="keyword"></font>
00173 <font class="keyword"> </font>
00174 <font class="keyword"></font>{
00175 <font class="keywordtype">int</font> nDstYOff, nDstYOff2, nOXSize, nOYSize;
00176 <font class="keywordtype">float</font> *pafDstScanline;
00177
00178 nOXSize = poOverview-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>();
00179 nOYSize = poOverview-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00180
00181 pafDstScanline = (<font class="keywordtype">float</font> *) <a class="code" href="cpl_conv_h.html#a3">CPLMalloc</a>(nOXSize * <font class="keyword">sizeof</font>(<font class="keywordtype">float</font>) * 2);
00182
00183 <font class="comment">/* -------------------------------------------------------------------- */</font>
00184 <font class="comment">/* Figure out the line to start writing to, and the first line */</font>
00185 <font class="comment">/* to not write to. In theory this approach should ensure that */</font>
00186 <font class="comment">/* every output line will be written if all input chunks are */</font>
00187 <font class="comment">/* processed. */</font>
00188 <font class="comment">/* -------------------------------------------------------------------- */</font>
00189 nDstYOff = (<font class="keywordtype">int</font>) (0.5 + (nChunkYOff/(<font class="keywordtype">double</font>)nSrcHeight) * nOYSize);
00190 nDstYOff2 = (<font class="keywordtype">int</font>)
00191 (0.5 + ((nChunkYOff+nChunkYSize)/(<font class="keywordtype">double</font>)nSrcHeight) * nOYSize);
00192
00193 <font class="keywordflow">if</font>( nChunkYOff + nChunkYSize == nSrcHeight )
00194 nDstYOff2 = nOYSize;
00195
00196 <font class="comment">/* ==================================================================== */</font>
00197 <font class="comment">/* Loop over destination scanlines. */</font>
00198 <font class="comment">/* ==================================================================== */</font>
00199 <font class="keywordflow">for</font>( <font class="keywordtype">int</font> iDstLine = nDstYOff; iDstLine < nDstYOff2; iDstLine++ )
00200 {
00201 <font class="keywordtype">float</font> *pafSrcScanline;
00202 <font class="keywordtype">int</font> nSrcYOff, nSrcYOff2, iDstPixel;
00203
00204 nSrcYOff = (<font class="keywordtype">int</font>) (0.5 + (iDstLine/(<font class="keywordtype">double</font>)nOYSize) * nSrcHeight);
00205 <font class="keywordflow">if</font>( nSrcYOff < nChunkYOff )
00206 nSrcYOff = nChunkYOff;
00207
00208 nSrcYOff2 = (<font class="keywordtype">int</font>) (0.5 + ((iDstLine+1)/(<font class="keywordtype">double</font>)nOYSize) * nSrcHeight);
00209 <font class="keywordflow">if</font>( nSrcYOff2 > nSrcHeight || iDstLine == nOYSize-1 )
00210 nSrcYOff2 = nSrcHeight;
00211 <font class="keywordflow">if</font>( nSrcYOff2 > nChunkYOff + nChunkYSize )
00212 nSrcYOff2 = nChunkYOff + nChunkYSize;
00213
00214 pafSrcScanline = pafChunk + ((nSrcYOff-nChunkYOff) * nSrcWidth) * 2;
00215
00216 <font class="comment">/* -------------------------------------------------------------------- */</font>
00217 <font class="comment">/* Loop over destination pixels */</font>
00218 <font class="comment">/* -------------------------------------------------------------------- */</font>
00219 <font class="keywordflow">for</font>( iDstPixel = 0; iDstPixel < nOXSize; iDstPixel++ )
00220 {
00221 <font class="keywordtype">int</font> nSrcXOff, nSrcXOff2;
00222
00223 nSrcXOff = (<font class="keywordtype">int</font>) (0.5 + (iDstPixel/(<font class="keywordtype">double</font>)nOXSize) * nSrcWidth);
00224 nSrcXOff2 = (<font class="keywordtype">int</font>)
00225 (0.5 + ((iDstPixel+1)/(<font class="keywordtype">double</font>)nOXSize) * nSrcWidth);
00226 <font class="keywordflow">if</font>( nSrcXOff2 > nSrcWidth )
00227 nSrcXOff2 = nSrcWidth;
00228
00229 <font class="keywordflow">if</font>( EQUALN(pszResampling,<font class="stringliteral">"NEAR"</font>,4) )
00230 {
00231 pafDstScanline[iDstPixel*2] = pafSrcScanline[nSrcXOff*2];
00232 pafDstScanline[iDstPixel*2+1] = pafSrcScanline[nSrcXOff*2+1];
00233 }
00234 <font class="keywordflow">else</font> <font class="keywordflow">if</font>( EQUAL(pszResampling,<font class="stringliteral">"AVERAGE_MAGPHASE"</font>) )
00235 {
00236 <font class="keywordtype">double</font> dfTotalR = 0.0, dfTotalI = 0.0, dfTotalM = 0.0;
00237 <font class="keywordtype">int</font> nCount = 0, iX, iY;
00238
00239 <font class="keywordflow">for</font>( iY = nSrcYOff; iY < nSrcYOff2; iY++ )
00240 {
00241 <font class="keywordflow">for</font>( iX = nSrcXOff; iX < nSrcXOff2; iX++ )
00242 {
00243 <font class="keywordtype">double</font> dfR, dfI;
00244
00245 dfR = pafSrcScanline[iX*2+(iY-nSrcYOff)*nSrcWidth*2];
00246 dfI = pafSrcScanline[iX*2+(iY-nSrcYOff)*nSrcWidth*2+1];
00247 dfTotalR += dfR;
00248 dfTotalI += dfI;
00249 dfTotalM += sqrt( dfR*dfR + dfI*dfI );
00250 nCount++;
00251 }
00252 }
00253
00254 CPLAssert( nCount > 0 );
00255 <font class="keywordflow">if</font>( nCount == 0 )
00256 {
00257 pafDstScanline[iDstPixel*2] = 0.0;
00258 pafDstScanline[iDstPixel*2+1] = 0.0;
00259 }
00260 <font class="keywordflow">else</font>
00261 {
00262 <font class="keywordtype">double</font> dfM, dfDesiredM, dfRatio;
00263
00264 pafDstScanline[iDstPixel*2 ] = dfTotalR / nCount;
00265 pafDstScanline[iDstPixel*2+1] = dfTotalI / nCount;
00266
00267 dfM = sqrt(pafDstScanline[iDstPixel*2 ]*pafDstScanline[iDstPixel*2 ]
00268 + pafDstScanline[iDstPixel*2+1]*pafDstScanline[iDstPixel*2+1]);
00269 dfDesiredM = dfTotalM / nCount;
00270 <font class="keywordflow">if</font>( dfM != 0.0 )
00271 dfRatio = dfDesiredM / dfM;
00272
00273 pafDstScanline[iDstPixel*2 ] *= dfRatio;
00274 pafDstScanline[iDstPixel*2+1] *= dfRatio;
00275 }
00276 }
00277 <font class="keywordflow">else</font> <font class="keywordflow">if</font>( EQUALN(pszResampling,<font class="stringliteral">"AVER"</font>,4) )
00278 {
00279 <font class="keywordtype">double</font> dfTotalR = 0.0, dfTotalI = 0.0;
00280 <font class="keywordtype">int</font> nCount = 0, iX, iY;
00281
00282 <font class="keywordflow">for</font>( iY = nSrcYOff; iY < nSrcYOff2; iY++ )
00283 {
00284 <font class="keywordflow">for</font>( iX = nSrcXOff; iX < nSrcXOff2; iX++ )
00285 {
00286 dfTotalR += pafSrcScanline[iX*2+(iY-nSrcYOff)*nSrcWidth*2];
00287 dfTotalI += pafSrcScanline[iX*2+(iY-nSrcYOff)*nSrcWidth*2+1];
00288 nCount++;
00289 }
00290 }
00291
00292 CPLAssert( nCount > 0 );
00293 <font class="keywordflow">if</font>( nCount == 0 )
00294 {
00295 pafDstScanline[iDstPixel*2] = 0.0;
00296 pafDstScanline[iDstPixel*2+1] = 0.0;
00297 }
00298 <font class="keywordflow">else</font>
00299 {
00300 pafDstScanline[iDstPixel*2 ] = dfTotalR / nCount;
00301 pafDstScanline[iDstPixel*2+1] = dfTotalI / nCount;
00302 }
00303 }
00304 }
00305
00306 poOverview-><a class="code" href="class_GDALRasterBand.html#a8">RasterIO</a>( GF_Write, 0, iDstLine, nOXSize, 1,
00307 pafDstScanline, nOXSize, 1, GDT_CFloat32,
00308 0, 0 );
00309 }
00310
00311 CPLFree( pafDstScanline );
00312
00313 <font class="keywordflow">return</font> CE_None;
00314 }
00315
00316 <font class="comment">/************************************************************************/</font>
00317 <font class="comment">/* GDALRegenerateCascadingOverviews() */</font>
00318 <font class="comment">/* */</font>
00319 <font class="comment">/* Generate a list of overviews in order from largest to */</font>
00320 <font class="comment">/* smallest, computing each from the next larger. */</font>
00321 <font class="comment">/************************************************************************/</font>
00322
00323 <font class="keyword">static</font> CPLErr
00324 GDALRegenerateCascadingOverviews(
00325 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poSrcBand, <font class="keywordtype">int</font> nOverviews, <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> **papoOvrBands,
00326 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszResampling,
00327 GDALProgressFunc pfnProgress, <font class="keywordtype">void</font> * pProgressData )<font class="keyword"></font>
00328 <font class="keyword"></font>
00329 <font class="keyword"></font>{
00330 <font class="comment">/* -------------------------------------------------------------------- */</font>
00331 <font class="comment">/* First, we must put the overviews in order from largest to */</font>
00332 <font class="comment">/* smallest. */</font>
00333 <font class="comment">/* -------------------------------------------------------------------- */</font>
00334 <font class="keywordtype">int</font> i, j;
00335
00336 <font class="keywordflow">for</font>( i = 0; i < nOverviews-1; i++ )
00337 {
00338 <font class="keywordflow">for</font>( j = 0; j < nOverviews - i - 1; j++ )
00339 {
00340
00341 <font class="keywordflow">if</font>( papoOvrBands[j]-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>()
00342 * (<font class="keywordtype">float</font>) papoOvrBands[j]-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>() <
00343 papoOvrBands[j+1]-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>()
00344 * (<font class="keywordtype">float</font>) papoOvrBands[j+1]-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>() )
00345 {
00346 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> * poTempBand;
00347
00348 poTempBand = papoOvrBands[j];
00349 papoOvrBands[j] = papoOvrBands[j+1];
00350 papoOvrBands[j+1] = poTempBand;
00351 }
00352 }
00353 }
00354
00355 <font class="comment">/* -------------------------------------------------------------------- */</font>
00356 <font class="comment">/* Count total pixels so we can prepare appropriate scaled */</font>
00357 <font class="comment">/* progress functions. */</font>
00358 <font class="comment">/* -------------------------------------------------------------------- */</font>
00359 <font class="keywordtype">double</font> dfTotalPixels = 0.0;
00360
00361 <font class="keywordflow">for</font>( i = 0; i < nOverviews; i++ )
00362 {
00363 dfTotalPixels += papoOvrBands[i]-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>()
00364 * (<font class="keywordtype">double</font>) papoOvrBands[i]-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00365 }
00366
00367 <font class="comment">/* -------------------------------------------------------------------- */</font>
00368 <font class="comment">/* Generate all the bands. */</font>
00369 <font class="comment">/* -------------------------------------------------------------------- */</font>
00370 <font class="keywordtype">double</font> dfPixelsProcessed = 0.0;
00371
00372 <font class="keywordflow">for</font>( i = 0; i < nOverviews; i++ )
00373 {
00374 <font class="keywordtype">void</font> *pScaledProgressData;
00375 <font class="keywordtype">double</font> dfPixels;
00376 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poBaseBand;
00377 CPLErr eErr;
00378
00379 <font class="keywordflow">if</font>( i == 0 )
00380 poBaseBand = poSrcBand;
00381 <font class="keywordflow">else</font>
00382 poBaseBand = papoOvrBands[i-1];
00383
00384 dfPixels = papoOvrBands[i]-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>()
00385 * (<font class="keywordtype">double</font>) papoOvrBands[i]-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00386
00387 pScaledProgressData = GDALCreateScaledProgress(
00388 dfPixelsProcessed / dfTotalPixels,
00389 (dfPixelsProcessed + dfPixels) / dfTotalPixels,
00390 pfnProgress, pProgressData );
00391
00392 eErr = GDALRegenerateOverviews( poBaseBand, 1, papoOvrBands + i,
00393 pszResampling,
00394 GDALScaledProgress,
00395 pScaledProgressData );
00396 GDALDestroyScaledProgress( pScaledProgressData );
00397
00398 <font class="keywordflow">if</font>( eErr != CE_None )
00399 <font class="keywordflow">return</font> eErr;
00400
00401 dfPixelsProcessed += dfPixels;
00402 }
00403
00404 <font class="keywordflow">return</font> CE_None;
00405 }
00406
00407 <font class="comment">/************************************************************************/</font>
00408 <font class="comment">/* GDALRegenerateOverviews() */</font>
00409 <font class="comment">/************************************************************************/</font>
00410 CPLErr
00411 GDALRegenerateOverviews( <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poSrcBand,
00412 <font class="keywordtype">int</font> nOverviews, <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> **papoOvrBands,
00413 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszResampling,
00414 GDALProgressFunc pfnProgress, <font class="keywordtype">void</font> * pProgressData )<font class="keyword"></font>
00415 <font class="keyword"></font>
00416 <font class="keyword"></font>{
00417 <font class="keywordtype">int</font> nFullResYChunk, nWidth;
00418 <font class="keywordtype">int</font> nFRXBlockSize, nFRYBlockSize;
00419 GDALDataType eType;
00420
00421 <font class="comment">/* -------------------------------------------------------------------- */</font>
00422 <font class="comment">/* If we are operating on multiple overviews, and using */</font>
00423 <font class="comment">/* averaging, lets do them in cascading order to reduce the */</font>
00424 <font class="comment">/* amount of computation. */</font>
00425 <font class="comment">/* -------------------------------------------------------------------- */</font>
00426 <font class="keywordflow">if</font>( EQUALN(pszResampling,<font class="stringliteral">"AVER"</font>,4) && nOverviews > 1 )
00427 <font class="keywordflow">return</font> GDALRegenerateCascadingOverviews( poSrcBand,
00428 nOverviews, papoOvrBands,
00429 pszResampling,
00430 pfnProgress,
00431 pProgressData );
00432
00433 <font class="comment">/* -------------------------------------------------------------------- */</font>
00434 <font class="comment">/* Setup one horizontal swath to read from the raw buffer. */</font>
00435 <font class="comment">/* -------------------------------------------------------------------- */</font>
00436 <font class="keywordtype">float</font> *pafChunk;
00437
00438 poSrcBand-><a class="code" href="class_GDALRasterBand.html#a6">GetBlockSize</a>( &nFRXBlockSize, &nFRYBlockSize );
00439
00440 <font class="keywordflow">if</font>( nFRYBlockSize < 4 || nFRYBlockSize > 256 )
00441 nFullResYChunk = 32;
00442 <font class="keywordflow">else</font>
00443 nFullResYChunk = nFRYBlockSize;
00444
00445 <font class="keywordflow">if</font>( GDALDataTypeIsComplex( poSrcBand-><a class="code" href="class_GDALRasterBand.html#a5">GetRasterDataType</a>() ) )
00446 eType = GDT_CFloat32;
00447 <font class="keywordflow">else</font>
00448 eType = GDT_Float32;
00449
00450 nWidth = poSrcBand-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>();
00451 pafChunk = (<font class="keywordtype">float</font> *)
00452 VSIMalloc((GDALGetDataTypeSize(eType)/8) * nFullResYChunk * nWidth );
00453
00454 <font class="keywordflow">if</font>( pafChunk == NULL )
00455 {
00456 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_OutOfMemory,
00457 <font class="stringliteral">"Out of memory in GDALRegenerateOverviews()."</font> );
00458
00459 <font class="keywordflow">return</font> CE_Failure;
00460 }
00461
00462 <font class="comment">/* -------------------------------------------------------------------- */</font>
00463 <font class="comment">/* Loop over image operating on chunks. */</font>
00464 <font class="comment">/* -------------------------------------------------------------------- */</font>
00465 <font class="keywordtype">int</font> nChunkYOff = 0;
00466
00467 <font class="keywordflow">for</font>( nChunkYOff = 0;
00468 nChunkYOff < poSrcBand->GetYSize();
00469 nChunkYOff += nFullResYChunk )
00470 {
00471 <font class="keywordflow">if</font>( !pfnProgress( nChunkYOff / (<font class="keywordtype">double</font>) poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>(),
00472 NULL, pProgressData ) )
00473 {
00474 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_UserInterrupt, <font class="stringliteral">"User terminated"</font> );
00475 <font class="keywordflow">return</font> CE_Failure;
00476 }
00477
00478 <font class="keywordflow">if</font>( nFullResYChunk + nChunkYOff > poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>() )
00479 nFullResYChunk = poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>() - nChunkYOff;
00480
00481 <font class="comment">/* read chunk */</font>
00482 poSrcBand-><a class="code" href="class_GDALRasterBand.html#a8">RasterIO</a>( GF_Read, 0, nChunkYOff, nWidth, nFullResYChunk,
00483 pafChunk, nWidth, nFullResYChunk, eType,
00484 0, 0 );
00485
00486 <font class="keywordflow">for</font>( <font class="keywordtype">int</font> iOverview = 0; iOverview < nOverviews; iOverview++ )
00487 {
00488 <font class="keywordflow">if</font>( eType == GDT_Float32 )
00489 GDALDownsampleChunk32R(nWidth, poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>(),
00490 pafChunk, nChunkYOff, nFullResYChunk,
00491 papoOvrBands[iOverview], pszResampling);
00492 <font class="keywordflow">else</font>
00493 GDALDownsampleChunkC32R(nWidth, poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>(),
00494 pafChunk, nChunkYOff, nFullResYChunk,
00495 papoOvrBands[iOverview], pszResampling);
00496 }
00497 }
00498
00499 VSIFree( pafChunk );
00500
00501 <font class="comment">/* -------------------------------------------------------------------- */</font>
00502 <font class="comment">/* Renormalized overview mean / stddev if needed. */</font>
00503 <font class="comment">/* -------------------------------------------------------------------- */</font>
00504 <font class="keywordflow">if</font>( EQUAL(pszResampling,<font class="stringliteral">"AVERAGE_MP"</font>) )
00505 {
00506 GDALOverviewMagnitudeCorrection( (GDALRasterBandH) poSrcBand,
00507 nOverviews,
00508 (GDALRasterBandH *) papoOvrBands,
00509 GDALDummyProgress, NULL );
00510 }
00511
00512 <font class="comment">/* -------------------------------------------------------------------- */</font>
00513 <font class="comment">/* It can be important to flush out data to overviews. */</font>
00514 <font class="comment">/* -------------------------------------------------------------------- */</font>
00515 <font class="keywordflow">for</font>( <font class="keywordtype">int</font> iOverview = 0; iOverview < nOverviews; iOverview++ )
00516 papoOvrBands[iOverview]-><a class="code" href="class_GDALRasterBand.html#a12">FlushCache</a>();
00517
00518 pfnProgress( 1.0, NULL, pProgressData );
00519
00520 <font class="keywordflow">return</font> CE_None;
00521 }
00522
00523 <font class="comment">/************************************************************************/</font>
00524 <font class="comment">/* GDALComputeBandStats() */</font>
00525 <font class="comment">/************************************************************************/</font>
00526
00527 CPLErr
00528 GDALComputeBandStats( GDALRasterBandH hSrcBand,
00529 <font class="keywordtype">int</font> nSampleStep,
00530 <font class="keywordtype">double</font> *pdfMean, <font class="keywordtype">double</font> *pdfStdDev,
00531 GDALProgressFunc pfnProgress,
00532 <font class="keywordtype">void</font> *pProgressData )<font class="keyword"></font>
00533 <font class="keyword"></font>
00534 <font class="keyword"></font>{
00535 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poSrcBand = (<a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *) hSrcBand;
00536 <font class="keywordtype">int</font> iLine, nWidth, nHeight;
00537 GDALDataType eType = poSrcBand-><a class="code" href="class_GDALRasterBand.html#a5">GetRasterDataType</a>();
00538 GDALDataType eWrkType;
00539 <font class="keywordtype">int</font> bComplex;
00540 <font class="keywordtype">float</font> *pafData;
00541 <font class="keywordtype">double</font> dfSum=0.0, dfSum2=0.0;
00542 <font class="keywordtype">int</font> nSamples = 0;
00543
00544 nWidth = poSrcBand-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>();
00545 nHeight = poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00546
00547 <font class="keywordflow">if</font>( nSampleStep >= nHeight )
00548 nSampleStep = 1;
00549
00550 bComplex = GDALDataTypeIsComplex(eType);
00551 <font class="keywordflow">if</font>( bComplex )
00552 {
00553 pafData = (<font class="keywordtype">float</font> *) <a class="code" href="cpl_conv_h.html#a3">CPLMalloc</a>(nWidth * 2 * <font class="keyword">sizeof</font>(<font class="keywordtype">float</font>));
00554 eWrkType = GDT_CFloat32;
00555 }
00556 <font class="keywordflow">else</font>
00557 {
00558 pafData = (<font class="keywordtype">float</font> *) <a class="code" href="cpl_conv_h.html#a3">CPLMalloc</a>(nWidth * <font class="keyword">sizeof</font>(<font class="keywordtype">float</font>));
00559 eWrkType = GDT_Float32;
00560 }
00561
00562 <font class="comment">/* -------------------------------------------------------------------- */</font>
00563 <font class="comment">/* Loop over all sample lines. */</font>
00564 <font class="comment">/* -------------------------------------------------------------------- */</font>
00565 <font class="keywordflow">for</font>( iLine = 0; iLine < nHeight; iLine += nSampleStep )
00566 {
00567 <font class="keywordtype">int</font> iPixel;
00568
00569 <font class="keywordflow">if</font>( !pfnProgress( iLine / (<font class="keywordtype">double</font>) nHeight,
00570 NULL, pProgressData ) )
00571 {
00572 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_UserInterrupt, <font class="stringliteral">"User terminated"</font> );
00573 CPLFree( pafData );
00574 <font class="keywordflow">return</font> CE_Failure;
00575 }
00576
00577 poSrcBand-><a class="code" href="class_GDALRasterBand.html#a8">RasterIO</a>( GF_Read, 0, iLine, nWidth, 1,
00578 pafData, nWidth, 1, eWrkType,
00579 0, 0 );
00580
00581 <font class="keywordflow">for</font>( iPixel = 0; iPixel < nWidth; iPixel++ )
00582 {
00583 <font class="keywordtype">float</font> fValue;
00584
00585 <font class="keywordflow">if</font>( bComplex )
00586 {
00587 <font class="comment">// Compute the magnitude of the complex value.</font>
00588
00589 fValue = sqrt(pafData[iPixel*2 ] * pafData[iPixel*2 ]
00590 + pafData[iPixel*2+1] * pafData[iPixel*2+1]);
00591 }
00592 <font class="keywordflow">else</font>
00593 {
00594 fValue = pafData[iPixel];
00595 }
00596
00597 dfSum += fValue;
00598 dfSum2 += fValue * fValue;
00599 }
00600
00601 nSamples += nWidth;
00602 }
00603
00604 <font class="keywordflow">if</font>( !pfnProgress( 1.0, NULL, pProgressData ) )
00605 {
00606 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_UserInterrupt, <font class="stringliteral">"User terminated"</font> );
00607 CPLFree( pafData );
00608 <font class="keywordflow">return</font> CE_Failure;
00609 }
00610
00611 <font class="comment">/* -------------------------------------------------------------------- */</font>
00612 <font class="comment">/* Produce the result values. */</font>
00613 <font class="comment">/* -------------------------------------------------------------------- */</font>
00614 <font class="keywordflow">if</font>( pdfMean != NULL )
00615 *pdfMean = dfSum / nSamples;
00616
00617 <font class="keywordflow">if</font>( pdfStdDev != NULL )
00618 {
00619 <font class="keywordtype">double</font> dfMean = dfSum / nSamples;
00620
00621 *pdfStdDev = sqrt((dfSum2 / nSamples) - (dfMean * dfMean));
00622 }
00623
00624 CPLFree( pafData );
00625
00626 <font class="keywordflow">return</font> CE_None;
00627 }
00628
00629 <font class="comment">/************************************************************************/</font>
00630 <font class="comment">/* GDALOverviewMagnitudeCorrection() */</font>
00631 <font class="comment">/* */</font>
00632 <font class="comment">/* Correct the mean and standard deviation of the overviews of */</font>
00633 <font class="comment">/* the given band to match the base layer approximately. */</font>
00634 <font class="comment">/************************************************************************/</font>
00635
00636 CPLErr
00637 GDALOverviewMagnitudeCorrection( GDALRasterBandH hBaseBand,
00638 <font class="keywordtype">int</font> nOverviewCount,
00639 GDALRasterBandH *pahOverviews,
00640 GDALProgressFunc pfnProgress,
00641 <font class="keywordtype">void</font> *pProgressData )<font class="keyword"></font>
00642 <font class="keyword"></font>
00643 <font class="keyword"></font>{
00644 CPLErr eErr;
00645 <font class="keywordtype">double</font> dfOrigMean, dfOrigStdDev;
00646
00647 <font class="comment">/* -------------------------------------------------------------------- */</font>
00648 <font class="comment">/* Compute mean/stddev for source raster. */</font>
00649 <font class="comment">/* -------------------------------------------------------------------- */</font>
00650 eErr = GDALComputeBandStats( hBaseBand, 2, &dfOrigMean, &dfOrigStdDev,
00651 pfnProgress, pProgressData );
00652
00653 <font class="keywordflow">if</font>( eErr != CE_None )
00654 <font class="keywordflow">return</font> eErr;
00655
00656 <font class="comment">/* -------------------------------------------------------------------- */</font>
00657 <font class="comment">/* Loop on overview bands. */</font>
00658 <font class="comment">/* -------------------------------------------------------------------- */</font>
00659 <font class="keywordtype">int</font> iOverview;
00660
00661 <font class="keywordflow">for</font>( iOverview = 0; iOverview < nOverviewCount; iOverview++ )
00662 {
00663 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poOverview = (<a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *)pahOverviews[iOverview];
00664 <font class="keywordtype">double</font> dfOverviewMean, dfOverviewStdDev;
00665 <font class="keywordtype">double</font> dfGain;
00666
00667 eErr = GDALComputeBandStats( pahOverviews[iOverview], 1,
00668 &dfOverviewMean, &dfOverviewStdDev,
00669 pfnProgress, pProgressData );
00670
00671 <font class="keywordflow">if</font>( eErr != CE_None )
00672 <font class="keywordflow">return</font> eErr;
00673
00674 <font class="keywordflow">if</font>( dfOrigStdDev < 0.0001 )
00675 dfGain = 1.0;
00676 <font class="keywordflow">else</font>
00677 dfGain = dfOrigStdDev / dfOverviewStdDev;
00678
00679 <font class="comment">/* -------------------------------------------------------------------- */</font>
00680 <font class="comment">/* Apply gain and offset. */</font>
00681 <font class="comment">/* -------------------------------------------------------------------- */</font>
00682 GDALDataType eWrkType, eType = poOverview-><a class="code" href="class_GDALRasterBand.html#a5">GetRasterDataType</a>();
00683 <font class="keywordtype">int</font> iLine, nWidth, nHeight, bComplex;
00684 <font class="keywordtype">float</font> *pafData;
00685
00686 nWidth = poOverview-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>();
00687 nHeight = poOverview-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00688
00689 bComplex = GDALDataTypeIsComplex(eType);
00690 <font class="keywordflow">if</font>( bComplex )
00691 {
00692 pafData = (<font class="keywordtype">float</font> *) <a class="code" href="cpl_conv_h.html#a3">CPLMalloc</a>(nWidth * 2 * <font class="keyword">sizeof</font>(<font class="keywordtype">float</font>));
00693 eWrkType = GDT_CFloat32;
00694 }
00695 <font class="keywordflow">else</font>
00696 {
00697 pafData = (<font class="keywordtype">float</font> *) <a class="code" href="cpl_conv_h.html#a3">CPLMalloc</a>(nWidth * <font class="keyword">sizeof</font>(<font class="keywordtype">float</font>));
00698 eWrkType = GDT_Float32;
00699 }
00700
00701 <font class="keywordflow">for</font>( iLine = 0; iLine < nHeight; iLine++ )
00702 {
00703 <font class="keywordtype">int</font> iPixel;
00704
00705 <font class="keywordflow">if</font>( !pfnProgress( iLine / (<font class="keywordtype">double</font>) nHeight,
00706 NULL, pProgressData ) )
00707 {
00708 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_UserInterrupt, <font class="stringliteral">"User terminated"</font> );
00709 CPLFree( pafData );
00710 <font class="keywordflow">return</font> CE_Failure;
00711 }
00712
00713 poOverview-><a class="code" href="class_GDALRasterBand.html#a8">RasterIO</a>( GF_Read, 0, iLine, nWidth, 1,
00714 pafData, nWidth, 1, eWrkType,
00715 0, 0 );
00716
00717 <font class="keywordflow">for</font>( iPixel = 0; iPixel < nWidth; iPixel++ )
00718 {
00719 <font class="keywordflow">if</font>( bComplex )
00720 {
00721 pafData[iPixel*2] *= dfGain;
00722 pafData[iPixel*2+1] *= dfGain;
00723 }
00724 <font class="keywordflow">else</font>
00725 {
00726 pafData[iPixel] = (pafData[iPixel]-dfOverviewMean)*dfGain
00727 + dfOrigMean;
00728
00729 }
00730 }
00731
00732 poOverview-><a class="code" href="class_GDALRasterBand.html#a8">RasterIO</a>( GF_Write, 0, iLine, nWidth, 1,
00733 pafData, nWidth, 1, eWrkType,
00734 0, 0 );
00735 }
00736
00737 <font class="keywordflow">if</font>( !pfnProgress( 1.0, NULL, pProgressData ) )
00738 {
00739 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_UserInterrupt, <font class="stringliteral">"User terminated"</font> );
00740 CPLFree( pafData );
00741 <font class="keywordflow">return</font> CE_Failure;
00742 }
00743
00744 CPLFree( pafData );
00745 }
00746
00747 <font class="keywordflow">return</font> CE_None;
00748 }
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