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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 1.13 2002/12/21 19:13:13 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 1.13 2002/12/21 19:13:13 warmerda
00030 <font class="comment"> * updated
00030 <font class="comment"> *</font>
00031 <font class="comment"> * Revision 1.10 2002/07/09 20:33:12 warmerda</font>
00032 <font class="comment"> * expand tabs</font>
00033 <font class="comment"> *</font>
00034 <font class="comment"> * Revision 1.9 2002/04/16 17:49:29 warmerda</font>
00035 <font class="comment"> * Ensure dfRatio is assigned a value.</font>
00036 <font class="comment"> *</font>
00037 <font class="comment"> * Revision 1.8 2001/07/18 04:04:30 warmerda</font>
00038 <font class="comment"> * added CPL_CVSID</font>
00039 <font class="comment"> *</font>
00040 <font class="comment"> * Revision 1.7 2001/07/16 15:21:46 warmerda</font>
00041 <font class="comment"> * added AVERAGE_MAGPHASE option for complex images</font>
00042 <font class="comment"> *</font>
00043 <font class="comment"> * Revision 1.6 2001/01/30 22:32:42 warmerda</font>
00044 <font class="comment"> * added AVERAGE_MP (magnitude preserving averaging) overview resampling type</font>
00045 <font class="comment"> *</font>
00046 <font class="comment"> * Revision 1.5 2000/11/22 18:41:45 warmerda</font>
00047 <font class="comment"> * fixed bug in complex overview generation</font>
00048 <font class="comment"> *</font>
00049 <font class="comment"> * Revision 1.4 2000/08/18 15:25:06 warmerda</font>
00050 <font class="comment"> * added cascading overview regeneration to speed up averaged overviews</font>
00051 <font class="comment"> *</font>
00052 <font class="comment"> * Revision 1.3 2000/07/17 17:08:45 warmerda</font>
00053 <font class="comment"> * added support for complex data</font>
00054 <font class="comment"> *</font>
00055 <font class="comment"> * Revision 1.2 2000/06/26 22:17:58 warmerda</font>
00056 <font class="comment"> * added scaled progress support</font>
00057 <font class="comment"> *</font>
00058 <font class="comment"> * Revision 1.1 2000/04/21 21:54:05 warmerda</font>
00059 <font class="comment"> * New</font>
00060 <font class="comment"> *</font>
00061 <font class="comment"> */</font>
00062
00063 <font class="preprocessor">#include "gdal_priv.h"</font>
00064
00065 CPL_CVSID(<font class="stringliteral">"$Id: overview_cpp-source.html,v 1.13 2002/12/21 19:13:13 warmerda Exp $"</font>);
00066
00067 <font class="comment">/************************************************************************/</font>
00068 <font class="comment">/* GDALDownsampleChunk32R() */</font>
00069 <font class="comment">/************************************************************************/</font>
00070
00071 <font class="keyword">static</font> CPLErr
00072 GDALDownsampleChunk32R( <font class="keywordtype">int</font> nSrcWidth, <font class="keywordtype">int</font> nSrcHeight,
00073 <font class="keywordtype">float</font> * pafChunk, <font class="keywordtype">int</font> nChunkYOff, <font class="keywordtype">int</font> nChunkYSize,
00074 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> * poOverview,
00075 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszResampling )<font class="keyword"></font>
00076 <font class="keyword"></font>
00077 <font class="keyword"></font>{
00078 <font class="keywordtype">int</font> nDstYOff, nDstYOff2, nOXSize, nOYSize;
00079 <font class="keywordtype">float</font> *pafDstScanline;
00080
00081 nOXSize = poOverview-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>();
00082 nOYSize = poOverview-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00083
00084 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>));
00085
00086 <font class="comment">/* -------------------------------------------------------------------- */</font>
00087 <font class="comment">/* Figure out the line to start writing to, and the first line */</font>
00088 <font class="comment">/* to not write to. In theory this approach should ensure that */</font>
00089 <font class="comment">/* every output line will be written if all input chunks are */</font>
00090 <font class="comment">/* processed. */</font>
00091 <font class="comment">/* -------------------------------------------------------------------- */</font>
00092 nDstYOff = (<font class="keywordtype">int</font>) (0.5 + (nChunkYOff/(<font class="keywordtype">double</font>)nSrcHeight) * nOYSize);
00093 nDstYOff2 = (<font class="keywordtype">int</font>)
00094 (0.5 + ((nChunkYOff+nChunkYSize)/(<font class="keywordtype">double</font>)nSrcHeight) * nOYSize);
00095
00096 <font class="keywordflow">if</font>( nChunkYOff + nChunkYSize == nSrcHeight )
00097 nDstYOff2 = nOYSize;
00098
00099 <font class="comment">/* ==================================================================== */</font>
00100 <font class="comment">/* Loop over destination scanlines. */</font>
00101 <font class="comment">/* ==================================================================== */</font>
00102 <font class="keywordflow">for</font>( <font class="keywordtype">int</font> iDstLine = nDstYOff; iDstLine < nDstYOff2; iDstLine++ )
00103 {
00104 <font class="keywordtype">float</font> *pafSrcScanline;
00105 <font class="keywordtype">int</font> nSrcYOff, nSrcYOff2, iDstPixel;
00106
00107 nSrcYOff = (<font class="keywordtype">int</font>) (0.5 + (iDstLine/(<font class="keywordtype">double</font>)nOYSize) * nSrcHeight);
00108 <font class="keywordflow">if</font>( nSrcYOff < nChunkYOff )
00109 nSrcYOff = nChunkYOff;
00110
00111 nSrcYOff2 = (<font class="keywordtype">int</font>) (0.5 + ((iDstLine+1)/(<font class="keywordtype">double</font>)nOYSize) * nSrcHeight);
00112 <font class="keywordflow">if</font>( nSrcYOff2 > nSrcHeight || iDstLine == nOYSize-1 )
00113 nSrcYOff2 = nSrcHeight;
00114 <font class="keywordflow">if</font>( nSrcYOff2 > nChunkYOff + nChunkYSize )
00115 nSrcYOff2 = nChunkYOff + nChunkYSize;
00116
00117 pafSrcScanline = pafChunk + ((nSrcYOff-nChunkYOff) * nSrcWidth);
00118
00119 <font class="comment">/* -------------------------------------------------------------------- */</font>
00120 <font class="comment">/* Loop over destination pixels */</font>
00121 <font class="comment">/* -------------------------------------------------------------------- */</font>
00122 <font class="keywordflow">for</font>( iDstPixel = 0; iDstPixel < nOXSize; iDstPixel++ )
00123 {
00124 <font class="keywordtype">int</font> nSrcXOff, nSrcXOff2;
00125
00126 nSrcXOff = (<font class="keywordtype">int</font>) (0.5 + (iDstPixel/(<font class="keywordtype">double</font>)nOXSize) * nSrcWidth);
00127 nSrcXOff2 = (<font class="keywordtype">int</font>)
00128 (0.5 + ((iDstPixel+1)/(<font class="keywordtype">double</font>)nOXSize) * nSrcWidth);
00129 <font class="keywordflow">if</font>( nSrcXOff2 > nSrcWidth )
00130 nSrcXOff2 = nSrcWidth;
00131
00132 <font class="keywordflow">if</font>( EQUALN(pszResampling,<font class="stringliteral">"NEAR"</font>,4) )
00133 {
00134 pafDstScanline[iDstPixel] = pafSrcScanline[nSrcXOff];
00135 }
00136 <font class="keywordflow">else</font> <font class="keywordflow">if</font>( EQUALN(pszResampling,<font class="stringliteral">"AVER"</font>,4) )
00137 {
00138 <font class="keywordtype">double</font> dfTotal = 0.0;
00139 <font class="keywordtype">int</font> nCount = 0, iX, iY;
00140
00141 <font class="keywordflow">for</font>( iY = nSrcYOff; iY < nSrcYOff2; iY++ )
00142 {
00143 <font class="keywordflow">for</font>( iX = nSrcXOff; iX < nSrcXOff2; iX++ )
00144 {
00145 dfTotal += pafSrcScanline[iX+(iY-nSrcYOff)*nSrcWidth];
00146 nCount++;
00147 }
00148 }
00149
00150 CPLAssert( nCount > 0 );
00151 <font class="keywordflow">if</font>( nCount == 0 )
00152 {
00153 pafDstScanline[iDstPixel] = 0.0;
00154 }
00155 <font class="keywordflow">else</font>
00156 pafDstScanline[iDstPixel] = dfTotal / nCount;
00157 }
00158 }
00159
00160 poOverview-><a class="code" href="class_GDALRasterBand.html#a9">RasterIO</a>( GF_Write, 0, iDstLine, nOXSize, 1,
00161 pafDstScanline, nOXSize, 1, GDT_Float32,
00162 0, 0 );
00163 }
00164
00165 CPLFree( pafDstScanline );
00166
00167 <font class="keywordflow">return</font> CE_None;
00168 }
00169
00170 <font class="comment">/************************************************************************/</font>
00171 <font class="comment">/* GDALDownsampleChunkC32R() */</font>
00172 <font class="comment">/************************************************************************/</font>
00173
00174 <font class="keyword">static</font> CPLErr
00175 GDALDownsampleChunkC32R( <font class="keywordtype">int</font> nSrcWidth, <font class="keywordtype">int</font> nSrcHeight,
00176 <font class="keywordtype">float</font> * pafChunk, <font class="keywordtype">int</font> nChunkYOff, <font class="keywordtype">int</font> nChunkYSize,
00177 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> * poOverview,
00178 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszResampling )<font class="keyword"></font>
00179 <font class="keyword"> </font>
00180 <font class="keyword"></font>{
00181 <font class="keywordtype">int</font> nDstYOff, nDstYOff2, nOXSize, nOYSize;
00182 <font class="keywordtype">float</font> *pafDstScanline;
00183
00184 nOXSize = poOverview-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>();
00185 nOYSize = poOverview-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00186
00187 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);
00188
00189 <font class="comment">/* -------------------------------------------------------------------- */</font>
00190 <font class="comment">/* Figure out the line to start writing to, and the first line */</font>
00191 <font class="comment">/* to not write to. In theory this approach should ensure that */</font>
00192 <font class="comment">/* every output line will be written if all input chunks are */</font>
00193 <font class="comment">/* processed. */</font>
00194 <font class="comment">/* -------------------------------------------------------------------- */</font>
00195 nDstYOff = (<font class="keywordtype">int</font>) (0.5 + (nChunkYOff/(<font class="keywordtype">double</font>)nSrcHeight) * nOYSize);
00196 nDstYOff2 = (<font class="keywordtype">int</font>)
00197 (0.5 + ((nChunkYOff+nChunkYSize)/(<font class="keywordtype">double</font>)nSrcHeight) * nOYSize);
00198
00199 <font class="keywordflow">if</font>( nChunkYOff + nChunkYSize == nSrcHeight )
00200 nDstYOff2 = nOYSize;
00201
00202 <font class="comment">/* ==================================================================== */</font>
00203 <font class="comment">/* Loop over destination scanlines. */</font>
00204 <font class="comment">/* ==================================================================== */</font>
00205 <font class="keywordflow">for</font>( <font class="keywordtype">int</font> iDstLine = nDstYOff; iDstLine < nDstYOff2; iDstLine++ )
00206 {
00207 <font class="keywordtype">float</font> *pafSrcScanline;
00208 <font class="keywordtype">int</font> nSrcYOff, nSrcYOff2, iDstPixel;
00209
00210 nSrcYOff = (<font class="keywordtype">int</font>) (0.5 + (iDstLine/(<font class="keywordtype">double</font>)nOYSize) * nSrcHeight);
00211 <font class="keywordflow">if</font>( nSrcYOff < nChunkYOff )
00212 nSrcYOff = nChunkYOff;
00213
00214 nSrcYOff2 = (<font class="keywordtype">int</font>) (0.5 + ((iDstLine+1)/(<font class="keywordtype">double</font>)nOYSize) * nSrcHeight);
00215 <font class="keywordflow">if</font>( nSrcYOff2 > nSrcHeight || iDstLine == nOYSize-1 )
00216 nSrcYOff2 = nSrcHeight;
00217 <font class="keywordflow">if</font>( nSrcYOff2 > nChunkYOff + nChunkYSize )
00218 nSrcYOff2 = nChunkYOff + nChunkYSize;
00219
00220 pafSrcScanline = pafChunk + ((nSrcYOff-nChunkYOff) * nSrcWidth) * 2;
00221
00222 <font class="comment">/* -------------------------------------------------------------------- */</font>
00223 <font class="comment">/* Loop over destination pixels */</font>
00224 <font class="comment">/* -------------------------------------------------------------------- */</font>
00225 <font class="keywordflow">for</font>( iDstPixel = 0; iDstPixel < nOXSize; iDstPixel++ )
00226 {
00227 <font class="keywordtype">int</font> nSrcXOff, nSrcXOff2;
00228
00229 nSrcXOff = (<font class="keywordtype">int</font>) (0.5 + (iDstPixel/(<font class="keywordtype">double</font>)nOXSize) * nSrcWidth);
00230 nSrcXOff2 = (<font class="keywordtype">int</font>)
00231 (0.5 + ((iDstPixel+1)/(<font class="keywordtype">double</font>)nOXSize) * nSrcWidth);
00232 <font class="keywordflow">if</font>( nSrcXOff2 > nSrcWidth )
00233 nSrcXOff2 = nSrcWidth;
00234
00235 <font class="keywordflow">if</font>( EQUALN(pszResampling,<font class="stringliteral">"NEAR"</font>,4) )
00236 {
00237 pafDstScanline[iDstPixel*2] = pafSrcScanline[nSrcXOff*2];
00238 pafDstScanline[iDstPixel*2+1] = pafSrcScanline[nSrcXOff*2+1];
00239 }
00240 <font class="keywordflow">else</font> <font class="keywordflow">if</font>( EQUAL(pszResampling,<font class="stringliteral">"AVERAGE_MAGPHASE"</font>) )
00241 {
00242 <font class="keywordtype">double</font> dfTotalR = 0.0, dfTotalI = 0.0, dfTotalM = 0.0;
00243 <font class="keywordtype">int</font> nCount = 0, iX, iY;
00244
00245 <font class="keywordflow">for</font>( iY = nSrcYOff; iY < nSrcYOff2; iY++ )
00246 {
00247 <font class="keywordflow">for</font>( iX = nSrcXOff; iX < nSrcXOff2; iX++ )
00248 {
00249 <font class="keywordtype">double</font> dfR, dfI;
00250
00251 dfR = pafSrcScanline[iX*2+(iY-nSrcYOff)*nSrcWidth*2];
00252 dfI = pafSrcScanline[iX*2+(iY-nSrcYOff)*nSrcWidth*2+1];
00253 dfTotalR += dfR;
00254 dfTotalI += dfI;
00255 dfTotalM += sqrt( dfR*dfR + dfI*dfI );
00256 nCount++;
00257 }
00258 }
00259
00260 CPLAssert( nCount > 0 );
00261 <font class="keywordflow">if</font>( nCount == 0 )
00262 {
00263 pafDstScanline[iDstPixel*2] = 0.0;
00264 pafDstScanline[iDstPixel*2+1] = 0.0;
00265 }
00266 <font class="keywordflow">else</font>
00267 {
00268 <font class="keywordtype">double</font> dfM, dfDesiredM, dfRatio=1.0;
00269
00270 pafDstScanline[iDstPixel*2 ] = dfTotalR / nCount;
00271 pafDstScanline[iDstPixel*2+1] = dfTotalI / nCount;
00272
00273 dfM = sqrt(pafDstScanline[iDstPixel*2 ]*pafDstScanline[iDstPixel*2 ]
00274 + pafDstScanline[iDstPixel*2+1]*pafDstScanline[iDstPixel*2+1]);
00275 dfDesiredM = dfTotalM / nCount;
00276 <font class="keywordflow">if</font>( dfM != 0.0 )
00277 dfRatio = dfDesiredM / dfM;
00278
00279 pafDstScanline[iDstPixel*2 ] *= dfRatio;
00280 pafDstScanline[iDstPixel*2+1] *= dfRatio;
00281 }
00282 }
00283 <font class="keywordflow">else</font> <font class="keywordflow">if</font>( EQUALN(pszResampling,<font class="stringliteral">"AVER"</font>,4) )
00284 {
00285 <font class="keywordtype">double</font> dfTotalR = 0.0, dfTotalI = 0.0;
00286 <font class="keywordtype">int</font> nCount = 0, iX, iY;
00287
00288 <font class="keywordflow">for</font>( iY = nSrcYOff; iY < nSrcYOff2; iY++ )
00289 {
00290 <font class="keywordflow">for</font>( iX = nSrcXOff; iX < nSrcXOff2; iX++ )
00291 {
00292 dfTotalR += pafSrcScanline[iX*2+(iY-nSrcYOff)*nSrcWidth*2];
00293 dfTotalI += pafSrcScanline[iX*2+(iY-nSrcYOff)*nSrcWidth*2+1];
00294 nCount++;
00295 }
00296 }
00297
00298 CPLAssert( nCount > 0 );
00299 <font class="keywordflow">if</font>( nCount == 0 )
00300 {
00301 pafDstScanline[iDstPixel*2] = 0.0;
00302 pafDstScanline[iDstPixel*2+1] = 0.0;
00303 }
00304 <font class="keywordflow">else</font>
00305 {
00306 pafDstScanline[iDstPixel*2 ] = dfTotalR / nCount;
00307 pafDstScanline[iDstPixel*2+1] = dfTotalI / nCount;
00308 }
00309 }
00310 }
00311
00312 poOverview-><a class="code" href="class_GDALRasterBand.html#a9">RasterIO</a>( GF_Write, 0, iDstLine, nOXSize, 1,
00313 pafDstScanline, nOXSize, 1, GDT_CFloat32,
00314 0, 0 );
00315 }
00316
00317 CPLFree( pafDstScanline );
00318
00319 <font class="keywordflow">return</font> CE_None;
00320 }
00321
00322 <font class="comment">/************************************************************************/</font>
00323 <font class="comment">/* GDALRegenerateCascadingOverviews() */</font>
00324 <font class="comment">/* */</font>
00325 <font class="comment">/* Generate a list of overviews in order from largest to */</font>
00326 <font class="comment">/* smallest, computing each from the next larger. */</font>
00327 <font class="comment">/************************************************************************/</font>
00328
00329 <font class="keyword">static</font> CPLErr
00330 GDALRegenerateCascadingOverviews(
00331 <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,
00332 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszResampling,
00333 GDALProgressFunc pfnProgress, <font class="keywordtype">void</font> * pProgressData )<font class="keyword"></font>
00334 <font class="keyword"></font>
00335 <font class="keyword"></font>{
00336 <font class="comment">/* -------------------------------------------------------------------- */</font>
00337 <font class="comment">/* First, we must put the overviews in order from largest to */</font>
00338 <font class="comment">/* smallest. */</font>
00339 <font class="comment">/* -------------------------------------------------------------------- */</font>
00340 <font class="keywordtype">int</font> i, j;
00341
00342 <font class="keywordflow">for</font>( i = 0; i < nOverviews-1; i++ )
00343 {
00344 <font class="keywordflow">for</font>( j = 0; j < nOverviews - i - 1; j++ )
00345 {
00346
00347 <font class="keywordflow">if</font>( papoOvrBands[j]-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>()
00348 * (<font class="keywordtype">float</font>) papoOvrBands[j]-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>() <
00349 papoOvrBands[j+1]-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>()
00350 * (<font class="keywordtype">float</font>) papoOvrBands[j+1]-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>() )
00351 {
00352 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> * poTempBand;
00353
00354 poTempBand = papoOvrBands[j];
00355 papoOvrBands[j] = papoOvrBands[j+1];
00356 papoOvrBands[j+1] = poTempBand;
00357 }
00358 }
00359 }
00360
00361 <font class="comment">/* -------------------------------------------------------------------- */</font>
00362 <font class="comment">/* Count total pixels so we can prepare appropriate scaled */</font>
00363 <font class="comment">/* progress functions. */</font>
00364 <font class="comment">/* -------------------------------------------------------------------- */</font>
00365 <font class="keywordtype">double</font> dfTotalPixels = 0.0;
00366
00367 <font class="keywordflow">for</font>( i = 0; i < nOverviews; i++ )
00368 {
00369 dfTotalPixels += papoOvrBands[i]-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>()
00370 * (<font class="keywordtype">double</font>) papoOvrBands[i]-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00371 }
00372
00373 <font class="comment">/* -------------------------------------------------------------------- */</font>
00374 <font class="comment">/* Generate all the bands. */</font>
00375 <font class="comment">/* -------------------------------------------------------------------- */</font>
00376 <font class="keywordtype">double</font> dfPixelsProcessed = 0.0;
00377
00378 <font class="keywordflow">for</font>( i = 0; i < nOverviews; i++ )
00379 {
00380 <font class="keywordtype">void</font> *pScaledProgressData;
00381 <font class="keywordtype">double</font> dfPixels;
00382 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poBaseBand;
00383 CPLErr eErr;
00384
00385 <font class="keywordflow">if</font>( i == 0 )
00386 poBaseBand = poSrcBand;
00387 <font class="keywordflow">else</font>
00388 poBaseBand = papoOvrBands[i-1];
00389
00390 dfPixels = papoOvrBands[i]-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>()
00391 * (<font class="keywordtype">double</font>) papoOvrBands[i]-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00392
00393 pScaledProgressData = GDALCreateScaledProgress(
00394 dfPixelsProcessed / dfTotalPixels,
00395 (dfPixelsProcessed + dfPixels) / dfTotalPixels,
00396 pfnProgress, pProgressData );
00397
00398 eErr = GDALRegenerateOverviews( poBaseBand, 1, papoOvrBands + i,
00399 pszResampling,
00400 GDALScaledProgress,
00401 pScaledProgressData );
00402 GDALDestroyScaledProgress( pScaledProgressData );
00403
00404 <font class="keywordflow">if</font>( eErr != CE_None )
00405 <font class="keywordflow">return</font> eErr;
00406
00407 dfPixelsProcessed += dfPixels;
00408 }
00409
00410 <font class="keywordflow">return</font> CE_None;
00411 }
00412
00413 <font class="comment">/************************************************************************/</font>
00414 <font class="comment">/* GDALRegenerateOverviews() */</font>
00415 <font class="comment">/************************************************************************/</font>
00416 CPLErr
00417 GDALRegenerateOverviews( <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poSrcBand,
00418 <font class="keywordtype">int</font> nOverviews, <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> **papoOvrBands,
00419 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszResampling,
00420 GDALProgressFunc pfnProgress, <font class="keywordtype">void</font> * pProgressData )<font class="keyword"></font>
00421 <font class="keyword"></font>
00422 <font class="keyword"></font>{
00423 <font class="keywordtype">int</font> nFullResYChunk, nWidth;
00424 <font class="keywordtype">int</font> nFRXBlockSize, nFRYBlockSize;
00425 GDALDataType eType;
00426
00427 <font class="comment">/* -------------------------------------------------------------------- */</font>
00428 <font class="comment">/* If we are operating on multiple overviews, and using */</font>
00429 <font class="comment">/* averaging, lets do them in cascading order to reduce the */</font>
00430 <font class="comment">/* amount of computation. */</font>
00431 <font class="comment">/* -------------------------------------------------------------------- */</font>
00432 <font class="keywordflow">if</font>( EQUALN(pszResampling,<font class="stringliteral">"AVER"</font>,4) && nOverviews > 1 )
00433 <font class="keywordflow">return</font> GDALRegenerateCascadingOverviews( poSrcBand,
00434 nOverviews, papoOvrBands,
00435 pszResampling,
00436 pfnProgress,
00437 pProgressData );
00438
00439 <font class="comment">/* -------------------------------------------------------------------- */</font>
00440 <font class="comment">/* Setup one horizontal swath to read from the raw buffer. */</font>
00441 <font class="comment">/* -------------------------------------------------------------------- */</font>
00442 <font class="keywordtype">float</font> *pafChunk;
00443
00444 poSrcBand-><a class="code" href="class_GDALRasterBand.html#a7">GetBlockSize</a>( &nFRXBlockSize, &nFRYBlockSize );
00445
00446 <font class="keywordflow">if</font>( nFRYBlockSize < 4 || nFRYBlockSize > 256 )
00447 nFullResYChunk = 32;
00448 <font class="keywordflow">else</font>
00449 nFullResYChunk = nFRYBlockSize;
00450
00451 <font class="keywordflow">if</font>( GDALDataTypeIsComplex( poSrcBand-><a class="code" href="class_GDALRasterBand.html#a6">GetRasterDataType</a>() ) )
00452 eType = GDT_CFloat32;
00453 <font class="keywordflow">else</font>
00454 eType = GDT_Float32;
00455
00456 nWidth = poSrcBand-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>();
00457 pafChunk = (<font class="keywordtype">float</font> *)
00458 VSIMalloc((GDALGetDataTypeSize(eType)/8) * nFullResYChunk * nWidth );
00459
00460 <font class="keywordflow">if</font>( pafChunk == NULL )
00461 {
00462 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_OutOfMemory,
00463 <font class="stringliteral">"Out of memory in GDALRegenerateOverviews()."</font> );
00464
00465 <font class="keywordflow">return</font> CE_Failure;
00466 }
00467
00468 <font class="comment">/* -------------------------------------------------------------------- */</font>
00469 <font class="comment">/* Loop over image operating on chunks. */</font>
00470 <font class="comment">/* -------------------------------------------------------------------- */</font>
00471 <font class="keywordtype">int</font> nChunkYOff = 0;
00472
00473 <font class="keywordflow">for</font>( nChunkYOff = 0;
00474 nChunkYOff < poSrcBand->GetYSize();
00475 nChunkYOff += nFullResYChunk )
00476 {
00477 <font class="keywordflow">if</font>( !pfnProgress( nChunkYOff / (<font class="keywordtype">double</font>) poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>(),
00478 NULL, pProgressData ) )
00479 {
00480 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_UserInterrupt, <font class="stringliteral">"User terminated"</font> );
00481 <font class="keywordflow">return</font> CE_Failure;
00482 }
00483
00484 <font class="keywordflow">if</font>( nFullResYChunk + nChunkYOff > poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>() )
00485 nFullResYChunk = poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>() - nChunkYOff;
00486
00487 <font class="comment">/* read chunk */</font>
00488 poSrcBand-><a class="code" href="class_GDALRasterBand.html#a9">RasterIO</a>( GF_Read, 0, nChunkYOff, nWidth, nFullResYChunk,
00489 pafChunk, nWidth, nFullResYChunk, eType,
00490 0, 0 );
00491
00492 <font class="keywordflow">for</font>( <font class="keywordtype">int</font> iOverview = 0; iOverview < nOverviews; iOverview++ )
00493 {
00494 <font class="keywordflow">if</font>( eType == GDT_Float32 )
00495 GDALDownsampleChunk32R(nWidth, poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>(),
00496 pafChunk, nChunkYOff, nFullResYChunk,
00497 papoOvrBands[iOverview], pszResampling);
00498 <font class="keywordflow">else</font>
00499 GDALDownsampleChunkC32R(nWidth, poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>(),
00500 pafChunk, nChunkYOff, nFullResYChunk,
00501 papoOvrBands[iOverview], pszResampling);
00502 }
00503 }
00504
00505 VSIFree( pafChunk );
00506
00507 <font class="comment">/* -------------------------------------------------------------------- */</font>
00508 <font class="comment">/* Renormalized overview mean / stddev if needed. */</font>
00509 <font class="comment">/* -------------------------------------------------------------------- */</font>
00510 <font class="keywordflow">if</font>( EQUAL(pszResampling,<font class="stringliteral">"AVERAGE_MP"</font>) )
00511 {
00512 GDALOverviewMagnitudeCorrection( (GDALRasterBandH) poSrcBand,
00513 nOverviews,
00514 (GDALRasterBandH *) papoOvrBands,
00515 GDALDummyProgress, NULL );
00516 }
00517
00518 <font class="comment">/* -------------------------------------------------------------------- */</font>
00519 <font class="comment">/* It can be important to flush out data to overviews. */</font>
00520 <font class="comment">/* -------------------------------------------------------------------- */</font>
00521 <font class="keywordflow">for</font>( <font class="keywordtype">int</font> iOverview = 0; iOverview < nOverviews; iOverview++ )
00522 papoOvrBands[iOverview]-><a class="code" href="class_GDALRasterBand.html#a13">FlushCache</a>();
00523
00524 pfnProgress( 1.0, NULL, pProgressData );
00525
00526 <font class="keywordflow">return</font> CE_None;
00527 }
00528
00529 <font class="comment">/************************************************************************/</font>
00530 <font class="comment">/* GDALComputeBandStats() */</font>
00531 <font class="comment">/************************************************************************/</font>
00532
00533 CPLErr
00534 GDALComputeBandStats( GDALRasterBandH hSrcBand,
00535 <font class="keywordtype">int</font> nSampleStep,
00536 <font class="keywordtype">double</font> *pdfMean, <font class="keywordtype">double</font> *pdfStdDev,
00537 GDALProgressFunc pfnProgress,
00538 <font class="keywordtype">void</font> *pProgressData )<font class="keyword"></font>
00539 <font class="keyword"></font>
00540 <font class="keyword"></font>{
00541 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poSrcBand = (<a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *) hSrcBand;
00542 <font class="keywordtype">int</font> iLine, nWidth, nHeight;
00543 GDALDataType eType = poSrcBand-><a class="code" href="class_GDALRasterBand.html#a6">GetRasterDataType</a>();
00544 GDALDataType eWrkType;
00545 <font class="keywordtype">int</font> bComplex;
00546 <font class="keywordtype">float</font> *pafData;
00547 <font class="keywordtype">double</font> dfSum=0.0, dfSum2=0.0;
00548 <font class="keywordtype">int</font> nSamples = 0;
00549
00550 nWidth = poSrcBand-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>();
00551 nHeight = poSrcBand-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00552
00553 <font class="keywordflow">if</font>( nSampleStep >= nHeight )
00554 nSampleStep = 1;
00555
00556 bComplex = GDALDataTypeIsComplex(eType);
00557 <font class="keywordflow">if</font>( bComplex )
00558 {
00559 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>));
00560 eWrkType = GDT_CFloat32;
00561 }
00562 <font class="keywordflow">else</font>
00563 {
00564 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>));
00565 eWrkType = GDT_Float32;
00566 }
00567
00568 <font class="comment">/* -------------------------------------------------------------------- */</font>
00569 <font class="comment">/* Loop over all sample lines. */</font>
00570 <font class="comment">/* -------------------------------------------------------------------- */</font>
00571 <font class="keywordflow">for</font>( iLine = 0; iLine < nHeight; iLine += nSampleStep )
00572 {
00573 <font class="keywordtype">int</font> iPixel;
00574
00575 <font class="keywordflow">if</font>( !pfnProgress( iLine / (<font class="keywordtype">double</font>) nHeight,
00576 NULL, pProgressData ) )
00577 {
00578 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_UserInterrupt, <font class="stringliteral">"User terminated"</font> );
00579 CPLFree( pafData );
00580 <font class="keywordflow">return</font> CE_Failure;
00581 }
00582
00583 poSrcBand-><a class="code" href="class_GDALRasterBand.html#a9">RasterIO</a>( GF_Read, 0, iLine, nWidth, 1,
00584 pafData, nWidth, 1, eWrkType,
00585 0, 0 );
00586
00587 <font class="keywordflow">for</font>( iPixel = 0; iPixel < nWidth; iPixel++ )
00588 {
00589 <font class="keywordtype">float</font> fValue;
00590
00591 <font class="keywordflow">if</font>( bComplex )
00592 {
00593 <font class="comment">// Compute the magnitude of the complex value.</font>
00594
00595 fValue = sqrt(pafData[iPixel*2 ] * pafData[iPixel*2 ]
00596 + pafData[iPixel*2+1] * pafData[iPixel*2+1]);
00597 }
00598 <font class="keywordflow">else</font>
00599 {
00600 fValue = pafData[iPixel];
00601 }
00602
00603 dfSum += fValue;
00604 dfSum2 += fValue * fValue;
00605 }
00606
00607 nSamples += nWidth;
00608 }
00609
00610 <font class="keywordflow">if</font>( !pfnProgress( 1.0, NULL, pProgressData ) )
00611 {
00612 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_UserInterrupt, <font class="stringliteral">"User terminated"</font> );
00613 CPLFree( pafData );
00614 <font class="keywordflow">return</font> CE_Failure;
00615 }
00616
00617 <font class="comment">/* -------------------------------------------------------------------- */</font>
00618 <font class="comment">/* Produce the result values. */</font>
00619 <font class="comment">/* -------------------------------------------------------------------- */</font>
00620 <font class="keywordflow">if</font>( pdfMean != NULL )
00621 *pdfMean = dfSum / nSamples;
00622
00623 <font class="keywordflow">if</font>( pdfStdDev != NULL )
00624 {
00625 <font class="keywordtype">double</font> dfMean = dfSum / nSamples;
00626
00627 *pdfStdDev = sqrt((dfSum2 / nSamples) - (dfMean * dfMean));
00628 }
00629
00630 CPLFree( pafData );
00631
00632 <font class="keywordflow">return</font> CE_None;
00633 }
00634
00635 <font class="comment">/************************************************************************/</font>
00636 <font class="comment">/* GDALOverviewMagnitudeCorrection() */</font>
00637 <font class="comment">/* */</font>
00638 <font class="comment">/* Correct the mean and standard deviation of the overviews of */</font>
00639 <font class="comment">/* the given band to match the base layer approximately. */</font>
00640 <font class="comment">/************************************************************************/</font>
00641
00642 CPLErr
00643 GDALOverviewMagnitudeCorrection( GDALRasterBandH hBaseBand,
00644 <font class="keywordtype">int</font> nOverviewCount,
00645 GDALRasterBandH *pahOverviews,
00646 GDALProgressFunc pfnProgress,
00647 <font class="keywordtype">void</font> *pProgressData )<font class="keyword"></font>
00648 <font class="keyword"></font>
00649 <font class="keyword"></font>{
00650 CPLErr eErr;
00651 <font class="keywordtype">double</font> dfOrigMean, dfOrigStdDev;
00652
00653 <font class="comment">/* -------------------------------------------------------------------- */</font>
00654 <font class="comment">/* Compute mean/stddev for source raster. */</font>
00655 <font class="comment">/* -------------------------------------------------------------------- */</font>
00656 eErr = GDALComputeBandStats( hBaseBand, 2, &dfOrigMean, &dfOrigStdDev,
00657 pfnProgress, pProgressData );
00658
00659 <font class="keywordflow">if</font>( eErr != CE_None )
00660 <font class="keywordflow">return</font> eErr;
00661
00662 <font class="comment">/* -------------------------------------------------------------------- */</font>
00663 <font class="comment">/* Loop on overview bands. */</font>
00664 <font class="comment">/* -------------------------------------------------------------------- */</font>
00665 <font class="keywordtype">int</font> iOverview;
00666
00667 <font class="keywordflow">for</font>( iOverview = 0; iOverview < nOverviewCount; iOverview++ )
00668 {
00669 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poOverview = (<a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *)pahOverviews[iOverview];
00670 <font class="keywordtype">double</font> dfOverviewMean, dfOverviewStdDev;
00671 <font class="keywordtype">double</font> dfGain;
00672
00673 eErr = GDALComputeBandStats( pahOverviews[iOverview], 1,
00674 &dfOverviewMean, &dfOverviewStdDev,
00675 pfnProgress, pProgressData );
00676
00677 <font class="keywordflow">if</font>( eErr != CE_None )
00678 <font class="keywordflow">return</font> eErr;
00679
00680 <font class="keywordflow">if</font>( dfOrigStdDev < 0.0001 )
00681 dfGain = 1.0;
00682 <font class="keywordflow">else</font>
00683 dfGain = dfOrigStdDev / dfOverviewStdDev;
00684
00685 <font class="comment">/* -------------------------------------------------------------------- */</font>
00686 <font class="comment">/* Apply gain and offset. */</font>
00687 <font class="comment">/* -------------------------------------------------------------------- */</font>
00688 GDALDataType eWrkType, eType = poOverview-><a class="code" href="class_GDALRasterBand.html#a6">GetRasterDataType</a>();
00689 <font class="keywordtype">int</font> iLine, nWidth, nHeight, bComplex;
00690 <font class="keywordtype">float</font> *pafData;
00691
00692 nWidth = poOverview-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>();
00693 nHeight = poOverview-><a class="code" href="class_GDALRasterBand.html#a3">GetYSize</a>();
00694
00695 bComplex = GDALDataTypeIsComplex(eType);
00696 <font class="keywordflow">if</font>( bComplex )
00697 {
00698 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>));
00699 eWrkType = GDT_CFloat32;
00700 }
00701 <font class="keywordflow">else</font>
00702 {
00703 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>));
00704 eWrkType = GDT_Float32;
00705 }
00706
00707 <font class="keywordflow">for</font>( iLine = 0; iLine < nHeight; iLine++ )
00708 {
00709 <font class="keywordtype">int</font> iPixel;
00710
00711 <font class="keywordflow">if</font>( !pfnProgress( iLine / (<font class="keywordtype">double</font>) nHeight,
00712 NULL, pProgressData ) )
00713 {
00714 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_UserInterrupt, <font class="stringliteral">"User terminated"</font> );
00715 CPLFree( pafData );
00716 <font class="keywordflow">return</font> CE_Failure;
00717 }
00718
00719 poOverview-><a class="code" href="class_GDALRasterBand.html#a9">RasterIO</a>( GF_Read, 0, iLine, nWidth, 1,
00720 pafData, nWidth, 1, eWrkType,
00721 0, 0 );
00722
00723 <font class="keywordflow">for</font>( iPixel = 0; iPixel < nWidth; iPixel++ )
00724 {
00725 <font class="keywordflow">if</font>( bComplex )
00726 {
00727 pafData[iPixel*2] *= dfGain;
00728 pafData[iPixel*2+1] *= dfGain;
00729 }
00730 <font class="keywordflow">else</font>
00731 {
00732 pafData[iPixel] = (pafData[iPixel]-dfOverviewMean)*dfGain
00733 + dfOrigMean;
00734
00735 }
00736 }
00737
00738 poOverview-><a class="code" href="class_GDALRasterBand.html#a9">RasterIO</a>( GF_Write, 0, iLine, nWidth, 1,
00739 pafData, nWidth, 1, eWrkType,
00740 0, 0 );
00741 }
00742
00743 <font class="keywordflow">if</font>( !pfnProgress( 1.0, NULL, pProgressData ) )
00744 {
00745 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_UserInterrupt, <font class="stringliteral">"User terminated"</font> );
00746 CPLFree( pafData );
00747 <font class="keywordflow">return</font> CE_Failure;
00748 }
00749
00750 CPLFree( pafData );
00751 }
00752
00753 <font class="keywordflow">return</font> CE_None;
00754 }
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