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<hr><h1>gdaldefaultoverviews.cpp</h1><div class="fragment"><pre>00001 <font class="comment">/******************************************************************************</font>
00002 <font class="comment"> * $Id: gdaldefaultoverviews_cpp-source.html,v 1.10 2002/04/16 13:11:48 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: gdaldefaultoverviews_cpp-source.html,v $
00030 <font class="comment"> * Revision 1.10 2002/04/16 13:11:48 warmerda
00030 <font class="comment"> * updated
00030 <font class="comment"> *</font>
00031 <font class="comment"> * Revision 1.8 2001/10/18 14:35:22 warmerda</font>
00032 <font class="comment"> * avoid conflicts between parameters and member data</font>
00033 <font class="comment"> *</font>
00034 <font class="comment"> * Revision 1.7 2001/07/18 04:04:30 warmerda</font>
00035 <font class="comment"> * added CPL_CVSID</font>
00036 <font class="comment"> *</font>
00037 <font class="comment"> * Revision 1.6 2001/06/22 21:00:38 warmerda</font>
00038 <font class="comment"> * fixed several problems with regenerating existing overviews</font>
00039 <font class="comment"> *</font>
00040 <font class="comment"> * Revision 1.5 2001/06/22 13:52:03 warmerda</font>
00041 <font class="comment"> * fixed bug when refreshing overviews during build</font>
00042 <font class="comment"> *</font>
00043 <font class="comment"> * Revision 1.4 2001/06/20 16:08:54 warmerda</font>
00044 <font class="comment"> * GDALDefaultOverviews now remembers ovr filename, and allows explicit setting</font>
00045 <font class="comment"> *</font>
00046 <font class="comment"> * Revision 1.3 2000/06/19 18:48:49 warmerda</font>
00047 <font class="comment"> * fixed message</font>
00048 <font class="comment"> *</font>
00049 <font class="comment"> * Revision 1.2 2000/06/19 14:42:27 warmerda</font>
00050 <font class="comment"> * Don't close old overviews till after we have identified which already</font>
00051 <font class="comment"> * exist, otherwise multiple copies of overviews may be created.</font>
00052 <font class="comment"> *</font>
00053 <font class="comment"> * Revision 1.1 2000/04/21 21:54:05 warmerda</font>
00054 <font class="comment"> * New</font>
00055 <font class="comment"> *</font>
00056 <font class="comment"> */</font>
00057
00058 <font class="preprocessor">#include "gdal_priv.h"</font>
00059
00060 CPL_CVSID(<font class="stringliteral">"$Id: gdaldefaultoverviews_cpp-source.html,v 1.10 2002/04/16 13:11:48 warmerda Exp $"</font>);
00061
00062 <font class="comment">/************************************************************************/</font>
00063 <font class="comment">/* GDALDefaultOverviews() */</font>
00064 <font class="comment">/************************************************************************/</font>
00065
00066 GDALDefaultOverviews::GDALDefaultOverviews()<font class="keyword"></font>
00067 <font class="keyword"></font>
00068 <font class="keyword"></font>{
00069 poDS = NULL;
00070 poODS = NULL;
00071 pszOvrFilename = NULL;
00072 }
00073
00074 <font class="comment">/************************************************************************/</font>
00075 <font class="comment">/* ~GDALDefaultOverviews() */</font>
00076 <font class="comment">/************************************************************************/</font>
00077
00078 GDALDefaultOverviews::~GDALDefaultOverviews()<font class="keyword"></font>
00079 <font class="keyword"></font>
00080 <font class="keyword"></font>{
00081 <font class="keywordflow">if</font>( poODS != NULL )
00082 {
00083 poODS->FlushCache();
00084 <font class="keyword">delete</font> poODS;
00085 }
00086 CPLFree( pszOvrFilename );
00087 }
00088
00089 <font class="comment">/************************************************************************/</font>
00090 <font class="comment">/* Initialize() */</font>
00091 <font class="comment">/************************************************************************/</font>
00092
00093 <font class="keywordtype">void</font> GDALDefaultOverviews::Initialize( <a class="code" href="class_GDALDataset.html">GDALDataset</a> *poDSIn,
00094 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszBasename,
00095 <font class="keywordtype">int</font> bNameIsOVR )<font class="keyword"></font>
00096 <font class="keyword"></font>
00097 <font class="keyword"></font>{
00098 VSIStatBuf sStatBuf;
00099
00100 <font class="comment">/* -------------------------------------------------------------------- */</font>
00101 <font class="comment">/* If we were already initialized, destroy the old overview */</font>
00102 <font class="comment">/* file handle. */</font>
00103 <font class="comment">/* -------------------------------------------------------------------- */</font>
00104 <font class="keywordflow">if</font>( poODS != NULL )
00105 {
00106 <font class="keyword">delete</font> poODS;
00107 }
00108
00109 <font class="comment">/* -------------------------------------------------------------------- */</font>
00110 <font class="comment">/* Open overview dataset if it exists. */</font>
00111 <font class="comment">/* -------------------------------------------------------------------- */</font>
00112 poDS = poDSIn;
00113
00114 <font class="keywordflow">if</font>( pszBasename == NULL )
00115 pszBasename = poDS->GetDescription();
00116
00117 CPLFree( pszOvrFilename );
00118 pszOvrFilename = (<font class="keywordtype">char</font> *) <a class="code" href="cpl_conv_h.html#a3">CPLMalloc</a>(strlen(pszBasename)+5);
00119 <font class="keywordflow">if</font>( bNameIsOVR )
00120 strcpy( pszOvrFilename, pszBasename );
00121 <font class="keywordflow">else</font>
00122 sprintf( pszOvrFilename, <font class="stringliteral">"%s.ovr"</font>, pszBasename );
00123
00124 <font class="keywordflow">if</font>( VSIStat( pszOvrFilename, &sStatBuf ) == 0 )
00125 poODS = (<a class="code" href="class_GDALDataset.html">GDALDataset</a> *) <a class="code" href="gdal_h.html#a60">GDALOpen</a>( pszOvrFilename, poDS->GetAccess() );
00126 }
00127
00128 <font class="comment">/************************************************************************/</font>
00129 <font class="comment">/* GetOverviewCount() */</font>
00130 <font class="comment">/************************************************************************/</font>
00131
00132 <font class="keywordtype">int</font> GDALDefaultOverviews::GetOverviewCount( <font class="keywordtype">int</font> nBand )<font class="keyword"></font>
00133 <font class="keyword"></font>
00134 <font class="keyword"></font>{
00135 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> * poBand;
00136
00137 <font class="keywordflow">if</font>( poODS == NULL || nBand < 1 || nBand > poODS->GetRasterCount() )
00138 <font class="keywordflow">return</font> 0;
00139
00140 poBand = poODS->GetRasterBand( nBand );
00141 <font class="keywordflow">if</font>( poBand == NULL )
00142 <font class="keywordflow">return</font> 0;
00143 <font class="keywordflow">else</font>
00144 <font class="keywordflow">return</font> poBand-><a class="code" href="class_GDALRasterBand.html#a28">GetOverviewCount</a>() + 1;
00145 }
00146
00147 <font class="comment">/************************************************************************/</font>
00148 <font class="comment">/* GetOverview() */</font>
00149 <font class="comment">/************************************************************************/</font>
00150
00151 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *
00152 GDALDefaultOverviews::GetOverview( <font class="keywordtype">int</font> nBand, <font class="keywordtype">int</font> iOverview )<font class="keyword"></font>
00153 <font class="keyword"></font>
00154 <font class="keyword"></font>{
00155 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> * poBand;
00156
00157 <font class="keywordflow">if</font>( poODS == NULL || nBand < 1 || nBand > poODS->GetRasterCount() )
00158 <font class="keywordflow">return</font> NULL;
00159
00160 poBand = poODS->GetRasterBand( nBand );
00161 <font class="keywordflow">if</font>( poBand == NULL )
00162 <font class="keywordflow">return</font> NULL;
00163
00164 <font class="keywordflow">if</font>( iOverview == 0 )
00165 <font class="keywordflow">return</font> poBand;
00166 <font class="keywordflow">else</font> <font class="keywordflow">if</font>( iOverview-1 >= poBand-><a class="code" href="class_GDALRasterBand.html#a28">GetOverviewCount</a>() )
00167 <font class="keywordflow">return</font> NULL;
00168 <font class="keywordflow">else</font>
00169 <font class="keywordflow">return</font> poBand-><a class="code" href="class_GDALRasterBand.html#a29">GetOverview</a>( iOverview-1 );
00170 }
00171
00172 <font class="comment">/************************************************************************/</font>
00173 <font class="comment">/* GDALOvLevelAdjust() */</font>
00174 <font class="comment">/* */</font>
00175 <font class="comment">/* Some overview levels cannot be achieved closely enough to be */</font>
00176 <font class="comment">/* recognised as the desired overview level. This function */</font>
00177 <font class="comment">/* will adjust an overview level to one that is achievable on */</font>
00178 <font class="comment">/* the given raster size. */</font>
00179 <font class="comment">/* */</font>
00180 <font class="comment">/* For instance a 1200x1200 image on which a 256 level overview */</font>
00181 <font class="comment">/* is request will end up generating a 5x5 overview. However, */</font>
00182 <font class="comment">/* this will appear to the system be a level 240 overview. */</font>
00183 <font class="comment">/* This function will adjust 256 to 240 based on knowledge of */</font>
00184 <font class="comment">/* the image size. */</font>
00185 <font class="comment">/************************************************************************/</font>
00186
00187 <font class="keyword">static</font> <font class="keywordtype">int</font> GDALOvLevelAdjust( <font class="keywordtype">int</font> nOvLevel, <font class="keywordtype">int</font> nXSize )<font class="keyword"></font>
00188 <font class="keyword"></font>
00189 <font class="keyword"></font>{
00190 <font class="keywordtype">int</font> nOXSize = (nXSize + nOvLevel - 1) / nOvLevel;
00191
00192 <font class="keywordflow">return</font> (<font class="keywordtype">int</font>) (0.5 + nXSize / (<font class="keywordtype">double</font>) nOXSize);
00193 }
00194
00195 <font class="comment">/************************************************************************/</font>
00196 <font class="comment">/* GDALDefaultBuildOverviews() */</font>
00197 <font class="comment">/************************************************************************/</font>
00198
00199 CPLErr
00200 GDALDefaultOverviews::BuildOverviews(
00201 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszBasename,
00202 <font class="keyword">const</font> <font class="keywordtype">char</font> * pszResampling,
00203 <font class="keywordtype">int</font> nOverviews, <font class="keywordtype">int</font> * panOverviewList,
00204 <font class="keywordtype">int</font> nBands, <font class="keywordtype">int</font> * panBandList,
00205 GDALProgressFunc pfnProgress, <font class="keywordtype">void</font> * pProgressData)<font class="keyword"></font>
00206 <font class="keyword"></font>
00207 <font class="keyword"></font>{
00208 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> **pahBands;
00209 CPLErr eErr;
00210 <font class="keywordtype">int</font> i;
00211
00212 <font class="comment">/* -------------------------------------------------------------------- */</font>
00213 <font class="comment">/* Our TIFF overview support currently only works safely if all */</font>
00214 <font class="comment">/* bands are handled at the same time. */</font>
00215 <font class="comment">/* -------------------------------------------------------------------- */</font>
00216 <font class="keywordflow">if</font>( nBands != poDS->GetRasterCount() )
00217 {
00218 <a class="code" href="cpl_error_h.html#a17">CPLError</a>( CE_Failure, CPLE_NotSupported,
00219 <font class="stringliteral">"Generation of overviews in external TIFF currently only"</font>
00220 <font class="stringliteral">" supported when operating on all bands.\n"</font>
00221 <font class="stringliteral">"Operation failed.\n"</font> );
00222 <font class="keywordflow">return</font> CE_Failure;
00223 }
00224
00225 <font class="comment">/* -------------------------------------------------------------------- */</font>
00226 <font class="comment">/* If a basename is provided, use it to override the internal */</font>
00227 <font class="comment">/* overview filename. */</font>
00228 <font class="comment">/* -------------------------------------------------------------------- */</font>
00229 <font class="keywordflow">if</font>( pszBasename == NULL && pszOvrFilename == NULL )
00230 pszBasename = poDS->GetDescription();
00231
00232 <font class="keywordflow">if</font>( pszBasename != NULL )
00233 {
00234 CPLFree( pszOvrFilename );
00235 pszOvrFilename = (<font class="keywordtype">char</font> *) <a class="code" href="cpl_conv_h.html#a3">CPLMalloc</a>(strlen(pszBasename)+5);
00236 sprintf( pszOvrFilename, <font class="stringliteral">"%s.ovr"</font>, pszBasename );
00237 }
00238
00239 <font class="comment">/* -------------------------------------------------------------------- */</font>
00240 <font class="comment">/* Establish which of the overview levels we already have, and */</font>
00241 <font class="comment">/* which are new. We assume that band 1 of the file is */</font>
00242 <font class="comment">/* representative. */</font>
00243 <font class="comment">/* -------------------------------------------------------------------- */</font>
00244 <font class="keywordtype">int</font> nNewOverviews, *panNewOverviewList = NULL;
00245 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *poBand = poDS->GetRasterBand( 1 );
00246
00247 nNewOverviews = 0;
00248 panNewOverviewList = (<font class="keywordtype">int</font> *) <a class="code" href="cpl_conv_h.html#a4">CPLCalloc</a>(<font class="keyword">sizeof</font>(<font class="keywordtype">int</font>),nOverviews);
00249 <font class="keywordflow">for</font>( i = 0; i < nOverviews && poBand != NULL; i++ )
00250 {
00251 <font class="keywordtype">int</font> j;
00252
00253 <font class="keywordflow">for</font>( j = 0; j < poBand->GetOverviewCount(); j++ )
00254 {
00255 <font class="keywordtype">int</font> nOvFactor;
00256 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> * poOverview = poBand-><a class="code" href="class_GDALRasterBand.html#a29">GetOverview</a>( j );
00257
00258 nOvFactor = (<font class="keywordtype">int</font>)
00259 (0.5 + poBand-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>() / (<font class="keywordtype">double</font>) poOverview-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>());
00260
00261 <font class="keywordflow">if</font>( nOvFactor == panOverviewList[i]
00262 || nOvFactor == GDALOvLevelAdjust( panOverviewList[i],
00263 poBand-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>() ) )
00264 panOverviewList[i] *= -1;
00265 }
00266
00267 <font class="keywordflow">if</font>( panOverviewList[i] > 0 )
00268 panNewOverviewList[nNewOverviews++] = panOverviewList[i];
00269 }
00270
00271 <font class="comment">/* -------------------------------------------------------------------- */</font>
00272 <font class="comment">/* If we have an existing overview file open, close it now. */</font>
00273 <font class="comment">/* -------------------------------------------------------------------- */</font>
00274 <font class="keywordflow">if</font>( poODS != NULL )
00275 {
00276 <font class="keyword">delete</font> poODS;
00277 poODS = NULL;
00278 }
00279
00280 <font class="comment">/* -------------------------------------------------------------------- */</font>
00281 <font class="comment">/* Build band list. */</font>
00282 <font class="comment">/* -------------------------------------------------------------------- */</font>
00283 pahBands = (<a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> **) <a class="code" href="cpl_conv_h.html#a4">CPLCalloc</a>(<font class="keyword">sizeof</font>(<a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> *),nBands);
00284 <font class="keywordflow">for</font>( i = 0; i < nBands; i++ )
00285 pahBands[i] = poDS->GetRasterBand( panBandList[i] );
00286
00287 <font class="comment">/* -------------------------------------------------------------------- */</font>
00288 <font class="comment">/* Build new overviews. */</font>
00289 <font class="comment">/* -------------------------------------------------------------------- */</font>
00290
00291 eErr = GTIFFBuildOverviews( pszOvrFilename, nBands, pahBands,
00292 nNewOverviews, panNewOverviewList,
00293 pszResampling, pfnProgress, pProgressData );
00294
00295 <font class="comment">/* -------------------------------------------------------------------- */</font>
00296 <font class="comment">/* Refresh old overviews that were listed. */</font>
00297 <font class="comment">/* -------------------------------------------------------------------- */</font>
00298 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> **papoOverviewBands;
00299
00300 <font class="keywordflow">if</font>( eErr == CE_None )
00301 {
00302 poODS = (<a class="code" href="class_GDALDataset.html">GDALDataset</a> *) <a class="code" href="gdal_h.html#a60">GDALOpen</a>( pszOvrFilename, GA_Update );
00303 <font class="keywordflow">if</font>( poODS == NULL )
00304 eErr = CE_Failure;
00305 }
00306
00307 papoOverviewBands = (<a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> **)
00308 <a class="code" href="cpl_conv_h.html#a4">CPLCalloc</a>(<font class="keyword">sizeof</font>(<font class="keywordtype">void</font>*),nOverviews);
00309
00310 <font class="keywordflow">for</font>( <font class="keywordtype">int</font> iBand = 0; iBand < nBands && eErr == CE_None; iBand++ )
00311 {
00312 poBand = poDS->GetRasterBand( panBandList[iBand] );
00313
00314 nNewOverviews = 0;
00315 <font class="keywordflow">for</font>( i = 0; i < nOverviews && poBand != NULL; i++ )
00316 {
00317 <font class="keywordtype">int</font> j;
00318
00319 <font class="keywordflow">for</font>( j = 0; j < poBand->GetOverviewCount(); j++ )
00320 {
00321 <font class="keywordtype">int</font> nOvFactor;
00322 <a class="code" href="class_GDALRasterBand.html">GDALRasterBand</a> * poOverview = poBand-><a class="code" href="class_GDALRasterBand.html#a29">GetOverview</a>( j );
00323
00324 nOvFactor = (<font class="keywordtype">int</font>)
00325 (0.5 + poBand-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>() / (<font class="keywordtype">double</font>) poOverview-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>());
00326
00327 <font class="keywordflow">if</font>( nOvFactor == - panOverviewList[i]
00328 || nOvFactor == GDALOvLevelAdjust( -panOverviewList[i],
00329 poBand-><a class="code" href="class_GDALRasterBand.html#a2">GetXSize</a>() ) )
00330 {
00331 panOverviewList[i] *= -1;
00332 papoOverviewBands[nNewOverviews++] = poOverview;
00333 }
00334 }
00335 }
00336
00337 <font class="keywordflow">if</font>( nNewOverviews > 0 )
00338 {
00339 eErr = GDALRegenerateOverviews( poBand,
00340 nNewOverviews, papoOverviewBands,
00341 pszResampling,
00342 GDALDummyProgress, NULL );
00343 }
00344 }
00345
00346 <font class="comment">/* -------------------------------------------------------------------- */</font>
00347 <font class="comment">/* Cleanup */</font>
00348 <font class="comment">/* -------------------------------------------------------------------- */</font>
00349 CPLFree( papoOverviewBands );
00350 CPLFree( panNewOverviewList );
00351 CPLFree( pahBands );
00352
00353 <font class="keywordflow">return</font> eErr;
00354 }
00355
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