ëÁË ÔÏÌØËÏ ÄÒÁÊ×ÅÒÙ ÚÁÒÅÇÉÓÔÒÉÒÏ×ÁÎÙ, ÐÒÉÌÏÖÅÎÉÅ ÄÏÌÖÎÏ ×ÙÚ×ÁÔØ ÆÕÎËÃÉÀ GDALOpen() ÄÌÑ ÏÔËÒÙÔÉÑ ÎÁÂÏÒÁ ÄÁÎÎÙÈ. ÷ ËÁÞÅÓÔ×Å ÐÁÒÁÍÅÔÒÏ× ÆÕÎËÃÉÑ ÐÒÉÎÉÍÁÅÔ ÎÁÚ×ÁÎÉÅ ÎÁÂÏÒÁ ÄÁÎÎÙÈ É ÒÅÖÉÍ ÄÏÓÔÕÐÁ (GA_ReadOnly ÉÌÉ GA_Update).
îÁ ÑÚÙËÅ C++:
#include "gdal_priv.h" int main() { GDALDataset *poDataset; GDALAllRegister(); poDataset = (GDALDataset *) GDALOpen( pszFilename, GA_ReadOnly ); if( poDataset == NULL ) { ...; }
îÁ ÑÚÙËÅ C:
#include "gdal.h" int main() { GDALDatasetH hDataset; GDALAllRegister(); hDataset = GDALOpen( pszFilename, GA_ReadOnly ); if( hDataset == NULL ) { ...; }
îÁ ÑÚÙËÅ Python:
import gdal from gdalconst import * dataset = gdal.Open( filename, GA_ReadOnly ) if dataset is None: ...
åÓÌÉ GDALOpen() ×ÏÚ×ÒÁÝÁÅÔ NULL, ÜÔÏ ÏÚÎÁÞÁÅÔ, ÞÔÏ ÏÐÅÒÁÃÉÑ ÎÅ ÕÄÁÌÁÓØ É ÞÔÏ ÓÏÏÂÝÅÎÉÑ Ï ÏÛÉÂËÅ ÂÙÌÉ ÐÏÓÌÁÎÙ Ó ÐÏÍÏÝØÀ ÆÕÎËÃÉÉ CPLError(). åÓÌÉ ×Ù ÈÏÔÉÔÅ ÕÐÒÁ×ÌÑÔØ ÐÒÏÃÅÓÓÏÍ ×ÙÄÁÞÉ ÐÏÌØÚÏ×ÁÔÅÌÀ ÓÏÏÂÝÅÎÉÊ Ï ÏÛÉÂËÁÈ, ÔÏ ÏÂÒÁÔÉÔÅÓØ Ë ÄÏËÕÍÅÎÔÁÃÉÉ ÎÁ ÆÕÎËÃÉÀ CPLError(). ÷ÏÏÂÝÅ ÇÏ×ÏÒÑ, CPLError() ÐÒÉÍÅÎÑÅÔÓÑ ×Ï ×ÓÅÈ ËÏÍÐÏÎÅÎÔÁÈ GDAL ÄÌÑ ×ÙÄÁÞÉ ÓÏÏÂÝÅÎÉÊ Ï ÏÛÉÂËÁÈ. úÁÍÅÔÉÍ ÔÁËÖÅ, ÞÔÏ pszFilename ÎÅ ÄÏÌÖÎÁ ÏÂÑÚÁÔÅÌØÎÏ ÂÙÔØ ÉÍÅÎÅÍ ÆÁÊÌÁ ÎÁ ÆÉÚÉÞÅÓËÏÍ ÎÏÓÉÔÅÌÅ (ÈÏÔÑ ÏÂÙÞÎÏ ÜÔÏ ÔÁË). éÎÔÅÒÐÒÅÔÁÃÉÑ ÜÔÏÇÏ ÐÁÒÁÍÅÔÒÁ ÚÁ×ÉÓÉÔ ÏÔ ÄÒÁÊ×ÅÒÁ, ÜÔÏ ÍÏÖÅÔ ÂÙÔØ URL ÉÌÉ ÉÍÑ ÆÁÊÌÁ Ó ÄÏÐÏÌÎÉÔÅÌØÎÙÍÉ ÐÁÒÁÍÅÔÒÁÍÉ, ÕÐÒÁ×ÌÑÀÝÉÍÉ ÐÒÏÃÅÓÓÏÍ ÞÔÅÎÉÑ, ÌÉÂÏ ÞÅÍ-ÔÏ ÉÎÙÍ. ðÏÖÁÌÕÊÓÔÁ, ÎÅ ÏÇÒÁÎÉÞÉ×ÁÊÔÅ ÄÉÁÌÏÇÉ ×ÙÂÏÒÁ ÎÁÂÏÒÁ ÄÁÎÎÙÈ ÄÌÑ ÏÔËÒÙÔÉÑ ÔÏÌØËÏ ÌÉÛØ ÆÁÊÌÁÍÉ ÎÁ ÆÉÚÉÞÅÓËÉÈ ÎÏÓÉÔÅÌÑÈ.
adfGeoTransform[0] /* ËÏÏÒÄÉÎÁÔÁ x ×ÅÒÈÎÅÇÏ ÌÅ×ÏÇÏ ÕÇÌÁ */ adfGeoTransform[1] /* ÛÉÒÉÎÁ ÐÉËÓÅÌÁ */ adfGeoTransform[2] /* ÐÏ×ÏÒÏÔ, 0, ÅÓÌÉ ÉÚÏÂÒÁÖÅÎÉÅ ÏÒÉÅÎÔÉÒÏ×ÁÎÏ ÎÁ ÓÅ×ÅÒ */ adfGeoTransform[3] /* ËÏÏÒÄÉÎÁÔÁ y ×ÅÒÈÎÅÇÏ ÌÅ×ÏÇÏ ÕÇÌÁ */ adfGeoTransform[4] /* ÐÏ×ÏÒÏÔ, 0, ÅÓÌÉ ÉÚÏÂÒÁÖÅÎÉÅ ÏÒÉÅÎÔÉÒÏ×ÁÎÏ ÎÁ ÓÅ×ÅÒ */ adfGeoTransform[5] /* ×ÙÓÏÔÁ ÐÉËÓÅÌÁ */
åÓÌÉ ÍÙ ÈÏÔÉÍ ×Ù×ÅÓÔÉ ÎÅËÏÔÏÒÕÀ ÏÂÝÕÀ ÉÎÆÏÒÍÁÃÉÀ Ï ÎÁÂÏÒÅ ÄÁÎÎÙÈ, ÔÏ ÍÏÖÎÏ ÓÄÅÌÁÔØ ÓÌÅÄÕÀÝÅÅ:
îÁ ÑÚÙËÅ C++:
double adfGeoTransform[6]; printf( "äÒÁÊ×ÅÒ: %s/%s\n", poDataset->GetDriver()->GetDescription(), poDataset->GetDriver()->GetMetadataItem( GDAL_DMD_LONGNAME ) ); printf( "òÁÚÍÅÒ %dx%dx%d\n", poDataset->GetRasterXSize(), poDataset->GetRasterYSize(), poDataset->GetRasterCount() ); if( poDataset->GetProjectionRef() != NULL ) printf( "ðÒÏÅËÃÉÑ \"%s\"\n", poDataset->GetProjectionRef() ); if( poDataset->GetGeoTransform( adfGeoTransform ) == CE_None ) { printf( "îÁÞÁÌÏ ËÏÏÒÄÉÎÁÔ (%.6f,%.6f)\n", adfGeoTransform[0], adfGeoTransform[3] ); printf( "òÁÚÍÅÒ ÐÉËÓÅÌÁ (%.6f,%.6f)\n", adfGeoTransform[1], adfGeoTransform[5] ); }
îÁ ÑÚÙËÅ C:
GDALDriverH hDriver; double adfGeoTransform[6]; hDriver = GDALGetDatasetDriver( hDataset ); printf( "äÒÁÊ×ÅÒ: %s/%s\n", GDALGetDriverShortName( hDriver ), GDALGetDriverLongName( hDriver ) ); printf( "òÁÚÍÅÒ %dx%dx%d\n", GDALGetRasterXSize( hDataset ), GDALGetRasterYSize( hDataset ), GDALGetRasterCount( hDataset ) ); if( GDALGetProjectionRef( hDataset ) != NULL ) printf( "ðÒÏÅËÃÉÑ \"%s\"\n", GDALGetProjectionRef( hDataset ) ); if( GDALGetGeoTransform( hDataset, adfGeoTransform ) == CE_None ) { printf( "îÁÞÁÌÏ ËÏÏÒÄÉÎÁÔ (%.6f,%.6f)\n", adfGeoTransform[0], adfGeoTransform[3] ); printf( "òÁÚÍÅÒ ÐÉËÓÅÌÁ (%.6f,%.6f)\n", adfGeoTransform[1], adfGeoTransform[5] ); }
îÁ ÑÚÙËÅ Python:
print 'äÒÁÊ×ÅÒ: ', dataset.GetDriver().ShortName,'/', \ dataset.GetDriver().LongName print 'òÁÚÍÅÒ ',dataset.RasterXSize,'x',dataset.RasterYSize, \ 'x',dataset.RasterCount print 'ðÒÏÅËÃÉÑ ',dataset.GetProjection() geotransform = dataset.GetGeoTransform() if not geotransform is None: print 'îÁÞÁÌÏ ËÏÏÒÄÉÎÁÔ (',geotransform[0], ',',geotransform[3],')' print 'òÁÚÍÅÒ ÐÉËÓÅÌÁ = (',geotransform[1], ',',geotransform[5],')'
îÁ ÑÚÙËÅ C++:
GDALRasterBand *poBand; int nBlockXSize, nBlockYSize; int bGotMin, bGotMax; double adfMinMax[2]; poBand = poDataset->GetRasterBand( 1 ); poBand->GetBlockSize( &nBlockXSize, &nBlockYSize ); printf( "òÁÚÍÅÒ ÂÌÏËÁ %dx%d, ÔÉÐ ÄÁÎÎÙÈ %s, ColorInterp=%s\n", nBlockXSize, nBlockYSize, GDALGetDataTypeName(poBand->GetRasterDataType()), GDALGetColorInterpretationName( poBand->GetColorInterpretation()) ); adfMinMax[0] = poBand->GetMinimum( &bGotMin ); adfMinMax[1] = poBand->GetMaximum( &bGotMax ); if( ! (bGotMin && bGotMax) ) GDALComputeRasterMinMax((GDALRasterBandH)poBand, TRUE, adfMinMax); printf( "Min=%.3fd, Max=%.3f\n", adfMinMax[0], adfMinMax[1] ); if( poBand->GetOverviewCount() > 0 ) printf( "ëÁÎÁÌ ÓÏÄÅÒÖÉÔ %d ÏÂÚÏÒÎÙÈ ÉÚÏÂÒÁÖÅÎÉÊ.\n", poBand->GetOverviewCount() ); if( poBand->GetColorTable() != NULL ) printf( "ëÁÎÁÌ ÓÏÄÅÒÖÉÔ ÔÁÂÌÉÃÕ Ã×ÅÔÏ× Ó %d ÚÁÐÉÓÑÍÉ.\n", poBand->GetColorTable()->GetColorEntryCount() );
In C:
GDALRasterBandH hBand; int nBlockXSize, nBlockYSize; int bGotMin, bGotMax; double adfMinMax[2]; hBand = GDALGetRasterBand( hDataset, 1 ); GDALGetBlockSize( hBand, &nBlockXSize, &nBlockYSize ); printf( "òÁÚÍÅÒ ÂÌÏËÁ %dx%d, ÔÉÐ ÄÁÎÎÙÈ %s, ColorInterp=%s\n", nBlockXSize, nBlockYSize, GDALGetDataTypeName(GDALGetRasterDataType(hBand)), GDALGetColorInterpretationName( GDALGetRasterColorInterpretation(hBand)) ); adfMinMax[0] = GDALGetRasterMinimum( hBand, &bGotMin ); adfMinMax[1] = GDALGetRasterMaximum( hBand, &bGotMax ); if( ! (bGotMin && bGotMax) ) GDALComputeRasterMinMax( hBand, TRUE, adfMinMax ); printf( "Min=%.3fd, Max=%.3f\n", adfMinMax[0], adfMinMax[1] ); if( GDALGetOverviewCount(hBand) > 0 ) printf( "ëÁÎÁÌ ÓÏÄÅÒÖÉÔ %d ÏÂÚÏÒÎÙÈ ÉÚÏÂÒÁÖÅÎÉÊ.\n", GDALGetOverviewCount(hBand)); if( GDALGetRasterColorTable( hBand ) != NULL ) printf( "ëÁÎÁÌ ÓÏÄÅÒÖÉÔ ÔÁÂÌÉÃÕ Ã×ÅÔÏ× Ó %d ÚÁÐÉÓÑÍÉ.\n", GDALGetColorEntryCount( GDALGetRasterColorTable( hBand ) ) );
îÁ ÑÚÙËÅ Python:
band = dataset.GetRasterBand(1) print 'ôÉÐ ÄÁÎÎÙÈ',gdal.GetDataTypeName(band.DataType) min = band.GetMinimum() max = band.GetMaximum() if min is not None and max is not None: (min,max) = ComputeRasterMinMax(1) print 'Min=%.3f, Max=%.3f' % (min,max) if band.GetOverviewCount() > 0: print 'ëÁÎÁÌ ÓÏÄÅÒÖÉÔ ', band.GetOverviewCount(), \ ' ÏÂÚÏÒÎÙÈ ÉÚÏÂÒÁÖÅÎÉÊ.' if not band.GetRasterColorTable() is None: print 'ëÁÎÁÌ ÓÏÄÅÒÖÉÔ ÔÁÂÌÉÃÕ Ã×ÅÔÏ× Ó ', \ band.GetRasterColorTable().GetCount(), ' ÚÁÐÉÓÑÍÉ.'
îÁ ÑÚÙËÅ C++:
float *pafScanline; int nXSize = poBand->GetXSize(); pafScanline = (float *) CPLMalloc(sizeof(float)*nXSize); poBand->RasterIO( GF_Read, 0, 0, nXSize, 1, pafScanline, nXSize, 1, GDT_Float32, 0, 0 );
îÁ ÑÚÙËÅ C:
float *pafScanline; int nXSize = GDALGetRasterBandXSize( hBand ); pafScanline = (float *) CPLMalloc(sizeof(float)*nXSize); GDALRasterIO( hBand, GF_Read, 0, 0, nXSize, 1, pafScanline, nXSize, 1, GDT_Float32, 0, 0 );
îÁ ÑÚÙËÅ Python:
scanline = band.ReadRaster( 0, 0, band.XSize, 1, \ band.XSize, 1, GDT_Float32 )
úÄÅÓØ ×ÏÚ×ÒÁÝÁÅÍÁÑ ÓÔÒÏËÁ ÉÍÅÅÔ ÔÉÐ string, É ÓÏÄÅÒÖÉÔ xsize*4 ÂÁÊÔ ×ÅÝÅÓÔ×ÅÎÎÙÈ ÄÁÎÎÙÈ. üÔÁ ÓÔÒÏËÁ ÍÏÖÅÔ ÂÙÔØ ÐÒÅÏÂÒÁÚÏ×ÁÎÁ × ÂÁÚÏ×ÙÅ ÔÉÐÙ ÑÚÙËÁ Python Ó ÐÏÍÏÝØÀ ÍÏÄÕÌÑ struct ÉÚ ÓÔÁÎÄÁÒÔÎÏÊ ÂÉÂÌÉÏÔÅËÉ:
import struct tuple_of_floats = struct.unpack('f' * b2.XSize, scanline)
÷ÙÚÏ× ÆÕÎËÃÉÉ The RasterIO ÐÒÏÉÚ×ÏÄÉÔÓÑ ÓÏ ÓÌÅÄÕÀÝÉÍÉ ÁÒÇÕÍÅÎÔÁÍÉ:
CPLErr GDALRasterBand::RasterIO( GDALRWFlag eRWFlag, int nXOff, int nYOff, int nXSize, int nYSize, void * pData, int nBufXSize, int nBufYSize, GDALDataType eBufType, int nPixelSpace, int nLineSpace )
úÁÍÅÔÉÍ, ÞÔÏ ÏÄÉÎ É ÔÏÔ ÖÅ ×ÙÚÏ× RasterIO() ÐÒÉÍÅÎÑÅÔÓÑ ËÁË ÄÌÑ ÞÔÅÎÉÑ, ÔÁË É ÄÌÑ ÚÁÐÉÓÉ, × ÚÁ×ÉÓÉÍÏÓÔÉ ÏÔ ÚÎÁÞÅÎÉÑ ÆÌÁÇÁ eRWFlag (GF_Read ÉÌÉ GF_Write). áÒÇÕÍÅÎÔÙ nXOff, nYOff, nXSize, nYSize ÏÐÉÓÙ×ÁÀÔ ÏËÎÏ ÒÁÓÔÒÁ ÄÌÑ ÞÔÅÎÉÑ (ÉÌÉ ÚÁÐÉÓÉ). üÔÏ ÏËÎÏ ÎÅÏÂÑÚÁÔÅÌØÎÏ ÄÏÌÖÎÏ ÓÏ×ÐÁÄÁÔØ Ó ÇÒÁÎÉÃÁÍÉ ÓÍÅÖÎÙÈ ÂÌÏËÏ×, ÏÄÎÁËÏ ÓÞÉÔÙ×ÁÎÉÅ ÍÏÖÅÔ ÂÙÔØ ÂÏÌÅÅ ÜÆÆÅËÔÉ×ÎÙÍ, ÅÓÌÉ ÇÒÁÎÉÃÙ ÓÏ×ÐÁÄÁÀÔ.
pData --- ÜÔÏ ÕËÁÚÁÔÅÌØ ÎÁ ÂÕÆÅÒ × ÐÁÍÑÔÉ, ËÕÄÁ ÄÏÌÖÎÙ ÂÙÔØ ÐÒÏÞÉÔÁÎÙ (ÉÌÉ ÏÔËÕÄÁ ÚÁÐÉÓÁÎÙ) ÄÁÎÎÙÅ. æÁËÔÉÞÅÓËÉÊ ÔÉÐ ÜÔÏÇÏ ÂÕÆÅÒÁ ÄÏÌÖÅÎ ÓÏ×ÐÁÄÁÔØ Ó ÔÉÐÏÍ, ÐÅÒÅÄÁ×ÁÅÍÙÍ × ÐÁÒÁÍÅÔÒÅ eBufType, ÎÁÐÒÉÍÅÒ, GDT_Float32 ÉÌÉ GDT_Byte. æÕÎËÃÉÑ RasterIO() ×ÏÚØÍ£Ô ÎÁ ÓÅÂÑ ÐÒÅÏÂÒÁÚÏ×ÁÎÉÅ ÍÅÖÄÕ ÔÉÐÏÍ ÄÁÎÎÙÈ ÂÕÆÅÒÁ É ÔÉÐÏÍ ÄÁÎÎÙÈ ËÁÎÁÌÁ. ïÂÒÁÔÉÔÅ ×ÎÉÍÁÎÉÅ, ÞÔÏ ÐÒÉ ÐÒÅÏÂÒÁÚÏ×ÁÎÉÉ ×ÅÝÅÓÔ×ÅÎÎÙÈ ÄÁÎÎÙÈ × ÃÅÌÙÅ RasterIO() ÏËÒÕÇÌÑÅÔ × ÍÅÎØÛÕÀ ÓÔÏÒÏÎÕ, Á ÅÓÌÉ ÚÎÁÞÅÎÉÅ ×ÙÈÏÄÉÔ ÚÁ ÒÁÍËÉ ÄÏÐÕÓÔÉÍÏÇÏ ÄÉÁÐÁÚÏÎÁ, ÏÎÏ ÐÒÅÏÂÒÁÚÕÅÔÓÑ × ÂÌÉÖÁÊÛÅÅ ÄÏÐÕÓÔÉÍÏÅ ÚÎÁÞÅÎÉÅ. üÔÏ, ÎÁÐÒÉÍÅÒ, ÏÚÎÁÞÁÅÔ, ÞÔÏ ÐÒÉ ÞÔÅÎÉÉ 16-ÂÉÔÎÙÈ ÄÁÎÎÙÈ × ÂÕÆÅÒ ÔÉÐÁ GDT_Byte ×ÓÅ ÚÎÁÞÅÎÉÑ, ÐÒÅ×ÙÛÁÀÝÉÅ 255 ÂÕÄÕÔ ÏÔÏÂÒÁÖÅÎÙ × ÚÎÁÞÅÎÉÅ 255, ÍÁÓÛÔÁÂÉÒÏ×ÁÎÉÑ ÄÁÎÎÙÈ ÎÅ ÐÒÏÉÚÏÊÄ£Ô!
ðÁÒÁÍÅÔÒÙ nBufXSize É nBufYSize ÚÁÄÁÀÔ ÒÁÚÍÅÒ ÂÕÆÅÒÁ. ðÒÉ ÚÁÇÒÕÚËÅ ÄÁÎÎÙÈ × ÐÏÌÎÏÍ ÒÁÚÒÅÛÅÎÉÉ ÏÎ ÂÕÄÅÔ ÓÏ×ÐÁÄÁÔØ Ó ÒÁÚÍÅÒÏÍ ÏËÎÁ. ïÄÎÁËÏ ÄÌÑ ÚÁÇÒÕÚËÉ ÕÍÅÎØÛÅÎÎÏÇÏ ÏÂÚÏÒÎÏÇÏ ÉÚÏÂÒÁÖÅÎÉÑ ÒÁÚÍÅÒ ÂÕÆÅÒÁ ÍÏÖÎÏ ÕÓÔÁÎÏ×ÉÔØ ÍÅÎØÛÉÍ, ÞÅÍ ÒÁÚÍÅÒ ÏËÎÁ. ÷ ÜÔÏÍ ÓÌÕÞÁÅ RasterIO() ÂÕÄÅÔ ÉÓÐÏÌØÚÏ×ÁÔØ ÐÏÄÈÏÄÑÝÉÅ ÏÂÚÏÒÎÙÅ ÉÚÏÂÒÁÖÅÎÉÑ (ÐÉÒÁÍÉÄÕ) ÄÌÑ ÂÏÌÅÅ ÜÆÆÅËÔÉ×ÎÏÇÏ ××ÏÄÁ/×Ù×ÏÄÁ.
ðÁÒÁÍÅÔÒÙ nPixelSpace É nLineSpace ÏÂÙÞÎÏ ÒÁ×ÎÙ ÎÕÌÀ, ÞÔÏ ÐÒÉ×ÏÄÉÔ Ë ÉÓÐÏÌØÚÏ×ÁÎÉÀ ÚÎÁÞÅÎÉÊ ÐÏ ÕÍÏÌÞÁÎÉÀ. ïÄÎÁËÏ ÏÎÉ ÍÏÇÕÔ ÂÙÔØ ÉÓÐÏÌØÚÏ×ÁÎÙ ÄÌÑ ÕÐÒÁ×ÌÅÎÉÑ ÄÏÓÔÕÐÏÍ Ë ÂÕÆÅÒÕ ÄÁÎÎÙÈ, ÄÁ×ÁÑ ×ÏÚÍÏÖÎÏÓÔØ ÞÉÔÁÔØ × ÂÕÆÅÒ, ËÏÔÏÒÙÊ ÕÖÅ ÓÏÄÅÒÖÉÔ ÄÒÕÇÉÅ ÄÁÎÎÙÅ, ÞÅÒÅÄÕÑ ÐÉËÓÅÌÉ ÉÌÉ ÓÔÒÏËÉ.
óÐÏÓÏ CreateCopy ÐÒÅÄÐÏÌÁÇÁÅÔ ×ÙÚÏ× ÆÕÎËÃÉÉ CreateCopy() Ó ÕËÁÚÁÎÉÅÍ ÔÒÅÂÕÅÍÏÇÏ ÄÒÁÊ×ÅÒÁ ×ÙÈÏÄÎÏÇÏ ÆÏÒÍÁÔÁ É ÐÅÒÅÄÁÞÅÊ ÉÓÈÏÄÎÏÇÏ ÎÁÂÏÒÁ ÄÁÎÎÙÈ, ËÏÐÉÑ ËÏÔÏÒÏÇÏ ÄÏÌÖÎÁ ÂÙÔØ ÓÏÚÄÁÎÁ. óÐÏÓÏ Create ÐÒÅÄÐÏÌÁÇÁÅÔ ×ÙÚÏ× ÍÅÔÏÄÁ Create() Ó ÕËÁÚÁÎÉÅÍ ÎÅÏÂÈÏÄÉÍÏÇÏ ÄÒÁÊ×ÅÒÁ, Á ÚÁÔÅÍ ÎÅÐÏÓÒÅÄÓÔ×ÅÎÎÏÊ ÚÁÐÉÓØÀ ×ÓÅÈ ÍÅÔÁÄÁÎÎÙÈ É ÉÚÏÂÒÁÖÅÎÉÑ ÓÏÏÔ×ÅÔÓÔ×ÕÀÝÉÍÉ ÏÔÄÅÌØÎÙÍÉ ×ÙÚÏ×ÁÍÉ. ÷ÓÅ ÄÒÁÊ×ÅÒÙ, ËÏÔÏÒÙÅ ÍÏÇÕÔ ÓÏÚÄÁ×ÁÔØ ÎÏ×ÙÅ ÆÁÊÌÙ, ÐÏÄÄÅÒÖÉ×ÁÀÔ ÍÅÔÏÄ CreateCopy(), ÏÄÎÁËÏ ÎÅ ×ÓÅ ÐÏÄÄÅÒÖÉ×ÁÀÔ ÍÅÔÏÄ Create().
äÌÑ ÔÏÇÏ, ÞÔÏÂÙ ÏÐÒÅÄÅÌÉÔØ, ËÁËÏÊ ÍÅÔÏÄ ÐÏÄÄÅÒÖÉ×ÁÅÔ ËÏÎËÒÅÔÎÙÊ ÄÒÁÊ×ÅÒ, ÍÏÖÎÏ ÐÒÏ×ÅÒÉÔØ ÍÅÔÁÄÁÎÎÙÅ DCAP_CREATE É DCAP_CREATECOPY Õ ÏÂßÅËÔÁ ÄÒÁÊ×ÅÒÁ. õÂÅÄÉÔÅÓØ, ÞÔÏ ÆÕÎËÃÉÑ GDALAllRegister() ÂÙÌÁ ×ÙÚ×ÁÎÁ ÐÒÅÖÄÅ, ÞÅÍ ×ÙÚÙ×ÁÔØ ÆÕÎËÃÉÀ GetDriverByName(). îÁ ÐÒÉÍÅÒÅ:
îÁ ÑÚÙËÅ C++:
#include "cpl_string.h" ... const char *pszFormat = "GTiff"; GDALDriver *poDriver; char **papszMetadata; poDriver = GetGDALDriverManager()->GetDriverByName(pszFormat); if( poDriver == NULL ) exit( 1 ); papszMetadata = poDriver->GetMetadata(); if( CSLFetchBoolean( papszMetadata, GDAL_DCAP_CREATE, FALSE ) ) printf( "äÒÁÊ×ÅÒ %s ÐÏÄÄÅÒÖÉ×ÁÅÔ ÍÅÔÏÄ Create().\n", pszFormat ); if( CSLFetchBoolean( papszMetadata, GDAL_DCAP_CREATECOPY, FALSE ) ) printf( "äÒÁÊ×ÅÒ %s ÐÏÄÄÅÒÖÉ×ÁÅÔ ÍÅÔÏÄ CreateCopy().\n", pszFormat );
îÁ ÑÚÙËÅ C:
#include "cpl_string.h" ... const char *pszFormat = "GTiff"; GDALDriver hDriver = GDALGetDriverByName( pszFormat ); char **papszMetadata; if( hDriver == NULL ) exit( 1 ); papszMetadata = GDALGetMetadata( hDriver, NULL ); if( CSLFetchBoolean( papszMetadata, GDAL_DCAP_CREATE, FALSE ) ) printf( "äÒÁÊ×ÅÒ %s ÐÏÄÄÅÒÖÉ×ÁÅÔ ÍÅÔÏÄ Create().\n", pszFormat ); if( CSLFetchBoolean( papszMetadata, GDAL_DCAP_CREATECOPY, FALSE ) ) printf( "äÒÁÊ×ÅÒ %s ÐÏÄÄÅÒÖÉ×ÁÅÔ ÍÅÔÏÄ CreateCopy().\n", pszFormat );
îÁ ÑÚÙËÅ Python:
format = "GTiff" driver = gdal.GetDriverByName( format ) metadata = driver.GetMetadata() if metadata.has_key(gdal.DCAP_CREATE) \ and metadata[gdal.DCAP_CREATE] == 'YES': print 'äÒÁÊ×ÅÒ %s ÐÏÄÄÅÒÖÉ×ÁÅÔ ÍÅÔÏÄ Create().' % format if metadata.has_key(gdal.DCAP_CREATECOPY) \ and metadata[gdal.DCAP_CREATECOPY] == 'YES': print 'äÒÁÊ×ÅÒ %s ÐÏÄÄÅÒÖÉ×ÁÅÔ ÍÅÔÏÄ CreateCopy().' % format
úÁÍÅÔÉÍ, ÞÔÏ ÎÅËÏÔÏÒÙÅ ÄÒÁÊ×ÅÒÙ ÍÏÇÕÔ ÔÏÌØËÏ ÞÉÔÁÔØ ÄÁÎÎÙÅ É ÎÅ ÐÏÄÄÅÒÖÉ×ÁÀÔ ÎÉ ÍÅÔÏÄ Create(), ÎÉ CreateCopy().
îÁ ÑÚÙËÅ C++:
GDALDataset *poSrcDS = (GDALDataset *) GDALOpen( pszSrcFilename, GA_ReadOnly ); GDALDataset *poDstDS; poDstDS = poDriver->CreateCopy( pszDstFilename, poSrcDS, FALSE, NULL, NULL, NULL ); if( poDstDS != NULL ) delete poDstDS;
îÁ ÑÚÙËÅ C:
GDALDatasetH hSrcDS = GDALOpen( pszSrcFilename, GA_ReadOnly );
GDALDatasetH hDstDS;
hDstDS = GDALCreateCopy( hDriver, pszDstFilename, hSrcDS, FALSE,
NULL, NULL, NULL );
if( hDstDS != NULL )
GDALClose( hDstDS );
îÁ ÑÚÙËÅ Python:
src_ds = gdal.Open( src_filename ) dst_ds = driver.CreateCopy( dst_filename, src_ds, 0 )
úÁÍÅÔÉÍ, ÞÔÏ ÍÅÔÏÄ CreateCopy() ×ÏÚ×ÒÁÝÁÅÔ ÎÁÂÏÒ ÄÁÎÎÙÈ, ÐÒÉÇÏÄÎÙÊ ÄÌÑ ÚÁÐÉÓÉ É ÏÎ ÄÏÌÖÅÎ ÂÙÔØ ÓÏÏÔ×ÅÔÓÔ×ÕÀÝÉÍ ÏÂÒÁÚÏÍ ÚÁËÒÙÔ ÄÌÑ ÚÁ×ÅÒÛÅÎÉÑ ÚÁÐÉÓÉ É ÓÂÒÏÓÁ ÄÁÎÎÙÈ ÎÁ ÄÉÓË. ÷ ÓÌÕÞÁÅ ÑÚÙËÁ Python ÜÔÏ ÐÒÏÉÚÏÊÄ£Ô Á×ÔÏÍÁÔÉÞÅÓËÉ, ËÏÇÄÁ "dst_ds" ×ÙÊÄÅÔ ÉÚ ÏÂÌÁÓÔÉ ×ÉÄÉÍÏÓÔÉ. úÎÁÞÅÎÉÅ FALSE (ÉÌÉ 0), ÉÓÐÏÌØÚÕÅÍÏÅ ÄÌÑ ÐÁÒÁÍÅÔÒÁ bStrict, ÓÌÅÄÕÀÝÅÇÏ ÓÒÁÚÕ ÚÁ ÉÍÅÎÅÍ ×ÙÈÏÄÎÏÇÏ ÎÁÂÏÒÁ ÄÁÎÎÙÈ × ×ÙÚÏ×Å CreateCopy(), ÐÏËÁÚÙ×ÁÅÔ, ÞÔÏ CreateCopy() ÄÏÌÖÅÎ ÚÁ×ÅÒÛÉÔØÓÑ ÂÅÚ ÆÁÔÁÌØÎÏÊ ÏÛÉÂËÉ ÄÁÖÅ × ÓÌÕÞÁÅ, ÅÓÌÉ ÓÏÚÄÁ×ÁÅÍÙÊ ÎÁÂÏÒ ÄÁÎÎÙÈ ÎÅ ÍÏÖÅÔ ÂÙÔØ ÉÄÅÎÔÉÞÅÎ ×ÈÏÄÎÏÍÕ ÎÁÂÏÒÕ. ôÁËÏÅ ÍÏÖÅÔ ÐÒÏÉÚÏÊÔÉ, ÎÁÐÒÉÍÅÒ, ÐÏÓËÏÌØËÕ ×ÙÈÏÄÎÏÊ ÆÏÒÍÁÔ ÎÅ ÐÏÄÄÅÒÖÉ×ÁÅÔ ÔÉÐ ÄÁÎÎÙÈ ×ÈÏÄÎÏÇÏ ÆÏÒÍÁÔÁ, ÉÌÉ ÐÏÔÏÍÕ, ÞÔÏ ×ÙÈÏÄÎÏÊ ÆÏÒÍÁÔ ÎÅ ÐÏÄÄÅÒÖÉ×ÁÅÔ ÇÅÏÇÒÁÆÉÞÅÓËÕÀ ÐÒÉ×ÑÚËÕ.
âÏÌÅÅ ÓÌÏÖÎÙÊ ÓÌÕÞÁÊ ÍÏÖÅÔ ×ËÌÀÞÁÔØ ÕËÁÚÁÎÉÅ ÐÁÒÁÍÅÔÒÏ× ÄÌÑ ÓÏÚÄÁÎÉÑ ×ÙÈÏÄÎÏÇÏ ÆÁÊÌÁ É ÉÓÐÏÌØÚÏ×ÁÎÉÅ ÉÎÄÉËÁÔÏÒÁ ÈÏÄÁ ÒÁÂÏÔÙ:
îÁ ÑÚÙËÅ C++:
#include "cpl_string.h" ... const char **papszOptions = NULL; papszOptions = CSLSetNameValue( papszOptions, "TILED", "YES" ); papszOptions = CSLSetNameValue( papszOptions, "COMPRESS", "PACKBITS" ); poDstDS = poDriver->CreateCopy( pszDstFilename, poSrcDS, FALSE, papzOptions, GDALTermProgress, NULL ); if( poDstDS != NULL ) delete poDstDS;
îÁ ÑÚÙËÅ C:
#include "cpl_string.h" ... const char **papszOptions = NULL; papszOptions = CSLSetNameValue( papszOptions, "TILED", "YES" ); papszOptions = CSLSetNameValue( papszOptions, "COMPRESS", "PACKBITS" ); hDstDS = GDALCreateCopy( hDriver, pszDstFilename, hSrcDS, FALSE, papzOptions, GDALTermProgres, NULL ); if( hDstDS != NULL ) GDALClose( hDstDS );
îÁ ÑÚÙËÅ Python:
src_ds = gdal.Open( src_filename ) dst_ds = driver.CreateCopy( dst_filename, src_ds, 0, [ 'TILED=YES', 'COMPRESS=PACKBITS' ] )
îÁ ÑÚÙËÅ C++:
GDALDataset *poDstDS;
char **papszOptions = NULL;
poDstDS = poDriver->Create( pszDstFilename, 512, 512, 1, GDT_Byte,
papszOptions );
îÁ ÑÚÙËÅ C:
GDALDatasetH hDstDS;
char **papszOptions = NULL;
hDstDS = GDALCreate( hDriver, pszDstFilename, 512, 512, 1, GDT_Byte,
papszOptions );
îÁ ÑÚÙËÅ Python:
dst_ds = driver.Create( dst_filename, 512, 512, 1, gdal.GDT_Byte )
ëÁË ÔÏÌØËÏ ÎÁÂÏÒ ÄÁÎÎÙÈ ÂÕÄÅÔ ÕÓÐÅÛÎÏ ÓÏÚÄÁÎ, ×ÓÅ ÎÅÏÂÈÏÄÉÍÙÅ ÍÅÔÁÄÁÎÎÙÅ É ÓÏÂÓÔ×ÅÎÎÏ ÉÚÏÂÒÁÖÅÎÉÅ ÄÏÌÖÎÙ ÂÙÔØ ÚÁÐÉÓÁÎÙ × ÆÁÊÌ. ëÏÎËÒÅÔÎÁÑ ÒÅÁÌÉÚÁÃÉÑ ÏÞÅÎØ ÓÉÌØÎÏ ÚÁ×ÉÓÉÔ ÏÔ ÚÁÄÁÞÉ, ÎÏ × ÐÒÏÓÔÅÊÛÅÍ ÓÌÕÞÁÅ, ×ËÌÀÞÁÀÝÅÍ ÚÁÐÉÓØ ÐÒÏÅËÃÉÉ, ÇÅÏÇÒÁÆÉÞÅÓËÏÊ ÐÒÉ×ÑÚËÉ É ÒÁÓÔÒÏ×ÏÇÏ ÉÚÏÂÒÁÖÅÎÉÑ, ÍÏÖÅÔ ×ÙÇÌÑÄÅÔØ ÔÁË:
îÁ ÑÚÙËÅ C++:
double adfGeoTransform[6] = { 444720, 30, 0, 3751320, 0, -30 }; OGRSpatialReference oSRS; char *pszSRS_WKT = NULL; GDALRasterBand *poBand; GByte abyRaster[512*512]; poDstDS->SetGeoTransform( adfGeoTransform ); oSRS.SetUTM( 11, TRUE ); oSRS.SetWellKnownGeogCS( "NAD27" ); oSRS.exportToWkt( &pszSRS_WKT ); poDstDS->SetProjection( pszSRS_WKT ); CPLFree( pszSRS_WKT ); poBand = poDstDS->GetRasterBand(1); poBand->RasterIO( GF_Write, 0, 0, 512, 512, abyRaster, 512, 512, GDT_Byte, 0, 0 ); delete poDstDS;
îÁ ÑÚÙËÅ C:
double adfGeoTransform[6] = { 444720, 30, 0, 3751320, 0, -30 }; OGRSpatialReferenceH hSRS; char *pszSRS_WKT = NULL; GDALRasterBandH hBand; GByte abyRaster[512*512]; GDALSetGeoTransform( hDstDS, adfGeoTransform ); hSRS = OSRNewSpatialReference( NULL ); OSRSetUTM( hSRS, 11, TRUE ); OSRSetWellKnownGeogCS( hSRS, "NAD27" ); OSRExportToWkt( hSRS, &pszSRS_WKT ); OSRDestroySpatialReference( hSRS ); GDALSetProjection( hDstDS, pszSRS_WKT ); CPLFree( pszSRS_WKT ); hBand = GDALGetRasterBand( hDstDS, 1 ); GDALRasterIO( hBand, GF_Write, 0, 0, 512, 512, abyRaster, 512, 512, GDT_Byte, 0, 0 ); GDALClose( hDstDS );
îÁ ÑÚÙËÅ Python:
import Numeric, osr
dst_ds.SetGeoTransform( [ 444720, 30, 0, 3751320, 0, -30 ] )
srs = osr.SpatialReference()
srs.SetUTM( 11, 1 )
srs.SetWellKnownGeogCS( 'NAD27' )
dst_ds.SetProjection( srs.ExportToWkt() )
raster = Numeric.zeros( (512, 512) )
dst_ds.GetRasterBand(1).WriteArray( raster )