GDALDataset *SDTSDataset::Open( GDALOpenInfo * poOpenInfo )
{
int i;
/* -------------------------------------------------------------------- */
/* Before trying SDTSOpen() we first verify that the first */
/* record is in fact a SDTS file descriptor record. */
/* -------------------------------------------------------------------- */
char *pachLeader = (char *) poOpenInfo->pabyHeader;
if( poOpenInfo->nHeaderBytes < 24 )
return NULL;
if( pachLeader[5] != '1' && pachLeader[5] != '2' && pachLeader[5] != '3' )
return NULL;
if( pachLeader[6] != 'L' )
return NULL;
if( pachLeader[8] != '1' && pachLeader[8] != ' ' )
return NULL;
/* -------------------------------------------------------------------- */
/* Try opening the dataset. */
/* -------------------------------------------------------------------- */
SDTSTransfer *poTransfer = new SDTSTransfer;
if( !poTransfer->Open( poOpenInfo->pszFilename ) )
{
delete poTransfer;
return NULL;
}
/* -------------------------------------------------------------------- */
/* Confirm the requested access is supported. */
/* -------------------------------------------------------------------- */
if( poOpenInfo->eAccess == GA_Update )
{
delete poTransfer;
CPLError( CE_Failure, CPLE_NotSupported,
"The SDTS driver does not support update access to existing"
" datasets.\n" );
return NULL;
}
/* -------------------------------------------------------------------- */
/* Find the first raster layer. If there are none, abort */
/* returning an error. */
/* -------------------------------------------------------------------- */
SDTSRasterReader *poRL = NULL;
for( i = 0; i < poTransfer->GetLayerCount(); i++ )
{
if( poTransfer->GetLayerType( i ) == SLTRaster )
{
poRL = poTransfer->GetLayerRasterReader( i );
break;
}
}
if( poRL == NULL )
{
delete poTransfer;
CPLError( CE_Warning, CPLE_AppDefined,
"%s is an SDTS transfer, but has no raster cell layers.\n"
"Perhaps it is a vector transfer?\n",
poOpenInfo->pszFilename );
return NULL;
}
/* -------------------------------------------------------------------- */
/* Initialize a corresponding GDALDataset. */
/* -------------------------------------------------------------------- */
SDTSDataset *poDS = new SDTSDataset();
poDS->poTransfer = poTransfer;
poDS->poRL = poRL;
/* -------------------------------------------------------------------- */
/* Capture some information from the file that is of interest. */
/* -------------------------------------------------------------------- */
poDS->nRasterXSize = poRL->GetXSize();
poDS->nRasterYSize = poRL->GetYSize();
/* -------------------------------------------------------------------- */
/* Create band information objects. */
/* -------------------------------------------------------------------- */
poDS->nBands = 1;
poDS->papoBands = (GDALRasterBand **)
VSICalloc(sizeof(GDALRasterBand *),poDS->nBands);
for( i = 0; i < poDS->nBands; i++ )
poDS->SetBand( i+1, new SDTSRasterBand( poDS, i+1, poRL ) );
/* -------------------------------------------------------------------- */
/* Try to establish the projection string. For now we only */
/* support UTM and GEO. */
/* -------------------------------------------------------------------- */
OGRSpatialReference oSRS;
SDTS_XREF *poXREF = poTransfer->GetXREF();
if( EQUAL(poXREF->pszSystemName,"UTM") )
{
oSRS.SetUTM( poXREF->nZone );
}
else if( EQUAL(poXREF->pszSystemName,"GEO") )
{
/* we set datum later */
}
else
oSRS.SetLocalCS( poXREF->pszSystemName );
if( oSRS.IsLocal() )
/* don't try to set datum. */;
else if( EQUAL(poXREF->pszDatum,"NAS") )
oSRS.SetWellKnownGeogCS( "NAD27" );
else if( EQUAL(poXREF->pszDatum, "NAX") )
oSRS.SetWellKnownGeogCS( "NAD83" );
else if( EQUAL(poXREF->pszDatum, "WGC") )
oSRS.SetWellKnownGeogCS( "WGS72" );
else if( EQUAL(poXREF->pszDatum, "WGE") )
oSRS.SetWellKnownGeogCS( "WGS84" );
else
oSRS.SetWellKnownGeogCS( "WGS84" );
oSRS.Fixup();
poDS->pszProjection = NULL;
if( oSRS.exportToWkt( &poDS->pszProjection ) != OGRERR_NONE )
poDS->pszProjection = CPLStrdup("");
/* -------------------------------------------------------------------- */
/* Get metadata from the IDEN file. */
/* -------------------------------------------------------------------- */
const char* pszIDENFilePath = poTransfer->GetCATD()->GetModuleFilePath("IDEN");
if (pszIDENFilePath)
{
DDFModule oIDENFile;
if( oIDENFile.Open( pszIDENFilePath ) )
{
DDFRecord* poRecord;
while( (poRecord = oIDENFile.ReadRecord()) != NULL )
{
if( poRecord->GetStringSubfield( "IDEN", 0, "MODN", 0 ) == NULL )
continue;
static const char* fields[][2] = { { "TITL", "TITLE" },
{ "DAID", "DATASET_ID" },
{ "DAST", "DATA_STRUCTURE" },
{ "MPDT", "MAP_DATE" },
{ "DCDT", "DATASET_CREATION_DATE" } };
for (i = 0; i < (int)sizeof(fields) / (int)sizeof(fields[0]) ; i++)
{
const char* pszFieldValue =
poRecord->GetStringSubfield( "IDEN", 0, fields[i][0], 0 );
if ( pszFieldValue )
poDS->SetMetadataItem(fields[i][1], pszFieldValue);
}
break;
}
}
}
/* -------------------------------------------------------------------- */
/* Initialize any PAM information. */
/* -------------------------------------------------------------------- */
poDS->SetDescription( poOpenInfo->pszFilename );
poDS->TryLoadXML();
return( poDS );
}
GDALDataset *BTDataset::Open( GDALOpenInfo * poOpenInfo )
{
/* -------------------------------------------------------------------- */
/* Verify that this is some form of binterr file. */
/* -------------------------------------------------------------------- */
if( poOpenInfo->nHeaderBytes < 256)
return NULL;
if( !STARTS_WITH((const char *) poOpenInfo->pabyHeader, "binterr") )
return NULL;
/* -------------------------------------------------------------------- */
/* Create the dataset. */
/* -------------------------------------------------------------------- */
BTDataset *poDS = new BTDataset();
memcpy( poDS->abyHeader, poOpenInfo->pabyHeader, 256 );
/* -------------------------------------------------------------------- */
/* Get the version. */
/* -------------------------------------------------------------------- */
char szVersion[4] = {};
strncpy( szVersion, (char *) (poDS->abyHeader + 7), 3 );
szVersion[3] = '\0';
poDS->nVersionCode = static_cast<int>(CPLAtof(szVersion) * 10);
/* -------------------------------------------------------------------- */
/* Extract core header information, being careful about the */
/* version. */
/* -------------------------------------------------------------------- */
GInt32 nIntTemp = 0;
memcpy( &nIntTemp, poDS->abyHeader + 10, 4 );
poDS->nRasterXSize = CPL_LSBWORD32( nIntTemp );
memcpy( &nIntTemp, poDS->abyHeader + 14, 4 );
poDS->nRasterYSize = CPL_LSBWORD32( nIntTemp );
if( !GDALCheckDatasetDimensions(poDS->nRasterXSize, poDS->nRasterYSize) )
{
delete poDS;
return NULL;
}
GInt16 nDataSize = 0;
memcpy( &nDataSize, poDS->abyHeader+18, 2 );
nDataSize = CPL_LSBWORD16( nDataSize );
GDALDataType eType = GDT_Unknown;
if( poDS->abyHeader[20] != 0 && nDataSize == 4 )
eType = GDT_Float32;
else if( poDS->abyHeader[20] == 0 && nDataSize == 4 )
eType = GDT_Int32;
else if( poDS->abyHeader[20] == 0 && nDataSize == 2 )
eType = GDT_Int16;
else
{
CPLError( CE_Failure, CPLE_AppDefined,
".bt file data type unknown, got datasize=%d.",
nDataSize );
delete poDS;
return NULL;
}
/*
rcg, apr 7/06: read offset 62 for vert. units.
If zero, assume 1.0 as per spec.
*/
memcpy( &poDS->m_fVscale, poDS->abyHeader + 62, 4 );
CPL_LSBPTR32(&poDS->m_fVscale);
if(poDS->m_fVscale == 0.0f)
poDS->m_fVscale = 1.0f;
/* -------------------------------------------------------------------- */
/* Try to read a .prj file if it is indicated. */
/* -------------------------------------------------------------------- */
OGRSpatialReference oSRS;
if( poDS->nVersionCode >= 12 && poDS->abyHeader[60] != 0 )
{
const char *pszPrjFile = CPLResetExtension( poOpenInfo->pszFilename,
"prj" );
VSILFILE *fp = VSIFOpenL( pszPrjFile, "rt" );
if( fp != NULL )
{
const int nBufMax = 10000;
char *pszBuffer = static_cast<char *>(CPLMalloc(nBufMax));
const int nBytes =
static_cast<int>(VSIFReadL( pszBuffer, 1, nBufMax-1, fp ));
CPL_IGNORE_RET_VAL(VSIFCloseL( fp ));
pszBuffer[nBytes] = '\0';
char *pszBufPtr = pszBuffer;
if( oSRS.importFromWkt( &pszBufPtr ) != OGRERR_NONE )
{
CPLError( CE_Warning, CPLE_AppDefined,
"Unable to parse .prj file, "
"coordinate system missing." );
}
CPLFree( pszBuffer );
}
}
/* -------------------------------------------------------------------- */
/* If we didn't find a .prj file, try to use internal info. */
/* -------------------------------------------------------------------- */
if( oSRS.GetRoot() == NULL )
{
GInt16 nUTMZone = 0;
memcpy( &nUTMZone, poDS->abyHeader + 24, 2 );
nUTMZone = CPL_LSBWORD16( nUTMZone );
GInt16 nDatum = 0;
memcpy( &nDatum, poDS->abyHeader + 26, 2 );
nDatum = CPL_LSBWORD16( nDatum );
GInt16 nHUnits = 0;
memcpy( &nHUnits, poDS->abyHeader + 22, 2 );
nHUnits = CPL_LSBWORD16( nHUnits );
if( nUTMZone != 0 )
oSRS.SetUTM( std::abs(static_cast<int>(nUTMZone)), nUTMZone > 0 );
else if( nHUnits != 0 )
oSRS.SetLocalCS( "Unknown" );
if( nHUnits == 1 )
oSRS.SetLinearUnits( SRS_UL_METER, 1.0 );
else if( nHUnits == 2 )
oSRS.SetLinearUnits( SRS_UL_FOOT, CPLAtof(SRS_UL_FOOT_CONV) );
else if( nHUnits == 3 )
oSRS.SetLinearUnits( SRS_UL_US_FOOT, CPLAtof(SRS_UL_US_FOOT_CONV) );
// Translate some of the more obvious old USGS datum codes
if( nDatum == 0 )
nDatum = 6201;
else if( nDatum == 1 )
nDatum = 6209;
else if( nDatum == 2 )
nDatum = 6210;
else if( nDatum == 3 )
nDatum = 6202;
else if( nDatum == 4 )
nDatum = 6203;
else if( nDatum == 6 )
nDatum = 6222;
else if( nDatum == 7 )
nDatum = 6230;
else if( nDatum == 13 )
nDatum = 6267;
else if( nDatum == 14 )
nDatum = 6269;
else if( nDatum == 17 )
nDatum = 6277;
else if( nDatum == 19 )
nDatum = 6284;
else if( nDatum == 21 )
nDatum = 6301;
else if( nDatum == 22 )
nDatum = 6322;
else if( nDatum == 23 )
nDatum = 6326;
if( !oSRS.IsLocal() )
{
if( nDatum >= 6000 )
{
char szName[32];
snprintf( szName, sizeof(szName), "EPSG:%d", nDatum-2000 );
oSRS.SetWellKnownGeogCS( szName );
}
else
oSRS.SetWellKnownGeogCS( "WGS84" );
}
}
/* -------------------------------------------------------------------- */
/* Convert coordinate system back to WKT. */
/* -------------------------------------------------------------------- */
if( oSRS.GetRoot() != NULL )
oSRS.exportToWkt( &poDS->pszProjection );
/* -------------------------------------------------------------------- */
/* Get georeferencing bounds. */
/* -------------------------------------------------------------------- */
if( poDS->nVersionCode >= 11 )
{
double dfLeft = 0.0;
memcpy( &dfLeft, poDS->abyHeader + 28, 8 );
CPL_LSBPTR64( &dfLeft );
double dfRight = 0.0;
memcpy( &dfRight, poDS->abyHeader + 36, 8 );
CPL_LSBPTR64( &dfRight );
double dfBottom = 0.0;
memcpy( &dfBottom, poDS->abyHeader + 44, 8 );
CPL_LSBPTR64( &dfBottom );
double dfTop = 0.0;
memcpy( &dfTop, poDS->abyHeader + 52, 8 );
CPL_LSBPTR64( &dfTop );
poDS->adfGeoTransform[0] = dfLeft;
poDS->adfGeoTransform[1] = (dfRight - dfLeft) / poDS->nRasterXSize;
poDS->adfGeoTransform[2] = 0.0;
poDS->adfGeoTransform[3] = dfTop;
poDS->adfGeoTransform[4] = 0.0;
poDS->adfGeoTransform[5] = (dfBottom - dfTop) / poDS->nRasterYSize;
poDS->bGeoTransformValid = TRUE;
}
/* -------------------------------------------------------------------- */
/* Re-open the file with the desired access. */
/* -------------------------------------------------------------------- */
if( poOpenInfo->eAccess == GA_Update )
poDS->fpImage = VSIFOpenL( poOpenInfo->pszFilename, "rb+" );
else
poDS->fpImage = VSIFOpenL( poOpenInfo->pszFilename, "rb" );
if( poDS->fpImage == NULL )
{
CPLError( CE_Failure, CPLE_OpenFailed,
"Failed to re-open %s within BT driver.\n",
poOpenInfo->pszFilename );
delete poDS;
return NULL;
}
poDS->eAccess = poOpenInfo->eAccess;
/* -------------------------------------------------------------------- */
/* Create band information objects */
/* -------------------------------------------------------------------- */
poDS->SetBand( 1, new BTRasterBand( poDS, poDS->fpImage, eType ) );
#ifdef notdef
poDS->bGeoTransformValid =
GDALReadWorldFile( poOpenInfo->pszFilename, ".wld",
poDS->adfGeoTransform );
#endif
/* -------------------------------------------------------------------- */
/* Initialize any PAM information. */
/* -------------------------------------------------------------------- */
poDS->SetDescription( poOpenInfo->pszFilename );
poDS->TryLoadXML();
/* -------------------------------------------------------------------- */
/* Check for overviews. */
/* -------------------------------------------------------------------- */
poDS->oOvManager.Initialize( poDS, poOpenInfo->pszFilename );
return poDS;
}