GDALDataset *BIGGIFDataset::Open( GDALOpenInfo * poOpenInfo )
{
if( !Identify( poOpenInfo ) || poOpenInfo->fpL == NULL )
return NULL;
if( poOpenInfo->eAccess == GA_Update )
{
CPLError( CE_Failure, CPLE_NotSupported,
"The GIF driver does not support update access to existing"
" files.\n" );
return NULL;
}
/* -------------------------------------------------------------------- */
/* Create a corresponding GDALDataset. */
/* -------------------------------------------------------------------- */
BIGGIFDataset *poDS = new BIGGIFDataset();
poDS->fp = poOpenInfo->fpL;
poOpenInfo->fpL = NULL;
poDS->eAccess = GA_ReadOnly;
if( poDS->ReOpen() == CE_Failure )
{
delete poDS;
return NULL;
}
/* -------------------------------------------------------------------- */
/* Capture some information from the file that is of interest. */
/* -------------------------------------------------------------------- */
poDS->nRasterXSize = poDS->hGifFile->SavedImages[0].ImageDesc.Width;
poDS->nRasterYSize = poDS->hGifFile->SavedImages[0].ImageDesc.Height;
if( poDS->hGifFile->SavedImages[0].ImageDesc.ColorMap == NULL &&
poDS->hGifFile->SColorMap == NULL )
{
CPLDebug("GIF", "Skipping image without color table");
delete poDS;
return NULL;
}
/* -------------------------------------------------------------------- */
/* Create band information objects. */
/* -------------------------------------------------------------------- */
poDS->SetBand( 1,
new BIGGifRasterBand( poDS,
poDS->hGifFile->SBackGroundColor ));
/* -------------------------------------------------------------------- */
/* Check for georeferencing. */
/* -------------------------------------------------------------------- */
poDS->DetectGeoreferencing(poOpenInfo);
/* -------------------------------------------------------------------- */
/* Initialize any PAM information. */
/* -------------------------------------------------------------------- */
poDS->SetDescription( poOpenInfo->pszFilename );
poDS->TryLoadXML( poOpenInfo->GetSiblingFiles() );
/* -------------------------------------------------------------------- */
/* Support overviews. */
/* -------------------------------------------------------------------- */
poDS->oOvManager.Initialize( poDS, poOpenInfo->pszFilename,
poOpenInfo->GetSiblingFiles() );
return poDS;
}
