Example #1
0
int msSaveImageGDAL( mapObj *map, imageObj *image, char *filename )

{
  int  bFileIsTemporary = MS_FALSE;
  GDALDatasetH hMemDS, hOutputDS;
  GDALDriverH  hMemDriver, hOutputDriver;
  int          nBands = 1;
  int          iLine;
  GByte       *pabyAlphaLine = NULL;
  char        **papszOptions = NULL;
  outputFormatObj *format = image->format;
  rasterBufferObj rb;
  GDALDataType eDataType = GDT_Byte;
  int bUseXmp = MS_FALSE;

  msGDALInitialize();
  memset(&rb,0,sizeof(rasterBufferObj));

#ifdef USE_EXEMPI
  if( map != NULL ) {
    bUseXmp = msXmpPresent(map);
  }
#endif


  /* -------------------------------------------------------------------- */
  /*      Identify the proposed output driver.                            */
  /* -------------------------------------------------------------------- */
  msAcquireLock( TLOCK_GDAL );
  hOutputDriver = GDALGetDriverByName( format->driver+5 );
  if( hOutputDriver == NULL ) {
    msReleaseLock( TLOCK_GDAL );
    msSetError( MS_MISCERR, "Failed to find %s driver.",
                "msSaveImageGDAL()", format->driver+5 );
    return MS_FAILURE;
  }

  /* -------------------------------------------------------------------- */
  /*      We will need to write the output to a temporary file and        */
  /*      then stream to stdout if no filename is passed.  If the         */
  /*      driver supports virtualio then we hold the temporary file in    */
  /*      memory, otherwise we try to put it in a reasonable temporary    */
  /*      file location.                                                  */
  /* -------------------------------------------------------------------- */
  if( filename == NULL ) {
    const char *pszExtension = format->extension;
    if( pszExtension == NULL )
      pszExtension = "img.tmp";

    if( bUseXmp == MS_FALSE && GDALGetMetadataItem( hOutputDriver, GDAL_DCAP_VIRTUALIO, NULL )
        != NULL ) {
      CleanVSIDir( "/vsimem/msout" );
      filename = msTmpFile(map, NULL, "/vsimem/msout/", pszExtension );
    }

    if( filename == NULL && map != NULL)
      filename = msTmpFile(map, map->mappath,NULL,pszExtension);
    else if( filename == NULL ) {
      filename = msTmpFile(map, NULL, NULL, pszExtension );
    }

    bFileIsTemporary = MS_TRUE;
  }

  /* -------------------------------------------------------------------- */
  /*      Establish the characteristics of our memory, and final          */
  /*      dataset.                                                        */
  /* -------------------------------------------------------------------- */

  if( format->imagemode == MS_IMAGEMODE_RGB ) {
    nBands = 3;
    assert( MS_RENDERER_PLUGIN(format) && format->vtable->supports_pixel_buffer );
    format->vtable->getRasterBufferHandle(image,&rb);
  } else if( format->imagemode == MS_IMAGEMODE_RGBA ) {
    pabyAlphaLine = (GByte *) calloc(image->width,1);
    if (pabyAlphaLine == NULL) {
      msReleaseLock( TLOCK_GDAL );
      msSetError( MS_MEMERR, "Out of memory allocating %u bytes.\n", "msSaveImageGDAL()", image->width);
      return MS_FAILURE;
    }
    nBands = 4;
    assert( MS_RENDERER_PLUGIN(format) && format->vtable->supports_pixel_buffer );
    format->vtable->getRasterBufferHandle(image,&rb);
  } else if( format->imagemode == MS_IMAGEMODE_INT16 ) {
    nBands = format->bands;
    eDataType = GDT_Int16;
  } else if( format->imagemode == MS_IMAGEMODE_FLOAT32 ) {
    nBands = format->bands;
    eDataType = GDT_Float32;
  } else if( format->imagemode == MS_IMAGEMODE_BYTE ) {
    nBands = format->bands;
    eDataType = GDT_Byte;
  } else {
#ifdef USE_GD
    assert( format->imagemode == MS_IMAGEMODE_PC256
            && format->renderer == MS_RENDER_WITH_GD );
#else
    {
      msReleaseLock( TLOCK_GDAL );
      msSetError( MS_MEMERR, "GD not compiled in. This is a bug.", "msSaveImageGDAL()");
      return MS_FAILURE;
    }
#endif

  }

  /* -------------------------------------------------------------------- */
  /*      Create a memory dataset which we can use as a source for a      */
  /*      CreateCopy().                                                   */
  /* -------------------------------------------------------------------- */
  hMemDriver = GDALGetDriverByName( "MEM" );
  if( hMemDriver == NULL ) {
    msReleaseLock( TLOCK_GDAL );
    msSetError( MS_MISCERR, "Failed to find MEM driver.",
                "msSaveImageGDAL()" );
    return MS_FAILURE;
  }

  hMemDS = GDALCreate( hMemDriver, "msSaveImageGDAL_temp",
                       image->width, image->height, nBands,
                       eDataType, NULL );
  if( hMemDS == NULL ) {
    msReleaseLock( TLOCK_GDAL );
    msSetError( MS_MISCERR, "Failed to create MEM dataset.",
                "msSaveImageGDAL()" );
    return MS_FAILURE;
  }

  /* -------------------------------------------------------------------- */
  /*      Copy the gd image into the memory dataset.                      */
  /* -------------------------------------------------------------------- */
  for( iLine = 0; iLine < image->height; iLine++ ) {
    int iBand;

    for( iBand = 0; iBand < nBands; iBand++ ) {
      GDALRasterBandH hBand = GDALGetRasterBand( hMemDS, iBand+1 );

      if( format->imagemode == MS_IMAGEMODE_INT16 ) {
        GDALRasterIO( hBand, GF_Write, 0, iLine, image->width, 1,
                      image->img.raw_16bit + iLine * image->width
                      + iBand * image->width * image->height,
                      image->width, 1, GDT_Int16, 2, 0 );

      } else if( format->imagemode == MS_IMAGEMODE_FLOAT32 ) {
        GDALRasterIO( hBand, GF_Write, 0, iLine, image->width, 1,
                      image->img.raw_float + iLine * image->width
                      + iBand * image->width * image->height,
                      image->width, 1, GDT_Float32, 4, 0 );
      } else if( format->imagemode == MS_IMAGEMODE_BYTE ) {
        GDALRasterIO( hBand, GF_Write, 0, iLine, image->width, 1,
                      image->img.raw_byte + iLine * image->width
                      + iBand * image->width * image->height,
                      image->width, 1, GDT_Byte, 1, 0 );
      }
#ifdef USE_GD
      else if(format->renderer == MS_RENDER_WITH_GD) {
        gdImagePtr img = (gdImagePtr)image->img.plugin;
        GDALRasterIO( hBand, GF_Write, 0, iLine, image->width, 1,
                      img->pixels[iLine],
                      image->width, 1, GDT_Byte, 0, 0 );
      }
#endif
      else {
        GByte *pabyData;
        unsigned char *pixptr = NULL;
        assert( rb.type == MS_BUFFER_BYTE_RGBA );
        switch(iBand) {
          case 0:
            pixptr = rb.data.rgba.r;
            break;
          case 1:
            pixptr = rb.data.rgba.g;
            break;
          case 2:
            pixptr = rb.data.rgba.b;
            break;
          case 3:
            pixptr = rb.data.rgba.a;
            break;
        }
        assert(pixptr);
        if( pixptr == NULL ) {
          msReleaseLock( TLOCK_GDAL );
          msSetError( MS_MISCERR, "Missing RGB or A buffer.\n",
                      "msSaveImageGDAL()" );
          return MS_FAILURE;
        }

        pabyData = (GByte *)(pixptr + iLine*rb.data.rgba.row_step);

        if( rb.data.rgba.a == NULL || iBand == 3 ) {
          GDALRasterIO( hBand, GF_Write, 0, iLine, image->width, 1,
                        pabyData, image->width, 1, GDT_Byte,
                        rb.data.rgba.pixel_step, 0 );
        } else { /* We need to un-pre-multiple RGB by alpha. */
          GByte *pabyUPM = (GByte*) malloc(image->width);
          GByte *pabyAlpha= (GByte *)(rb.data.rgba.a + iLine*rb.data.rgba.row_step);
          int i;

          for( i = 0; i < image->width; i++ ) {
            int alpha = pabyAlpha[i*rb.data.rgba.pixel_step];

            if( alpha == 0 )
              pabyUPM[i] = 0;
            else {
              int result = (pabyData[i*rb.data.rgba.pixel_step] * 255) / alpha;

              if( result > 255 )
                result = 255;

              pabyUPM[i] = result;
            }
          }

          GDALRasterIO( hBand, GF_Write, 0, iLine, image->width, 1,
                        pabyUPM, image->width, 1, GDT_Byte, 1, 0 );
          free( pabyUPM );
        }
      }
    }
  }

  if( pabyAlphaLine != NULL )
    free( pabyAlphaLine );

  /* -------------------------------------------------------------------- */
  /*      Attach the palette if appropriate.                              */
  /* -------------------------------------------------------------------- */
#ifdef USE_GD
  if( format->renderer == MS_RENDER_WITH_GD ) {
    GDALColorEntry sEntry;
    int  iColor;
    GDALColorTableH hCT;
    gdImagePtr img = (gdImagePtr)image->img.plugin;
    hCT = GDALCreateColorTable( GPI_RGB );

    for( iColor = 0; iColor < img->colorsTotal; iColor++ ) {
      sEntry.c1 = img->red[iColor];
      sEntry.c2 = img->green[iColor];
      sEntry.c3 = img->blue[iColor];

      if( iColor == gdImageGetTransparent( img ) )
        sEntry.c4 = 0;
      else if( iColor == 0
               && gdImageGetTransparent( img ) == -1
               && format->transparent )
        sEntry.c4 = 0;
      else
        sEntry.c4 = 255;

      GDALSetColorEntry( hCT, iColor, &sEntry );
    }

    GDALSetRasterColorTable( GDALGetRasterBand( hMemDS, 1 ), hCT );

    GDALDestroyColorTable( hCT );
  } else
#endif
    if( format->imagemode == MS_IMAGEMODE_RGB ) {
      GDALSetRasterColorInterpretation(
        GDALGetRasterBand( hMemDS, 1 ), GCI_RedBand );
      GDALSetRasterColorInterpretation(
        GDALGetRasterBand( hMemDS, 2 ), GCI_GreenBand );
      GDALSetRasterColorInterpretation(
        GDALGetRasterBand( hMemDS, 3 ), GCI_BlueBand );
    } else if( format->imagemode == MS_IMAGEMODE_RGBA ) {
      GDALSetRasterColorInterpretation(
        GDALGetRasterBand( hMemDS, 1 ), GCI_RedBand );
      GDALSetRasterColorInterpretation(
        GDALGetRasterBand( hMemDS, 2 ), GCI_GreenBand );
      GDALSetRasterColorInterpretation(
        GDALGetRasterBand( hMemDS, 3 ), GCI_BlueBand );
      GDALSetRasterColorInterpretation(
        GDALGetRasterBand( hMemDS, 4 ), GCI_AlphaBand );
    }

  /* -------------------------------------------------------------------- */
  /*      Assign the projection and coordinate system to the memory       */
  /*      dataset.                                                        */
  /* -------------------------------------------------------------------- */

  if( map != NULL ) {
    char *pszWKT;

    GDALSetGeoTransform( hMemDS, map->gt.geotransform );

    pszWKT = msProjectionObj2OGCWKT( &(map->projection) );
    if( pszWKT != NULL ) {
      GDALSetProjection( hMemDS, pszWKT );
      msFree( pszWKT );
    }
  }

  /* -------------------------------------------------------------------- */
  /*      Possibly assign a nodata value.                                 */
  /* -------------------------------------------------------------------- */
  if( msGetOutputFormatOption(format,"NULLVALUE",NULL) != NULL ) {
    int iBand;
    const char *nullvalue = msGetOutputFormatOption(format,
                            "NULLVALUE",NULL);

    for( iBand = 0; iBand < nBands; iBand++ ) {
      GDALRasterBandH hBand = GDALGetRasterBand( hMemDS, iBand+1 );
      GDALSetRasterNoDataValue( hBand, atof(nullvalue) );
    }
  }

  /* -------------------------------------------------------------------- */
  /*  Try to save resolution in the output file.                          */
  /* -------------------------------------------------------------------- */
  if( image->resolution > 0 ) {
    char res[30];

    sprintf( res, "%lf", image->resolution );
    GDALSetMetadataItem( hMemDS, "TIFFTAG_XRESOLUTION", res, NULL );
    GDALSetMetadataItem( hMemDS, "TIFFTAG_YRESOLUTION", res, NULL );
    GDALSetMetadataItem( hMemDS, "TIFFTAG_RESOLUTIONUNIT", "2", NULL );
  }

  /* -------------------------------------------------------------------- */
  /*      Create a disk image in the selected output format from the      */
  /*      memory image.                                                   */
  /* -------------------------------------------------------------------- */
  papszOptions = (char**)calloc(sizeof(char *),(format->numformatoptions+1));
  if (papszOptions == NULL) {
    msReleaseLock( TLOCK_GDAL );
    msSetError( MS_MEMERR, "Out of memory allocating %u bytes.\n", "msSaveImageGDAL()",
                (unsigned int)(sizeof(char *)*(format->numformatoptions+1)));
    return MS_FAILURE;
  }

  memcpy( papszOptions, format->formatoptions,
          sizeof(char *) * format->numformatoptions );

  hOutputDS = GDALCreateCopy( hOutputDriver, filename, hMemDS, FALSE,
                              papszOptions, NULL, NULL );

  free( papszOptions );

  if( hOutputDS == NULL ) {
    GDALClose( hMemDS );
    msReleaseLock( TLOCK_GDAL );
    msSetError( MS_MISCERR, "Failed to create output %s file.\n%s",
                "msSaveImageGDAL()", format->driver+5,
                CPLGetLastErrorMsg() );
    return MS_FAILURE;
  }

  /* closing the memory DS also frees all associated resources. */
  GDALClose( hMemDS );

  GDALClose( hOutputDS );
  msReleaseLock( TLOCK_GDAL );


  /* -------------------------------------------------------------------- */
  /*      Are we writing license info into the image?                     */
  /*      If so, add it to the temp file on disk now.                     */
  /* -------------------------------------------------------------------- */
#ifdef USE_EXEMPI
  if ( bUseXmp == MS_TRUE ) {
    if( msXmpWrite(map, filename) == MS_FAILURE ) {
      /* Something bad happened. */
      msSetError( MS_MISCERR, "XMP write to %s failed.\n",
                  "msSaveImageGDAL()", filename);
      return MS_FAILURE;
    }
  }
#endif

  /* -------------------------------------------------------------------- */
  /*      Is this supposed to be a temporary file?  If so, stream to      */
  /*      stdout and delete the file.                                     */
  /* -------------------------------------------------------------------- */
  if( bFileIsTemporary ) {
    FILE *fp;
    unsigned char block[4000];
    int bytes_read;

    if( msIO_needBinaryStdout() == MS_FAILURE )
      return MS_FAILURE;

    /* We aren't sure how far back GDAL exports the VSI*L API, so
       we only use it if we suspect we need it.  But we do need it if
       holding temporary file in memory. */
    fp = VSIFOpenL( filename, "rb" );
    if( fp == NULL ) {
      msSetError( MS_MISCERR,
                  "Failed to open %s for streaming to stdout.",
                  "msSaveImageGDAL()", filename );
      return MS_FAILURE;
    }

    while( (bytes_read = VSIFReadL(block, 1, sizeof(block), fp)) > 0 )
      msIO_fwrite( block, 1, bytes_read, stdout );

    VSIFCloseL( fp );

    VSIUnlink( filename );
    CleanVSIDir( "/vsimem/msout" );

    free( filename );
  }

  return MS_SUCCESS;
}
Example #2
0
/* actual raster band export
 * returns 0 on success
 * -1 on raster data read/write error
 * */
int export_band(GDALDatasetH hMEMDS, GDALDataType export_datatype, int band,
		const char *name, const char *mapset,
		struct Cell_head *cellhead, RASTER_MAP_TYPE maptype,
		double nodataval, const char *nodatakey,
		int suppress_main_colortable, int default_nodataval)
{
    struct Colors sGrassColors;
    GDALColorTableH hCT;
    int iColor;
    int bHaveMinMax;
    double dfCellMin;
    double dfCellMax;
    struct FPRange sRange;
    int fd;
    int cols = cellhead->cols;
    int rows = cellhead->rows;
    int ret = 0;

    /* Open GRASS raster */
    fd = Rast_open_old(name, mapset);

    /* Get raster band  */
    GDALRasterBandH hBand = GDALGetRasterBand(hMEMDS, band);

    if (hBand == NULL) {
	G_warning(_("Unable to get raster band"));
	return -1;
    }

    /* Get min/max values. */
    if (Rast_read_fp_range(name, mapset, &sRange) == -1) {
	bHaveMinMax = FALSE;
    }
    else {
	bHaveMinMax = TRUE;
	Rast_get_fp_range_min_max(&sRange, &dfCellMin, &dfCellMax);
    }

    /* suppress useless warnings */
    CPLPushErrorHandler(CPLQuietErrorHandler);
    GDALSetRasterColorInterpretation(hBand, GPI_RGB);
    CPLPopErrorHandler();

    /* use default color rules if no color rules are given */
    if (Rast_read_colors(name, mapset, &sGrassColors) >= 0) {
	int maxcolor, i;
	CELL min, max;
	char key[200], value[200];
	int rcount;

	Rast_get_c_color_range(&min, &max, &sGrassColors);
	if (bHaveMinMax) {
	    if (max < dfCellMax) {
		maxcolor = max;
	    }
	    else {
		maxcolor = (int)ceil(dfCellMax);
	    }
	    if (maxcolor > GRASS_MAX_COLORS) {
		maxcolor = GRASS_MAX_COLORS;
		G_warning("Too many values, color table cut to %d entries",
			  maxcolor);
	    }
	}
	else {
	    if (max < GRASS_MAX_COLORS) {
		maxcolor = max;
	    }
	    else {
		maxcolor = GRASS_MAX_COLORS;
		G_warning("Too many values, color table set to %d entries",
			  maxcolor);
	    }
	}

	rcount = Rast_colors_count(&sGrassColors);

	G_debug(3, "dfCellMin: %f, dfCellMax: %f, maxcolor: %d", dfCellMin,
		dfCellMax, maxcolor);

	if (!suppress_main_colortable) {
	    hCT = GDALCreateColorTable(GPI_RGB);

	    for (iColor = 0; iColor <= maxcolor; iColor++) {
		int nRed, nGreen, nBlue;
		GDALColorEntry sColor;

		if (Rast_get_c_color(&iColor, &nRed, &nGreen, &nBlue,
				     &sGrassColors)) {
		    sColor.c1 = nRed;
		    sColor.c2 = nGreen;
		    sColor.c3 = nBlue;
		    sColor.c4 = 255;

		    G_debug(3,
			    "Rast_get_c_color: Y, rcount %d, nRed %d, nGreen %d, nBlue %d",
			    rcount, nRed, nGreen, nBlue);
		    GDALSetColorEntry(hCT, iColor, &sColor);
		}
		else {
		    sColor.c1 = 0;
		    sColor.c2 = 0;
		    sColor.c3 = 0;
		    sColor.c4 = 0;

		    G_debug(3,
			    "Rast_get_c_color: N, rcount %d, nRed %d, nGreen %d, nBlue %d",
			    rcount, nRed, nGreen, nBlue);
		    GDALSetColorEntry(hCT, iColor, &sColor);
		}
	    }

	    GDALSetRasterColorTable(hBand, hCT);
	}

	if (rcount > 0) {
	    /* Create metadata entries for color table rules */
	    sprintf(value, "%d", rcount);
	    GDALSetMetadataItem(hBand, "COLOR_TABLE_RULES_COUNT", value,
				NULL);
	}

	/* Add the rules in reverse order */
	/* This can cause a GDAL warning with many rules, something like
	 * Warning 1: Lost metadata writing to GeoTIFF ... too large to fit in tag. */
	for (i = rcount - 1; i >= 0; i--) {
	    DCELL val1, val2;
	    unsigned char r1, g1, b1, r2, g2, b2;

	    Rast_get_fp_color_rule(&val1, &r1, &g1, &b1, &val2, &r2, &g2, &b2,
			       &sGrassColors, i);


	    sprintf(key, "COLOR_TABLE_RULE_RGB_%d", rcount - i - 1);
	    sprintf(value, "%e %e %d %d %d %d %d %d", val1, val2, r1, g1, b1,
		    r2, g2, b2);
	    GDALSetMetadataItem(hBand, key, value, NULL);
	}
    }

    /* Create GRASS raster buffer */
    void *bufer = Rast_allocate_buf(maptype);

    if (bufer == NULL) {
	G_warning(_("Unable to allocate buffer for reading raster map"));
	return -1;
    }

    /* the following routine must be kept identical to exact_checks */

    /* Copy data form GRASS raster to GDAL raster */
    int row, col;
    int n_nulls = 0;

    /* Better use selected GDAL datatype instead of 
     * the best match with GRASS raster map types ? */

    if (maptype == FCELL_TYPE) {

	/* Source datatype understandable by GDAL */
	GDALDataType datatype = GDT_Float32;
	FCELL fnullval = (FCELL) nodataval;

	G_debug(1, "FCELL nodata val: %f", fnullval);

	for (row = 0; row < rows; row++) {

	    Rast_get_row(fd, bufer, row, maptype);
	    for (col = 0; col < cols; col++) {
		if (Rast_is_f_null_value(&((FCELL *) bufer)[col])) {
		    ((FCELL *) bufer)[col] = fnullval;
		    if (n_nulls == 0) {
			GDALSetRasterNoDataValue(hBand, nodataval);
		    }
		    n_nulls++;
		}
	    }

	    if (GDALRasterIO
		(hBand, GF_Write, 0, row, cols, 1, bufer, cols, 1, datatype,
		 0, 0) >= CE_Failure) {
		G_warning(_("Unable to write GDAL raster file"));
		return -1;
	    }
	    G_percent(row + 1, rows, 2);
	}
    }
    else if (maptype == DCELL_TYPE) {

	GDALDataType datatype = GDT_Float64;
	DCELL dnullval = (DCELL) nodataval;

	G_debug(1, "DCELL nodata val: %f", dnullval);

	for (row = 0; row < rows; row++) {

	    Rast_get_row(fd, bufer, row, maptype);
	    for (col = 0; col < cols; col++) {
		if (Rast_is_d_null_value(&((DCELL *) bufer)[col])) {
		    ((DCELL *) bufer)[col] = dnullval;
		    if (n_nulls == 0) {
			GDALSetRasterNoDataValue(hBand, nodataval);
		    }
		    n_nulls++;
		}
	    }

	    if (GDALRasterIO
		(hBand, GF_Write, 0, row, cols, 1, bufer, cols, 1, datatype,
		 0, 0) >= CE_Failure) {
		G_warning(_("Unable to write GDAL raster file"));
		return -1;
	    }
	    G_percent(row + 1, rows, 2);
	}
    }
    else {

	GDALDataType datatype = GDT_Int32;
	CELL inullval = (CELL) nodataval;

	G_debug(1, "CELL nodata val: %d", inullval);

	for (row = 0; row < rows; row++) {

	    Rast_get_row(fd, bufer, row, maptype);
	    for (col = 0; col < cols; col++) {
		if (Rast_is_c_null_value(&((CELL *) bufer)[col])) {
		    ((CELL *) bufer)[col] = inullval;
		    if (n_nulls == 0) {
			GDALSetRasterNoDataValue(hBand, nodataval);
		    }
		    n_nulls++;
		}
	    }

	    if (GDALRasterIO
		(hBand, GF_Write, 0, row, cols, 1, bufer, cols, 1, datatype,
		 0, 0) >= CE_Failure) {
		G_warning(_("Unable to write GDAL raster file"));
		return -1;
	    }
	    G_percent(row + 1, rows, 2);
	}
    }

    G_free(bufer);

    return ret;
}
bool QgsImageWarper::createDestinationDataset(
  const QString &outputName, GDALDatasetH hSrcDS, GDALDatasetH &hDstDS,
  uint resX, uint resY, double *adfGeoTransform, bool useZeroAsTrans,
  const QString& compression, const QString &projection )
{
  // create the output file
  GDALDriverH driver = GDALGetDriverByName( "GTiff" );
  if ( !driver )
  {
    return false;
  }
  char **papszOptions = NULL;
  papszOptions = CSLSetNameValue( papszOptions, "COMPRESS", compression.toAscii() );
  hDstDS = GDALCreate( driver,
                       QFile::encodeName( outputName ).constData(), resX, resY,
                       GDALGetRasterCount( hSrcDS ),
                       GDALGetRasterDataType( GDALGetRasterBand( hSrcDS, 1 ) ),
                       papszOptions );
  if ( !hDstDS )
  {
    return false;
  }

  if ( CE_None != GDALSetGeoTransform( hDstDS, adfGeoTransform ) )
  {
    return false;
  }

  if ( !projection.isEmpty() )
  {
    OGRSpatialReference oTargetSRS;
    if ( projection.startsWith( "EPSG", Qt::CaseInsensitive ) )
    {
      QString epsg = projection.mid( projection.indexOf( ":" ) + 1 );
      oTargetSRS.importFromEPSG( epsg.toInt() );
    }
    else
    {
      oTargetSRS.importFromProj4( projection.toLatin1().data() );
    }

    char *wkt = NULL;
    OGRErr err = oTargetSRS.exportToWkt( &wkt );
    if ( err != CE_None || GDALSetProjection( hDstDS, wkt ) != CE_None )
    {
      OGRFree( wkt );
      return false;
    }
    OGRFree( wkt );
  }

  for ( int i = 0; i < GDALGetRasterCount( hSrcDS ); ++i )
  {
    GDALRasterBandH hSrcBand = GDALGetRasterBand( hSrcDS, i + 1 );
    GDALRasterBandH hDstBand = GDALGetRasterBand( hDstDS, i + 1 );
    GDALColorTableH cTable = GDALGetRasterColorTable( hSrcBand );
    GDALSetRasterColorInterpretation( hDstBand, GDALGetRasterColorInterpretation( hSrcBand ) );
    if ( cTable )
    {
      GDALSetRasterColorTable( hDstBand, cTable );
    }

    int success;
    double noData = GDALGetRasterNoDataValue( hSrcBand, &success );
    if ( success )
    {
      GDALSetRasterNoDataValue( hDstBand, noData );
    }
    else if ( useZeroAsTrans )
    {
      GDALSetRasterNoDataValue( hDstBand, 0 );
    }
  }

  return true;
}
void QgsImageWarper::warp( const QString& input, const QString& output,
                           double& xOffset, double& yOffset,
                           ResamplingMethod resampling, bool useZeroAsTrans, const QString& compression )
{
  // Open input file
  GDALAllRegister();
  GDALDatasetH hSrcDS = GDALOpen( QFile::encodeName( input ).constData(), GA_ReadOnly );
  // Setup warp options.
  GDALWarpOptions *psWarpOptions = GDALCreateWarpOptions();
  psWarpOptions->hSrcDS = hSrcDS;
  psWarpOptions->nBandCount = GDALGetRasterCount( hSrcDS );
  psWarpOptions->panSrcBands =
    ( int * ) CPLMalloc( sizeof( int ) * psWarpOptions->nBandCount );
  psWarpOptions->panDstBands =
    ( int * ) CPLMalloc( sizeof( int ) * psWarpOptions->nBandCount );
  for ( int i = 0; i < psWarpOptions->nBandCount; ++i )
  {
    psWarpOptions->panSrcBands[i] = i + 1;
    psWarpOptions->panDstBands[i] = i + 1;
  }
  psWarpOptions->pfnProgress = GDALTermProgress;
  psWarpOptions->pfnTransformer = &QgsImageWarper::transform;
  psWarpOptions->eResampleAlg = GDALResampleAlg( resampling );

  // check the bounds for the warped raster
  // order: upper right, lower right, lower left (y points down)
  double x[] = { GDALGetRasterXSize( hSrcDS ), GDALGetRasterXSize( hSrcDS ), 0 };
  double y[] = { 0, GDALGetRasterYSize( hSrcDS ), GDALGetRasterYSize( hSrcDS ) };
  int s[] = { 0, 0, 0 };
  TransformParameters tParam = { mAngle, 0, 0 };
  transform( &tParam, FALSE, 3, x, y, NULL, s );
  double minX = 0, minY = 0, maxX = 0, maxY = 0;
  for ( int i = 0; i < 3; ++i )
  {
    minX = minX < x[i] ? minX : x[i];
    minY = minY < y[i] ? minY : y[i];
    maxX = maxX > x[i] ? maxX : x[i];
    maxY = maxY > y[i] ? maxY : y[i];
  }
  int newXSize = int( maxX - minX ) + 1;
  int newYSize = int( maxY - minY ) + 1;
  xOffset = -minX;
  yOffset = -minY;
  tParam.x0 = xOffset;
  tParam.y0 = yOffset;
  psWarpOptions->pTransformerArg = &tParam;

  // create the output file
  GDALDriverH driver = GDALGetDriverByName( "GTiff" );
  char **papszOptions = NULL;
  papszOptions = CSLSetNameValue( papszOptions, "INIT_DEST", "NO_DATA" );
  papszOptions = CSLSetNameValue( papszOptions, "COMPRESS", compression.toAscii() );
  GDALDatasetH hDstDS =
    GDALCreate( driver,
                QFile::encodeName( output ).constData(), newXSize, newYSize,
                GDALGetRasterCount( hSrcDS ),
                GDALGetRasterDataType( GDALGetRasterBand( hSrcDS, 1 ) ),
                papszOptions );

  for ( int i = 0; i < GDALGetRasterCount( hSrcDS ); ++i )
  {
    GDALRasterBandH hSrcBand = GDALGetRasterBand( hSrcDS, i + 1 );
    GDALRasterBandH hDstBand = GDALGetRasterBand( hDstDS, i + 1 );
    GDALColorTableH cTable = GDALGetRasterColorTable( hSrcBand );
    GDALSetRasterColorInterpretation( hDstBand, GDALGetRasterColorInterpretation( hSrcBand ) );
    if ( cTable )
    {
      GDALSetRasterColorTable( hDstBand, cTable );
    }

    double noData = GDALGetRasterNoDataValue( hSrcBand, NULL );
    if ( noData == -1e10 && useZeroAsTrans )
    {
      GDALSetRasterNoDataValue( hDstBand, 0 );
    }
    else
    {
      GDALSetRasterNoDataValue( hDstBand, noData );
    }
  }
  psWarpOptions->hDstDS = hDstDS;

  // Initialize and execute the warp operation.
  GDALWarpOperation oOperation;
  oOperation.Initialize( psWarpOptions );
  oOperation.ChunkAndWarpImage( 0, 0, GDALGetRasterXSize( hDstDS ),
                                GDALGetRasterYSize( hDstDS ) );
  GDALDestroyWarpOptions( psWarpOptions );

  GDALClose( hSrcDS );
  GDALClose( hDstDS );
}