wkblify_raster_header()

raster2pgsql.wkblify_raster_header	(		options,
			ds,
			level,
			ulp,
			xsize = None,
			ysize = None
	)

Writes WKT Raster header based on given GDAL into HEX-encoded WKB.

Definition at line 670 of file raster2pgsql.py.

def wkblify_raster_header(options, ds, level, ulp, xsize = None, ysize = None):
    """Writes WKT Raster header based on given GDAL into HEX-encoded WKB."""
    assert ds is not None, "Error: Missing GDAL dataset"
    assert level >= 1
    assert len(ulp) == 2, "Error: invalid upper-left corner"
 
    if xsize is None or ysize is None:
        assert xsize is None and ysize is None
        xsize = ds.RasterXSize
        ysize = ds.RasterYSize
 
    # Collect GeoReference information
    gt = get_gdal_geotransform(ds)
    ul = calculate_geoxy(gt, (ulp[0], ulp[1]))
    rt_ip = ( ul[0], ul[1] )
    rt_skew = ( gt[2], gt[4] )
    rt_scale = ( gt[1] * level, gt[5] * level )
    
    # TODO: Any way to lookup for SRID based on SRS in WKT?
    #srs = osr.SpatialReference()
    #srs.ImportFromWkt(ds.GetProjection())
 
    # Burn input raster as WKTRaster WKB format
    hexwkb = ''
    
    hexwkb += wkblify('B', options.endian)
    
    hexwkb += wkblify('H', options.version)
    
    if options.band is not None and options.band > 0:
        hexwkb += wkblify('H', 1)
    else:
        hexwkb += wkblify('H', ds.RasterCount)
    check_hex(hexwkb, 5)
    
    hexwkb += wkblify('d', rt_scale[0])
    hexwkb += wkblify('d', rt_scale[1])
    hexwkb += wkblify('d', rt_ip[0])
    hexwkb += wkblify('d', rt_ip[1])
    hexwkb += wkblify('d', rt_skew[0])
    hexwkb += wkblify('d', rt_skew[1])
    hexwkb += wkblify('i', options.srid)
    check_hex(hexwkb, 57)
    
    hexwkb += wkblify('H', xsize)
    hexwkb += wkblify('H', ysize)
    check_hex(hexwkb, 61)
 
    logit("MSG: Georeference: px = %s -> ul = %s \tresolution = %s \trotation = %s\n" \
          % (str(ulp), str(rt_ip), str(rt_scale), str(rt_skew)))
    return hexwkb