gdal_merge.py 文件源码

def raster_copy_with_nodata( s_fh, s_xoff, s_yoff, s_xsize, s_ysize, s_band_n,
                             t_fh, t_xoff, t_yoff, t_xsize, t_ysize, t_band_n,
                             nodata ):
    try:
        import numpy as Numeric
    except ImportError:
        import Numeric

    s_band = s_fh.GetRasterBand( s_band_n )
    t_band = t_fh.GetRasterBand( t_band_n )

    data_src = s_band.ReadAsArray( s_xoff, s_yoff, s_xsize, s_ysize,
                                   t_xsize, t_ysize )
    data_dst = t_band.ReadAsArray( t_xoff, t_yoff, t_xsize, t_ysize )

    nodata_test = Numeric.equal(data_src,nodata)
    to_write = Numeric.choose( nodata_test, (data_src, data_dst) )

    t_band.WriteArray( to_write, t_xoff, t_yoff )

    return 0

# =============================================================================