[gdal-dev] failing in making transparency

[ahmet temiz]

hello

I want to make nodata areas transparent.

here is what I did:

1.
$gdalinfo  -mm -noct duy_cat1.tif | grep -i 'nodata'
  NoData Value=65535

2.
 gdalwarp  -srcnodata 65535  -dstalpha duy_cat1.tif duy_cat14.tif

But, duy_cat14.tif looks full black

here is info of  outputfile(duy_cat14.tif):
~~~~~~~~~~
Driver: GTiff/GeoTIFF
Files: duy_cat14.tif
Size is 4677, 5527
Coordinate System is:
PROJCS["UTM Zone 36, Northern Hemisphere",
    GEOGCS[,
        DATUM["unknown",
            SPHEROID["unnamed",6378388,297.000000000005]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433]],
    PROJECTION["Transverse_Mercator"],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",33],
    PARAMETER["scale_factor",0.9996],
    PARAMETER["false_easting",500000],
    PARAMETER["false_northing",0],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]]]
Origin = (437192.936421879974660,4649982.939232329837978)
Pixel Size = (20.004039786776190,-20.004039786776190)
Metadata:
  AREA_OR_POINT=Area
Image Structure Metadata:
  INTERLEAVE=PIXEL
Corner Coordinates:
Upper Left  (  437192.936, 4649982.939) ( 32d14'30.03"E, 41d59'55.01"N)
Lower Left  (  437192.936, 4539420.611) ( 32d15'11.54"E, 41d 0'10.24"N)
Upper Right (  530751.831, 4649982.939) ( 33d22'16.70"E, 42d 0'1.87"N)
Lower Right (  530751.831, 4539420.611) ( 33d21'56.38"E, 41d 0'16.87"N)
Center      (  483972.383, 4594701.775) ( 32d48'28.68"E, 41d30'10.99"N)
Band 1 Block=4677x1 Type=UInt16, ColorInterp=Palette
    Computed Min/Max=0.000,65449.000
  Color Table (RGB with 65536 entries)
Band 2 Block=4677x1 Type=UInt16, ColorInterp=Alpha
    Computed Min/Max=0.000,255.000
~~~~~~~~~~~

could you tell me where the problem is ?

regards
-- 
Ahmet Temiz
Jeoloji Müh.
Planlama ve Zarar Azaltma Dairesi Başkanlığı
Bilgi ve CBS grubu
Eskişehir Yolu 10. km.
Lodumlu / Ankara
Tel : 0 312 2872680 / 1535