[postgis-users] st_aspng and blob image

[Francesco Geri]

Hello everybody.
I have some problems with st_aspng and st_asraster. I would try to
    generate a raster image from a vector polygon and view this with a
    php script. 
Following the example in the postgis documentation:


SELECT ST_AsPNG(ST_AsRaster(ST_Buffer(ST_Point(1,5),10),150, 150, '2BUI'));
this generate a binary sequence (blob) but when I try to view it in
    a web browser I obtain the follow error message

Warning: imagecreatefromstring() [function.imagecreatefromstring]: Data is not in a recognized format

This is my script:

header('Content-Type: image/png');
$query_finale="SELECT
    ST_AsPNG(ST_AsRaster(ST_Buffer(ST_Point(1,5),10),10, 10, '2BUI'));"
$finale_result_raster=pg_query($conn,$query_finale);
$final_result= pg_query($conn,$query_finale);
$img_raster=pg_fetch_array($final_result);
$immagine=$img_raster['immagine'];
imagepng($immagine);

does anyone know why it doesn't work?

Thanks!!!

Francesco
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