Re: problem with spatial subset

negra wrote:
>   Hello all!
> 
> Could anybody help me with spatial subsetting one image by another in 
> idl. It's easy in Envi, but I must process a large number of files.
> 
> Thanks!
> Gulshat
> *** Sent From/Enviado desde:     http://groups.expo.st
***
> 
> 

Hi,
you can follow these steps in IDL:

get access to ENVI's functions: envi, /restore_base_save_files
     				envi_batch_init
Open your mask image: ENVI_OPEN_FILE
Get the map information:  ENVI_GET_MAP_INFO
Extract the corners coordinates from the map info.
Open your image to subset
get the data of the image to subset: read_binary
change the mask coordinates to the image coordinates (geographical 
coords to column/row coordinates): ENVI_CONVERT_FILE_COORDINATES
Now subset the image: sub = image[x[0]:x[1],y[0]:y[1]]
Save the data: ENVI_WRITE_ENVI_FILE   (you might want to do a 
envi_file_query on the mask image AND on the original image to get the 
proper header values)

Jean