[Gdal-dev] ArcInfo Grid Read Error

[Frank Warmerdam]

Shannon Scott wrote:
> Hello,
> 
> I am new to gdal, so please forgive my ignorance.
> 
> I am trying to convert some ArcInfo Grid data to a tif.
> 
> I have been trying to use gdal_translate, but I get the following error.
> 
>  
> 
> $ gdal_translate -of GTiff dem24k_int test1.tif
> 
> Input file size is 20943, 21754
> 
> 0...10..ERROR 1: Read of 1030 bytes from offset 1260810 for grid block 
> failed.
> 
> ERROR 1: IReadBlock failed at X offset 33, Y offset 896
> 
> ERROR 1: GetBlockRef failed at X block offset 33, Y block offset 896
> 
>  
> 
> I also tried the –not_strict optin, but got the same error.  Is there 
> any way to “clean” the ArcInfo Grid ( assuming it has bad data ).  Has 
> anyone else had this problem?

Shannon,

I imagine the file is truncated from the proper length for some reason.
I don't know of a way to get the available data out with gdal_translate.
Of course, you could write your own little utility that reads the source
file block by block, and that ignores errors and continues.  Is the
grid main image file really only 1260810 bytes long or so?  It seems like
most of your data is already gone.

Best regards,

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