[gdal-dev] Problem with image overview creation in GTiff files

[Vincent Schut]

Frank Warmerdam wrote:
> Ozy Sjahputera wrote:
>> I am trying to create image overviews for a GTiff file using 
>> GDALDataset::BuildOverviews. I keep getting various errors such as:
>>
>> ERROR 1: TIFFSetField:VISUAL.tif: Cannot modify tag "Compression" 
>> while writing
> ...
>> writing
>> ERROR 1: TIFFSetField:VISUAL.tif: Cannot modify tag "TileLength" while 
>> writing
>> ERROR 1: TIFFBuildOverviews:Can not write tiles to a stripped image
>>
>>
>> Here is my code:
>>
>>    int OverviewList[5] = { 2, 4, 8, 16, 32 };
>>    CPLErr overview_err = outDS->BuildOverviews( "AVERAGE_MAGPHASE", 5, 
>> OverviewList, 0, NULL, NULL, NULL );
>>
>>
>> I have used BuildOverviews before on HFA images and they are fine. Any 
>> idea?
> 
> Ozy,
> 
> I'm surprised.  I wonder if you might have opened your file in read-only
> mode?  Can you reproduce the problem with the gdaladdo commandline program?
> 
> Best regards,

Frank,

I'm encountering this issue pretty frequently. It happens when I create 
a tiled, compressed tiff (I'm using python but apparently that doesn't 
make a difference), write tile data into it, and then call the 
buildOverviews method. I thought I'd reported this issue (at least to 
this list), but it might have slipped my mind. Because I've found and by 
default implemented a fairly simple workaround, I totally forgot about 
it till now. The workaround is simple: first close and reopen the 
dataset, then buildOverviews. Haven't tried if flushing instead of 
reopening is enough.
Should I file a ticket on this?

Vincent.