[gdal-dev] Re: gdalwarp -co COMPRESSION issues

[Frank Warmerdam]

Maciej Sieczka wrote:
> Jukka Rahkonen pisze:
>> Maciej Sieczka <tutey <at> o2.pl> writes:
> 
>> About BigTIFF, I guess that the error will perhaps not happen if you ask
>> gdalwarp to use it by adding -co BigTIFF=yes.
> 
> Right. I forgot it.
> 
> Anyway, it still holds true that gdalwarp produces compressed rasters 
> several times bigger than gdal_translate.
> 
> For example - fetch this RGB 290 MB ortophoto tile. It's an RGB (3 
> 8-byte bands) GeoTIFF - nothing fancy [1].
> 
> It was created with gdal_translate -co "COMPRESS=LZW". It's size is 
> 303714237 bytes.
> 
> Process it with gdalwarp -co "COMPRESS=LZW" - it becomes 1443573134 
> bytes big, ie. nearly 5 times bigger. Even about 3 times bigger than the 
> same raster without any compression!
> 
> Worse ratios happen, depending on your data. When can we expect this 
> issue to be fixed?

Maciej,

It is not on my critical path, so I don't anticipate working on it in
the near future.  It may well be challenging for others to address.

Basically, there is no particular timeline for it to be fixed.

You could try and fix it yourself, or contract with someone to fix it
if it is very important to you.

BTW, I assume there is a trac ticket for this problem.  I'd suggest noting
it in emails about the topic.  If it were quoted, I might have contemplated
boosting it's priority.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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