LibTiff Mailing List
TIFF and LibTiff Mailing List Archive
October 2005
Previous Thread
Next Thread
Previous by Thread
Next by Thread
Previous by Date
Next by Date
Contact
The TIFF Mailing List Homepage
This list is run by Frank Warmerdam
Archive maintained by AWare Systems
Thread
2005.10.26 22:06 "Re: checking test images", by Frank Warmerdam
On 10/26/05, ryuki_dono <ryuki_dono@yahoo.de> wrote: > I think so too. In most cases there is no need for accurate data > display. If you want to create a simple preview or thumbnails from tiff > files the loss through downsampling doesn't matter. Ryuki, Well, it does if the image is floating point and the values are between -100 and 3000 and the default scaling assuming inputs in the 0.0 to 1.0 range. In this case default scaling rules will produce a useless image. Nevertheless, I am not adverse to someone knowledgable implementing default rules for more image types in the RGBA interface. I was previously pointing out that I'm not going to do it, because it wouldn't be of much use in my community. I would also stress that the RGBA implementation code is pretty damn confusing and easy to screw up. > I tried to use the default errorhandler and under normal conditions it > would be the best solution. Unfortunately I'm missing JPEG support. You > can look > at the errormessages I get for images like zackthecat.tif. While > TIFFReadRGBAImage reads unsupported TIFF files, recovers from errors and > give back > a NULL, it crashes fatal here. For the moment I stick to the exception > throwing. If there is a fatal crash with zackthecat.tif then perhaps you should be filing a bug report. I just ran "tiff2rgba" on zackthecat.tif and it fails of course because it is old jpeg, but it doesn't crash. So crashing is not the normal behavior. Best regards, -- ---------------------------------------+-------------------------------------- I set the clouds in motion - turn up | Frank Warmerdam, warmerdam@pobox.com light and sound - activate the windows | http://pobox.com/~warmerdam and watch the world go round - Rush | Geospatial Programmer for Rent