2004.09.02 08:42 "[Tiff] order of writed data in TIFF file", by Poom

2004.09.02 13:52 "Re: [Tiff] order of writed data in TIFF file", by Frank Warmerdam

I used libtiff to create TIFF file.First,I used TIFFSetField to set a value of tag and then write image data to file with command "TIFFWriteScanline" .At last close file with "TIFFClose".

When I check my TIFF file ,I found that IFD part is wrote under image data ,but when I look at TIFF file from photoshop,IFD is come after IFH.

I suspect why my TIFF file has been come like this. If anyone know about this result,suggest me please.

Poom,

I don't know what an IFH is, but I suspect you are wondering whether the directory (IFD) information should be written before or after the image data. Is that right? The answer is that the TIFF format has no requirement on this. In normal operation with libtiff the directory is written on TIFFClose() and would be written after the image data. Some other applications write the directory before the imagery. Either is fine.

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