AWARE [SYSTEMS]
AWare Systems, , Home TIFF and LibTiff Mailing List Archive

LibTiff Mailing List

TIFF and LibTiff Mailing List Archive
May 2007

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



New Datamatrix section



Valid HTML 4.01!



Thread

2007.05.04 11:51 "TIFFSetField and float values", by <mikk@go2.pl>
2007.05.04 12:18 "Re: TIFFSetField and float values", by Andrey Kiselev
2007.05.04 12:46 "Re: TIFFSetField and float values", by <mikk@go2.pl>
2007.05.04 13:02 "Re: TIFFSetField and float values", by Joris Van Damme
2007.05.04 13:13 "Re: TIFFSetField and float values", by Toby Thain
2007.05.04 13:20 "Re: TIFFSetField and float values", by Joris Van Damme
2007.05.04 21:06 "TIFFSetField and float values", by Mahmoudi Wafa

2007.05.04 13:02 "Re: TIFFSetField and float values", by Joris Van Damme

mikk,

mikk wrote:
> Oh, my, I've found the reason. Digging into the source code I realized
> that TIFFSetField
> gets the parameter from va_arg as double:
> (From tif_dir.c,v 1.72 2006/03/15 12:49:35, line 234:)
> // ...
> case TIFFTAG_XRESOLUTION:
>         td->td_xresolution = (float) va_arg(ap, double);
>         break;
> // ...
>
> When I pass argument of type double, the tag saves the value properly.
> Looks like an error in documentation (TIFFSetField.3tiff.html)?

I would agree... but I suspect other compilers may behave differently. I 
suspect that passing a float, as per documentation, would work for most, but 
passing a double will work for all. I've also tried changing the code you 
quote from tif_dir.c to va_arg(ap,float), but that doesn't work on our 
Borland compilers at all (and likely it will not work on most other 
compilers either, I think). So I'm about to propose to change the 
documention to specify a double parameter as part of the next update.


Best regards,

Joris Van Damme
info@awaresystems.be
http://www.awaresystems.be/
Download your free TIFF tag viewer for windows here:
http://www.awaresystems.be/imaging/tiff/astifftagviewer.html