LibTiff Mailing List

TIFF and LibTiff Mailing List Archive
July 2002

Previous Thread
Next Thread

Previous by Thread
Next by Thread

Previous by Date
Next by Date

The TIFF Mailing List Homepage
This list is run by Frank Warmerdam
Archive maintained by AWare Systems

Thread

2002.07.25 00:32 "How to detect a tiff file is a fax that has horizontal ratio of 2:1?", by Hiu Sing Ngai

2002.07.25 07:51 "Re: How to detect a tiff file is a fax that has horizontal ratio of 2:1?", by Frank D Cringle

2002.07.25 00:32 "How to detect a tiff file is a fax that has horizontal ratio of 2:1?", by Hiu Sing Ngai

Hello,

I'm trying to decode a tiff file created by eFax and other fax provider.
I noticed that the image horizontal ratio is 2:1 of the original.  I
found this on the web memtions about decoding a tiff-fax file
http://www.libpng.org/pub/png/src/tiff2png-0.81c.README
The problem is that the tiff2png program has to input a -faxpact in
order to decode the tiff file in the right ratio.  In what way I know if
a 1 bit tiff has a horizontal ratio of 2:1?  Also, how to I handle the
decompression?  For example, if I detected the image width is 1000 and
height 1000.  Should I set the width to 500 or increase the height to
2000?

Thanks!