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
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?