Strictly speaking, TIFF files which are to be transmitted by fax need to conform to the TIFF-F specification. However, the Brooktrout software is able to tolerate certain deviations from this standard.
If you are having problems faxing a file and suspect there may be a problem with its format, you can use the tiffdump utility to display the contents of a TIFF file. It displays each of the image file directory entries. To obtain a copy of the tiffdump utility you will need to contact Brooktrout, Inc. 250 First Avenue, Needham, MA; 02494-2814; Telephone: +1 781 449 4100/Fax: +1 781 449 9009 or via their Web site (http://www.brooktrout.com).
tiffdump [-d] <tiff_filename>