|TIFF and LibTiff Mailing List Archive|
LibTiff Mailing List
2010.08.23 04:54 "Re: tiff2ps page sizing options", by Lee Howard
Richard Nolde wrote: > I'm revisiting tiff2ps to fix a bug with images that have no > resolution unit tag but do have x and y resolutions. That fix seems to > be only a line or two but while I'm back in the code, I'm trying to > clean up a few things in my patches so they can be resubmitted once > more for inclusion in at least some version of libtiff. The current > CVS version has some of my work from 2005 that allows for additional > rotations of 90 and 270 degrees and page chopping by width as well as > height. However, there are known bugs in it that were fixed in > subsequent patches that never got applied in CVS. I'm trying to > simplify the old code and my patches before making any new > submissions. There are also errors in the current man page that I can > address. I'll be happy to review your work when you're done. > I have some questions about how tiff2ps worked originally and/or > should work when multiple options are specified. In particular, there > isn't a clear definition of how the -H, -W, -h -w flags interact when > they are combined. I think that -h and -w define the size of the page > on which the image is presented whereas -H and -W define viewports > into the image that will be output. In other words, -H or -W could be > used to specify that only a portion of the image be displayed on a > given output page, with additional pages created to handle the > overflow. To me, this implies that -H can never be larger than -h, -W > can never be larger than -w. I'm not an authority as I didn't author the -H/-W/-h/-w options, and I don't use those features, but the way that I read the man page documentation (which was written by the options author, I suspect) it appears that -h and -w refer to the printed area of the image. They define the page size. In other words, I may want to resize the image to only be 4x5" area on the page, and I'd do this with the -h and -w options without the use of the -H and -W options. The -H and -W options appear to be ways to print the image on multiple pages without resizing if the image does not fit within the page boundaries defined by -h and -w. Correct, my reading is that -H is never larger than -h and -W is never larger than -w. > If -h and -w are specified alone, the entire image is scaled to fit > on that size output media. If -H is also specified, the image is > scaled to the -w value (or native width if no -w is specified) > horizontally and the result clipped to -H in each page that is > required. If -W is specified with -h and -w, the image is scaled to > the -h value (or native height if no -h is specified), and the result > clipped to -W in each page that is required. Yes/No? This sounds correct to me. > If -H or -W are specified without -h and -w, I assume no scaling > should take place, only clipping and generation of multiple pages as > needed. This also sounds correct. Thanks, Lee.