Originally reported by: htl10@users.sourceforge.net Hi, We are developing an IJS plugin for the Epson EPL-5x00L GDI printers (http://sourceforge.net/projects/epsonepl/). We are a relatively new project and the problem was first reported by a test user about 2 weeks ago, and just been verified by me; The problem is as follows: the GDI printer is a B/W laser printer, so we are driving the IJS plugin with these switches "-sProcessColorModel=DeviceGray -dBitsPerSample=1" with ghostscript 7.04 which I did most of the development, gs 7.04 sends 1 for white and 0 for black, which is fine. However, after I upgrade to 8.0, the plugin seems to be doing something else totally (downgrading right away give me the older behaviour). black and white are both sent as zero, while some blue (0,0,255) letters on a page is rastered and rendered partly as 1. I suspect that the change of behaviour is due to the change in ghostscript around v7.30 , from the introduction of DeviceN colour scheme. Is this a genuine bug of ghostscript 8.0 or a deliberate change of bahavior (e.g. we need some new switches to get the old behavior)?
Comment originally by htl10@users.sourceforge.net Logged In: YES user_id=506848 Just to provide more info. The problem was first observed with v0.1 of epsoneplijs, and again with v0.2 (we only had two release so far). Both have a "ps2epl" script which works somewhat similarly to ps2pdf, and a one-page "epl_test.ps" file for testing purposes. Note that the generated *.epl is not the same between v0.1 and v0.2 so you can't compare v0.1 to v0.2, but the generated *.epl using gs 7.04 should be the same as using gs 8.0 and it is not (with the described difference as far as I can tell, white/black being 0, blue being partly 1). When the problem was first reported, because our epl_test.ps is B/W, the user reported that it came out all black, and I only found the curious behavior with blue when I did it with a pdf file which happened to have some hypertext links in blue but otherwise was black letter on white page. The whole page comes out as black except the hypertext links. The ps2epl contains the gs options, etc. You might have to be a be careful about $PATH, etc.
Comment originally by htl10@users.sourceforge.net Logged In: YES user_id=506848 More info; I built every version of ghostscript between 7.04 and 8.00 7.04, 7.05, 7.21, 7.22 - okay 7.32, 7.33, 8.00 - broken. 7.20 - defaults not to build ijs client, so didn't test; 7.30 - Unrecoverable error: rangecheck in .putdeviceprops 7.31 - Segmentation fault
This one-liner change fixes the problem. Since I haven't heard from the Ghostscript people for almost half a year, I have started distributing patched version of ghostscript 8.0 at user's request, at http://sourceforge.net/project/showfiles.php?group_id=69547&release_id=173560 Please let me know if you would like the distribution to stop. ============================================================ --- src/gdevijs.c~ 2002-10-30 12:35:11.000000000 +0000 +++ src/gdevijs.c 2003-03-30 05:42:48.000000000 +0100 @@ -1075,6 +1075,7 @@ } maxvalue = (1 << bpc) - 1; + dci.max_components = components; dci.num_components = components; dci.depth = bpc * components; dci.max_gray = maxvalue; ==============================================================
Fix committed: http://www.ghostscript.com/pipermail/gs-cvs/2004-March/004317.html