mm2/Little-CMS — Issue #2: Using lcms2 in Poppler or Ghostscript slows down rendering performance
Author: tillkamppeter
Created: 2012-01-23 09:26:26+00:00
State: open

For Ubuntu Precise (12.04) we want to migrate completely from the old liblcms1 to liblcms2, as the new library is maintained upstream:

https://bugs.launchpad.net/ubuntu/+source/lcms/+bug/885324

Unfortunately there is a regression in liblcm2. Most files get rendered slightly slower (5-10%) when Poppler is linked with liblcms2 instead of liblcms1 (for Ghostscript I have no test results).

But most important is that some files render significantly slower. An example is altona_technical_1v2_x3.pdf from http://www.eci.org/doku.php?id=es:downloads. Simply run it through "pdftops" (convert to PostScript with Poppler) or "gs" (screen-display with Ghostscript) on Ubuntu Onneiric (11.10, using liblcms1) and Ubuntu Precise (12.04, using liblcms2) and you see that the rendering is between 5 and 10 times slower with liblcms2. See also comments #16, #37 and #38 on

https://bugs.launchpad.net/ubuntu/+source/lcms/+bug/885324

and

http://www.mail-archive.com/poppler@lists.freedesktop.org/msg06258.html