[SOLVED] Is there a trick to get webcollage working on Xscreensaver?

ricky_cardo · 03-15-2010, 01:39 AM

While I will not dispute this is not for everyone, I was wondering is there a trick to get webcollage working in Slack 13?

It works from the command prompt with something like this:
/usr/libexec/xscreensaver/webcollage -vvv -size '800x600' -imagemap crazy

Just wondering why the Xscreensaver portion seems to be defunct.

GazL · 03-15-2010, 06:16 AM

If you run it normally you see messages

Code:

xscreensaver-getimage: reason: Couldn't recognize the image file format for file '/tmp/webcollage-b66c23db'

Have a look at this http://bugs.gentoo.org/show_bug.cgi?id=261332
Posts 19 and 23 are the significant ones.

Alternatively, if you don't want to modify the freedesktop.org mime types, my patch below seems to work. (on 64-current anyway)

webcollage.patch:

Code:

#  Patch for webcollage perl script
#
#  Fixes xscreensaver issue:
#   "xscreensaver-getimage: reason: Couldn't recognize the image file format"
#
#  Without the .ppm extension, gtk+/gdk doesn't recognise the file as a .ppm 
#  as the freedesktop.org mime types expect a '#' at offset 3.
#
#  Apply with:
#    cd /usr/libexec/xscreensaver
#    patch < this_file.patch

--- webcollage.old      2010-03-15 11:35:01.846492572 +0000
+++ webcollage  2010-03-15 11:33:00.886492477 +0000
@@ -2709,13 +2709,13 @@
 #
 ##############################################################################
 
-my $image_ppm   = sprintf ("%s/webcollage-%08x",
+my $image_ppm   = sprintf ("%s/webcollage-%08x.ppm",
                            ($ENV{TMPDIR} ? $ENV{TMPDIR} : "/tmp"),
                            rand(0xFFFFFFFF));
-my $image_tmp1  = sprintf ("%s/webcollage-1-%08x",
+my $image_tmp1  = sprintf ("%s/webcollage-1-%08x.ppm",
                            ($ENV{TMPDIR} ? $ENV{TMPDIR} : "/tmp"),
                            rand(0xFFFFFFFF));
-my $image_tmp2  = sprintf ("%s/webcollage-2-%08x",
+my $image_tmp2  = sprintf ("%s/webcollage-2-%08x.ppm",
                            ($ENV{TMPDIR} ? $ENV{TMPDIR} : "/tmp"),
                            rand(0xFFFFFFFF));

volkerdi · 07-19-2010, 01:06 PM

From what I've heard about Webcollage, I'm not sure you'd want it to be working by default...

GazL · 07-20-2010, 03:53 AM

Quote:

Originally Posted by volkerdi

From what I've heard about Webcollage, I'm not sure you'd want it to be working by default...

Yep, we had a good discussion on here a few years back about its dangers. And at that point I was in favour of removing it entirely.

However, its saving grace is that it can be run against images on local directories instead of images pulled randomly from the web, so it does have safer uses too.

My view is that if you're going to ship it, it might as well be a working version. There's really not much point shipping a broken one.

Not that I use it. I like the 'lockward' module.

.oOZe. · 11-15-2010, 06:38 PM

Thanks for the patch! This issue started for me after upgrading from FC13 to FC14.

.oOZe. · 01-20-2011, 02:03 PM

So I ran into the same issue with vidwhacker which uses some of the same functions to generate images as webcollage but it turns out the culprit is actually the shared-mime-info package: http://bugs.gentoo.org/show_bug.cgi?id=261332

It seems that as of 0.51 someone added

Code:

<match value="#" type="string" offset="3"/>

to each image/x-portable-* entry in the file freedesktop.org.xml found in (/usr/share/mime/packages).

After I commented out those lines and ran

Code:

update-mime-database /usr/share/mime

and then reverted the changes previously made to webcollage and vidwhacker they both generate images without errors.

Hope that helps somebody.