First stab at images and git-annex.

[homepage.git] / lib / imgresize.rb

diff --git a/lib/imgresize.rb b/lib/imgresize.rb
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+# Nick's web site: imgresize filter.  Helper for resizing images during site
+# compilations for thumbnails, etc.
+#
+# Copyright © 2016, 2020 Nick Bowler
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+class ImgResize < Nanoc::Filter
+    identifier :imgresize
+    type       :binary
+
+    def run(filename, params = {})
+        w = if params[:width] then params[:width].to_i end
+        h = if params[:height] then params[:height].to_i end
+        scale = [w, h && "x", h].join
+
+        args = ["-scale", scale, filename]
+        case filename
+        when /\.jpg$/
+            args << "-quality" << "85"
+        end
+        args << output_filename
+
+        system('gm', 'convert', *args)
+    end
+end