Thumbnail generators

lib/thumbs.js

@@ -0,0 +1,54 @@
+var exec = require('child_process').exec;
+var im = require('imagemagick');
+var path = require('path');
+
+var imageThumb = function (input, output, format, width, height, callback) {
+  if (typeof height === 'function') {
+    callback = height;
+    height = null;
+  }
+
+  return im.crop({
+    srcPath: input,
+    dstPath: output,
+    width: width,
+    height: height,
+    format: format
+  }, callback);
+}
+
+var videoThumb = function (input, output, format, width, height, callback) {
+  if (typeof height === 'function') {
+    callback = height;
+    height = '?';
+  }
+
+  function escapePath (str) {
+    return '"' + path.normalize(str.replace(/(["\s'$`\\])/g,'\\$1')) + '"';
+  }
+
+  if (output)
+    output = escapePath(output);
+  else
+    output = 'pipe:' + format;
+
+  // Ideally, we'd be doing this via some library, but I'm yet to find one
+  // that seems to allow for buffer output, rather than saving to file.
+
+  var args = [
+    '-loglevel', 0,             // Turn off output
+    '-i', escapePath(input),    // Use input file
+    '-vframes', 1,              // Use only one frame
+    '-ss', '00:00:02',          // Taken from two seconds in
+    '-s', width + 'x' + height, // Thumbnail dimensions
+    '-f', 'image2',             // Set commands file
+    output                      // Output
+  ];
+
+  var cmd = 'ffmpeg ' + args.join(' ');
+
+  return exec(cmd, {encoding: 'binary'}, callback);
+}
+
+module.exports.image = imageThumb;
+module.exports.video = videoThumb;

package.json

@@ -8,6 +8,7 @@
     "bcrypt": "~0.7.5",
     "connect-flash": "~0.1.1",
     "express": "~3.1.0",
+    "imagemagick": "~0.1.3",
     "knox": "~0.8.2",
     "mysql": "~2.0.0-alpha7",
     "nunjucks": "~0.1.8a",