From 0ed7c1592f0f936477f1797a8d3c009608c72b09 Mon Sep 17 00:00:00 2001
From: Jan Alonzo <jmalonzo@taguchimail.com>
Date: Thu, 11 Dec 2014 08:34:22 +0700
Subject: [PATCH] Expose cwebp's -metadata option

---
 Gruntfile.js  | 5 +++--
 README.md     | 5 +++--
 tasks/webp.js | 8 ++++++++
 3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/Gruntfile.js b/Gruntfile.js
index 594164e..09c97a2 100755
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -42,7 +42,8 @@ module.exports = function(grunt) {
         alphaFilter: 'best',
         alphaCleanup: true,
         noAlpha: false,
-        lossless: false
+        lossless: false,
+        metadata: 'all'
       }
     }
 
@@ -58,4 +59,4 @@ module.exports = function(grunt) {
   // plugin's task(s), then test the result.
   grunt.registerTask('test', ['clean', 'webp']);
 
-};
\ No newline at end of file
+};
diff --git a/README.md b/README.md
index 93b625e..a1e7045 100644
--- a/README.md
+++ b/README.md
@@ -45,7 +45,7 @@ This plugin requires Grunt `~0.4.0`
 * __alphaCleanup (boolean)__ Clean RGB values in transparent area. 
 * __noAlpha (boolean)__ Discard any transparency information. 
 * __lossless (boolean)__  Encode image losslessly.
-
+* __metadata (string)__ Image metadata to copy from input to output
 
 ## Example
 
@@ -84,7 +84,8 @@ module.exports = function(grunt) {
         alphaFilter: 'best',
         alphaCleanup: true,
         noAlpha: false,
-        lossless: false
+        lossless: false,
+        metadata: "all"
       }
     }
 
diff --git a/tasks/webp.js b/tasks/webp.js
index 0452559..98a0f74 100755
--- a/tasks/webp.js
+++ b/tasks/webp.js
@@ -276,6 +276,14 @@ module.exports = function(grunt) {
         args.push(options.quality);
       }
 
+      /**
+       * Image metadata to copy from input to output
+       */
+      if (options.metadata) {
+        args.push('-metadata');
+        args.push(options.metadata);
+      }
+
       /**
        * Outputs the rules that have been matched.
        */