From 207010c76fd054c011e4e418abb817331fee6b88 Mon Sep 17 00:00:00 2001
From: Oliver Vogel <oliver@olivervogel.net>
Date: Tue, 10 Dec 2013 16:52:22 +0100
Subject: [PATCH] added interlace method

---
 src/Intervention/Image/Image.php | 13 +++++++++++++
 tests/ImageTest.php              | 11 +++++++++++
 2 files changed, 24 insertions(+)

diff --git a/src/Intervention/Image/Image.php b/src/Intervention/Image/Image.php
index 007c4f17..faee0006 100644
--- a/src/Intervention/Image/Image.php
+++ b/src/Intervention/Image/Image.php
@@ -1352,6 +1352,19 @@ class Image
         return $this;
     }
 
+    /**
+     * Determine whether an Image should be interlaced
+     *
+     * @param  boolean $interlace
+     * @return Image
+     */
+    public function interlace($interlace = true)
+    {
+        imageinterlace($this->resource, $interlace);
+
+        return $this;
+    }
+
     /**
      * Reset to original image resource
      *
diff --git a/tests/ImageTest.php b/tests/ImageTest.php
index 88541ff6..22fbf51a 100644
--- a/tests/ImageTest.php
+++ b/tests/ImageTest.php
@@ -1389,6 +1389,17 @@ class ImageTest extends PHPUnit_Framework_Testcase
         $this->assertEquals($color2['a'], 1);
     }
 
+    public function testInterlaceImage()
+    {
+        $img = Image::make('public/trim.png');
+        $img->interlace();
+        $contents = $img->encode();
+        $this->assertEquals(( ord($contents[28]) != '0' ), true);
+        $img->interlace(false);
+        $contents = $img->encode();
+        $this->assertEquals(( ord($contents[28]) != '0' ), false);
+    }
+
     public function testSaveImage()
     {
         $save_as = 'public/test2.jpg';