From b161ed9f124a63eb248b5768b18902216e88d52d Mon Sep 17 00:00:00 2001
From: Yoshihiro Yamazaki <yoya@awm.jp>
Date: Sat, 20 May 2017 13:25:10 +0900
Subject: [PATCH] fix getCanvasContrast: wrong calc for imagedata offset.

---
 spectrum.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/spectrum.js b/spectrum.js
index 3628d81..11764fc 100644
--- a/spectrum.js
+++ b/spectrum.js
@@ -302,7 +302,7 @@ function getCanvasContrast(canvas) {
 	var r = data[i++]
 	var g = data[i++];
 	var b = data[i++];
-	// a ; i++;
+	i++; // a;
 	if (r < minRed) {
 	    minRed = r;
 	} else if (maxRed < r) {