dither stuff

1 files changed, 15 insertions, 0 deletions

diff --git a/gif-encode/util.js b/gif-encode/util.js
new file mode 100644
index 0000000..92d8129
--- /dev/null
+++ b/gif-encode/util.js
@@ -0,0 +1,15 @@
+function shuffle(a){
+	var aa = new Array(a.length);
+	aa[0] = a[0];
+
+	for (var i = 1; i < a.length; i++) {
+		var j = Math.floor( Math.random() * i );
+		aa[i] = aa[j];
+		aa[j] = a[i];
+	}
+	return aa;
+}
+function sample(a, n) {
+	var aa = shuffle(a);
+	return aa.slice(0,n);
+}