diff --git a/src/main/java/org/forkalsrud/album/video/FlvMetadata.java b/src/main/java/org/forkalsrud/album/video/FlvMetadata.java
index 95b68e5..2caeca5 100644
--- a/src/main/java/org/forkalsrud/album/video/FlvMetadata.java
+++ b/src/main/java/org/forkalsrud/album/video/FlvMetadata.java
@@ -113,7 +113,7 @@ public class FlvMetadata {
 
             writeFlvValueArray(out, "filepositions", value.size());
             for (Keyframe f : value) {
-                offset.set(f.getFileOffset(0));
+                offset.set(f.getFileOffset());
                 offset.write(out);
             }
             writeFlvValueArray(out, "times", value.size());
@@ -211,7 +211,16 @@ public class FlvMetadata {
         attrs.add(new KeyframesAttr("keyframes", keyframes));
     }
 
-    private int length = 0;
+
+    private int length() {
+        int i = 0;
+        for (Attr a : attrs) {
+            if (a.isPresent()) {
+                i++;
+            }
+        }
+        return i;
+    }
 
     public void addVideoFrame(int filePos, int timestamp, boolean isKeyframe) {
 
@@ -246,7 +255,7 @@ public class FlvMetadata {
 
         // ScriptDataObject
         out.write(2);
-        writeFlvEcmaArray(out, "onMetaData", length);
+        writeFlvEcmaArray(out, "onMetaData", length());
         for (Attr a : attrs) {
             if (a.isPresent()) {
                 a.write(out);
@@ -353,18 +362,11 @@ public class FlvMetadata {
             this.timestamp = timestamp;
         }
 
-        public int getFileOffset(int delta) {
-            return fileOffset + delta;
-        }
-        public void setFileOffset(int fileOffset) {
-            this.fileOffset = fileOffset;
+        public int getFileOffset() {
+            return fileOffset;
         }
         public int getTimestamp() {
             return timestamp;
         }
-        public void setTimestamp(int timestamp) {
-            this.timestamp = timestamp;
-        }
-
     }
 }