[KinesisVideo] Remove trailing zeros before putting frame into SDK (#971)

Author: zhiyua-git

aws-android-sdk-kinesisvideo/src/androidTest/java/com/amazonaws/services/kinesisvideo/KinesisVideoFrameTest.java

@@ -0,0 +1,28 @@
+package com.amazonaws.services.kinesisvideo;
+
+import com.amazonaws.kinesisvideo.producer.KinesisVideoFrame;
+
+import org.junit.Test;
+
+import java.nio.ByteBuffer;
+
+import android.support.test.runner.AndroidJUnit4;
+
+import static com.amazonaws.kinesisvideo.producer.FrameFlags.FRAME_FLAG_NONE;
+import static junit.framework.Assert.assertEquals;
+
+@RunWith(AndroidJUnit4.class)
+public class KinesisVideoFrameTest {
+    @Test
+    public void testTrailingZeroRemoved() {
+        byte[] rawData = new byte[] {1, 2, 3, 0, 0, 0, 0, 0};
+        KinesisVideoFrame frame = new KinesisVideoFrame(0, FRAME_FLAG_NONE, 0,
+                0, 1, ByteBuffer.wrap(rawData));
+        assertEquals(3, frame.getSize());
+        byte[] actualDataPassed = new byte[frame.getSize()];
+        frame.getData().get(actualDataPassed);
+        for (int i = 0; i < actualDataPassed.length; i++) {
+            assertEquals(rawData[i], actualDataPassed[i]);
+        }
+    }
+}

aws-android-sdk-kinesisvideo/src/main/java/com/amazonaws/kinesisvideo/producer/KinesisVideoFrame.java

@@ -69,6 +69,9 @@ public KinesisVideoFrame(int index, int flags, long decodingTs, long presentatio
         mPresentationTs = presentationTs;
         mDuration = duration;
         mData = requireNonNull(data);
+        // In some devices encoder would generate frames with more than 3 trailing zeros
+        // which is not allowed by AnnexB specification
+        removeTrailingZeros();
     }
 
     public int getIndex() {
@@ -116,4 +119,13 @@ public ByteBuffer getData() {
                 .append(", mPresentationTs=").append(mPresentationTs).append(", mDuration=").append(mDuration)
                 .append(", mData=").append(mData).append("}").toString();
     }
+
+    private void removeTrailingZeros() {
+        for (int index = mData.limit() - 1; index > mData.position(); index--) {
+            if (mData.get(index) != 0) {
+                mData.limit(index + 1);
+                break;
+            }
+        }
+    }
 }