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MediaCodec encoder sample
import java.nio.ByteBuffer;
public class AvcEncoder {
private EncodedFrameListener frameListener;
private MediaCodec mediaCodec;
private byte[] sps;
private byte[] pps;
private ParameterSetsListener parameterSetsListener;
public AvcEncoder() {
mediaCodec = MediaCodec.createEncoderByType("video/avc");
MediaFormat mediaFormat = MediaFormat.createVideoFormat("video/avc", 320, 240);
mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, 125000);
mediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, 15);
mediaFormat.setInteger(MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420Planar);
mediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 5);
mediaCodec.configure(mediaFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
public void close() throws IOException {
public void offerEncoder(byte[] input) {
try {
ByteBuffer[] inputBuffers = mediaCodec.getInputBuffers();
ByteBuffer[] outputBuffers = mediaCodec.getOutputBuffers();
int inputBufferIndex = mediaCodec.dequeueInputBuffer(-1);
if (inputBufferIndex >= 0) {
ByteBuffer inputBuffer = inputBuffers[inputBufferIndex];
mediaCodec.queueInputBuffer(inputBufferIndex, 0, input.length, 0, 0);
MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
int outputBufferIndex = mediaCodec.dequeueOutputBuffer(bufferInfo, 0);
while (outputBufferIndex >= 0) {
ByteBuffer outputBuffer = outputBuffers[outputBufferIndex];
byte[] outData = new byte[bufferInfo.size];
if (sps != null && pps != null) {
ByteBuffer frameBuffer = ByteBuffer.wrap(outData);
frameBuffer.putInt(bufferInfo.size - 4);
frameListener.frameReceived(outData, 0, outData.length);
} else {
ByteBuffer spsPpsBuffer = ByteBuffer.wrap(outData);
if (spsPpsBuffer.getInt() == 0x00000001) {
System.out.println("parsing sps/pps");
} else {
System.out.println("something is amiss?");
int ppsIndex = 0;
while(!(spsPpsBuffer.get() == 0x00 && spsPpsBuffer.get() == 0x00 && spsPpsBuffer.get() == 0x00 && spsPpsBuffer.get() == 0x01)) {
ppsIndex = spsPpsBuffer.position();
sps = new byte[ppsIndex - 8];
System.arraycopy(outData, 4, sps, 0, sps.length);
pps = new byte[outData.length - ppsIndex];
System.arraycopy(outData, ppsIndex, pps, 0, pps.length);
if (null != parameterSetsListener) {
parameterSetsListener.avcParametersSetsEstablished(sps, pps);
mediaCodec.releaseOutputBuffer(outputBufferIndex, false);
outputBufferIndex = mediaCodec.dequeueOutputBuffer(bufferInfo, 0);
} catch (Throwable t) {

what is this:
EncodedFrameListener frameListener;
and te
ParameterSetsListener parameterSetsListener?


I amconfused on EncodedFrameListener and ParameterSetsListener, is it the private Listener which is not provided by the Android SDK?


It seems, author means custom class

public class EncodedFrameListener {
    public void frameReceived(byte[] data, int pos, int length) {



Hi npakudin,
This page is in Korean. Can you please give more details about EncodedFrameListener. Thanks in advance.

hpp commented Aug 26, 2013

I found this example very useful, thanks wobbals!

EncodedFrameListener is just a listener for when a new frame has been encoded. In my case I would just open the file being written to and write in the new frame information.

ParameterSetsListener is just a listener that updates some parameters.


Super old thread but I am having bit of an issue. when offering the data I get the following error:
Attempt to invoke virtual method 'java.nio.ByteBuffer[]' on a null object reference

This is the line that produces the error:
ByteBuffer[] inputBuffers = mediaCodec.getInputBuffers();

However, I have checked and recheck...the MediaCodec object is not null. Any assistance is appreciated.

leye0 commented Oct 18, 2015

How is your MediaCodec object created? The part where you are doing MediaCodec.Create(encoder/decoder)By(type/codecName), and after that? Do you configure it? Do you see errors in the log when executing it line by line?


Thanks for the reply, it's verbatim from the above code with a few more try/catch attempts. It seems that the mediaCodec object is not being created, but there are no errors thrown during it's creation, no errors during configuration. Here is the entire file.

I really appreciate the assist.


Can anyone tell me the detail use of this encoder? Actually i can't fully understand it. Do i send the byte data received each call on
new Camera.PreviewCallback() {
public void onPreviewFrame(byte[] data, Camera camera) {
Constants.debugLog(TAG, "data ===" + data.length);
to the encoder each time? or all the byte at a single time? How do i save the file?

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