【Android 多媒体应用】使用MediaCodec将摄像头采集的视频编码为h264

本文主要是介绍【Android 多媒体应用】使用MediaCodec将摄像头采集的视频编码为h264，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

转载自：http://www.cnblogs.com/CoderTian/p/6224605.html

MainActivity.java

import android.app.Activity;
import android.graphics.ImageFormat;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.hardware.Camera.PreviewCallback;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;import java.io.IOException;
import java.util.concurrent.ArrayBlockingQueue;public class MainActivity extends Activity  implements SurfaceHolder.Callback,PreviewCallback{private SurfaceView surfaceview;private SurfaceHolder surfaceHolder;private Camera camera;private Parameters parameters;int width = 1280;int height = 720;int framerate = 30;int biterate = 8500*1000;private static int yuvqueuesize = 10;//待解码视频缓冲队列，静态成员！public static ArrayBlockingQueue<byte[]> YUVQueue = new ArrayBlockingQueue<byte[]>(yuvqueuesize);private AvcEncoder avcCodec;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);surfaceview = (SurfaceView)findViewById(R.id.surfaceview);surfaceHolder = surfaceview.getHolder();surfaceHolder.addCallback(this);}@Overridepublic void surfaceCreated(SurfaceHolder holder) {camera = getBackCamera();startcamera(camera);//创建AvEncoder对象avcCodec = new AvcEncoder(width,height,framerate,biterate);//启动编码线程avcCodec.StartEncoderThread();}@Overridepublic void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {}@Overridepublic void surfaceDestroyed(SurfaceHolder holder) {if (null != camera) {camera.setPreviewCallback(null);camera.stopPreview();camera.release();camera = null;avcCodec.StopThread();}}@Overridepublic void onPreviewFrame(byte[] data, android.hardware.Camera camera) {//将当前帧图像保存在队列中putYUVData(data,data.length);}public void putYUVData(byte[] buffer, int length) {if (YUVQueue.size() >= 10) {YUVQueue.poll();}YUVQueue.add(buffer);}private void startcamera(Camera mCamera){if(mCamera != null){try {mCamera.setPreviewCallback(this);mCamera.setDisplayOrientation(90);if(parameters == null){parameters = mCamera.getParameters();}//获取默认的camera配置parameters = mCamera.getParameters();//设置预览格式parameters.setPreviewFormat(ImageFormat.NV21);//设置预览图像分辨率parameters.setPreviewSize(width, height);//配置camera参数mCamera.setParameters(parameters);//将完全初始化的SurfaceHolder传入到setPreviewDisplay(SurfaceHolder)中//没有surface的话，相机不会开启preview预览mCamera.setPreviewDisplay(surfaceHolder);//调用startPreview()用以更新preview的surface，必须要在拍照之前start PreviewmCamera.startPreview();} catch (IOException e) {e.printStackTrace();}}}private Camera getBackCamera() {Camera c = null;try {//获取Camera的实例c = Camera.open(0);} catch (Exception e) {e.printStackTrace();}//获取Camera的实例失败时返回nullreturn c;}}

AvcEncoder.java

import android.media.MediaCodec;
import android.media.MediaCodecInfo;
import android.media.MediaFormat;
import android.os.Environment;import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;import static android.media.MediaCodec.BUFFER_FLAG_CODEC_CONFIG;
import static android.media.MediaCodec.BUFFER_FLAG_KEY_FRAME;public class AvcEncoder
{private final static String TAG = "MeidaCodec";private int TIMEOUT_USEC = 12000;private MediaCodec mediaCodec;int m_width;int m_height;int m_framerate;public byte[] configbyte;public AvcEncoder(int width, int height, int framerate, int bitrate) {m_width  = width;m_height = height;m_framerate = framerate;MediaFormat mediaFormat = MediaFormat.createVideoFormat("video/avc", width, height);mediaFormat.setInteger(MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420SemiPlanar);mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, width*height*5);mediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, 30);mediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 1);try {mediaCodec = MediaCodec.createEncoderByType("video/avc");} catch (IOException e) {e.printStackTrace();}//配置编码器参数mediaCodec.configure(mediaFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);//启动编码器mediaCodec.start();//创建保存编码后数据的文件createfile();}private static String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/test1.h264";private BufferedOutputStream outputStream;private void createfile(){File file = new File(path);if(file.exists()){file.delete();}try {outputStream = new BufferedOutputStream(new FileOutputStream(file));} catch (Exception e){e.printStackTrace();}}private void StopEncoder() {try {mediaCodec.stop();mediaCodec.release();} catch (Exception e){e.printStackTrace();}}public boolean isRuning = false;public void StopThread(){isRuning = false;try {StopEncoder();outputStream.flush();outputStream.close();} catch (IOException e) {e.printStackTrace();}}int count = 0;public void StartEncoderThread(){Thread EncoderThread = new Thread(new Runnable() {@Overridepublic void run() {isRuning = true;byte[] input = null;long pts =  0;long generateIndex = 0;while (isRuning) {//访问MainActivity用来缓冲待解码数据的队列if (MainActivity.YUVQueue.size() >0){//从缓冲队列中取出一帧input = MainActivity.YUVQueue.poll();byte[] yuv420sp = new byte[m_width*m_height*3/2];//把待编码的视频帧转换为YUV420格式NV21ToNV12(input,yuv420sp,m_width,m_height);input = yuv420sp;}if (input != null) {try {long startMs = System.currentTimeMillis();//编码器输入缓冲区ByteBuffer[] inputBuffers = mediaCodec.getInputBuffers();//编码器输出缓冲区ByteBuffer[] outputBuffers = mediaCodec.getOutputBuffers();int inputBufferIndex = mediaCodec.dequeueInputBuffer(-1);if (inputBufferIndex >= 0) {pts = computePresentationTime(generateIndex);ByteBuffer inputBuffer = inputBuffers[inputBufferIndex];inputBuffer.clear();//把转换后的YUV420格式的视频帧放到编码器输入缓冲区中inputBuffer.put(input);mediaCodec.queueInputBuffer(inputBufferIndex, 0, input.length, pts, 0);generateIndex += 1;}MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();int outputBufferIndex = mediaCodec.dequeueOutputBuffer(bufferInfo, TIMEOUT_USEC);while (outputBufferIndex >= 0) {//Log.i("AvcEncoder", "Get H264 Buffer Success! flag = "+bufferInfo.flags+",pts = "+bufferInfo.presentationTimeUs+"");ByteBuffer outputBuffer = outputBuffers[outputBufferIndex];byte[] outData = new byte[bufferInfo.size];outputBuffer.get(outData);if(bufferInfo.flags == BUFFER_FLAG_CODEC_CONFIG){configbyte = new byte[bufferInfo.size];configbyte = outData;}else if(bufferInfo.flags == BUFFER_FLAG_KEY_FRAME){byte[] keyframe = new byte[bufferInfo.size + configbyte.length];System.arraycopy(configbyte, 0, keyframe, 0, configbyte.length);//把编码后的视频帧从编码器输出缓冲区中拷贝出来System.arraycopy(outData, 0, keyframe, configbyte.length, outData.length);outputStream.write(keyframe, 0, keyframe.length);}else{//写到文件中outputStream.write(outData, 0, outData.length);}mediaCodec.releaseOutputBuffer(outputBufferIndex, false);outputBufferIndex = mediaCodec.dequeueOutputBuffer(bufferInfo, TIMEOUT_USEC);}} catch (Throwable t) {t.printStackTrace();}} else {try {Thread.sleep(500);} catch (InterruptedException e) {e.printStackTrace();}}}}});EncoderThread.start();}private void NV21ToNV12(byte[] nv21,byte[] nv12,int width,int height){if(nv21 == null || nv12 == null)return;int framesize = width*height;int i = 0,j = 0;System.arraycopy(nv21, 0, nv12, 0, framesize);for(i = 0; i < framesize; i++){nv12[i] = nv21[i];}for (j = 0; j < framesize/2; j+=2){nv12[framesize + j-1] = nv21[j+framesize];}for (j = 0; j < framesize/2; j+=2){nv12[framesize + j] = nv21[j+framesize-1];}}/*** Generates the presentation time for frame N, in microseconds.*/private long computePresentationTime(long frameIndex) {return 132 + frameIndex * 1000000 / m_framerate;}
}

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent" ><SurfaceView
        android:id="@+id/surfaceview"android:layout_width="match_parent"android:layout_height="match_parent"/></RelativeLayout>

添加权限

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.INTERNET" />