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Android视频处理之动态时间水印效果

最近的项目中遇到一个非常头痛的需求,在Android端录制视频的时候动态添加像监控画面一样的精确到秒的时间信息,关键是,并不是说只在播放器的界面显示时间就可以了,而是录制到视频里面去,这个MP4在电脑上播放也能看到每个画面的时间。
最后想到的办法是在录制完成以后去处理这个视频。

期间参考了很多资料,比较有用的大概是ffmpeg和比较新的Api mediaCodec系列了。介于ffmpeg都是C实现,和一大堆NDK相关,本人不是太懂,就重点关注了MediaCodec系列。

参考逻辑流程图一目了然的这篇博文

MediaCodec进行编解码的大体逻辑是这样的(转载):

主要函数的调用逻辑如下:

MediaExtractor,MediaCodec,MediaMuxer这三个Api已经可以很多多媒体处理工作了,比如用MediaExtractor+MediaMuxer就可以做音视频剪辑,MediaCodec+MediaMuxer就可以做自定义的录像机,一起用就可以做特效编辑,滤镜之类的了。

添加时间水印效果

关键在于取到的数据帧,是YUV格式的,根据拍摄时选取的不同还不一样,我用到的NV21格式,也就是YUV420sp,拿到NV21格式的帧以后,转成RGB渲染,然后又转回NV21交给encoder,看起来好笨重,也非常地耗时,但我还没找到更好的办法。

 private Bitmap first;

 private void handleFrameData(byte[] data, MediaCodec.BufferInfo info) {
 //YUV420sp转RGB数据 5-60ms
 ByteArrayOutputStream out = new ByteArrayOutputStream();
 YuvImage yuvImage = new YuvImage(data, ImageFormat.NV21, srcWidth, srcHeight, null);
 yuvImage.compressToJpeg(new Rect(0, 0, srcWidth, srcHeight), 100, out);
 byte[] imageBytes = out.toByteArray();

 //旋转图像,顺便解决电脑上播放被旋转90度的问题 20-50ms
 Bitmap image = BitmapFactory.decodeByteArray(imageBytes, 0, imageBytes.length);
 Bitmap bitmap = rotaingImageView(videoRotation, image);
 image.recycle();

 //渲染文字 0-1ms
 Canvas canvas = new Canvas(bitmap);
 canvas.drawText(videoTimeFormat.format(videoFirstTime + info.presentationTimeUs / 1000), 10, 30, paint);

 //预览处理帧 0-5ms
 first = bitmap;
 handler.sendEmptyMessage((int) (info.presentationTimeUs / 1000));

 synchronized (MediaCodec.class) {//记得加锁
 timeDataContainer.add(new Frame(info, bitmap));
 }
 }
 /*
 * 旋转图片
 * @param angle
 * @param bitmap
 * @return Bitmap
 */
 public Bitmap rotaingImageView(int angle, Bitmap bitmap) {
 //旋转图片 动作
 Matrix matrix = new Matrix();
 matrix.postRotate(angle);
 // 创建新的图片
 return Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
 }

然后是转回NV21

/**
 * 获取夹了时间戳的的数据
 *
 * @return
 */
 private Frame getFrameData() {
 synchronized (MediaCodec.class) {//记得加锁

 if (timeDataContainer.isEmpty()) {
 return null;
 }

 //从队列中获取数据
 Frame frame = timeDataContainer.remove(0);////取出后将此数据remove掉 既能保证PCM数据块的取出顺序 又能及时释放内存

 //转回YUV420sp 120-160ms
 frame.data = getNV21(dstWidth, dstHeight, frame.bitmap);

 return frame;
 }
 }
 public static byte[] getNV21(int width, int height, Bitmap scaled) {

 int[] argb = new int[width * height];

 scaled.getPixels(argb, 0, width, 0, 0, width, height);

 byte[] yuv = new byte[width * height * 3 / 2];

 encodeYUV420SP(yuv, argb, width, height);

 scaled.recycle();

 return yuv;
 }


 /**
 * 将bitmap里得到的argb数据转成yuv420sp格式
 * 这个yuv420sp数据就可以直接传给MediaCodec,通过AvcEncoder间接进行编码
 *
 * @param yuv420sp 用来存放yuv420sp数据
 * @param argb 传入argb数据
 * @param width 图片width
 * @param height 图片height
 */
 public static void encodeYUV420SP(byte[] yuv420sp, int[] argb, int width, int height) {
 final int frameSize = width * height;

 int yIndex = 0;
 int uvIndex = frameSize;

 int a, R, G, B, Y, U, V;
 int index = 0;
 for (int j = 0; j < height; j++) {
 for (int i = 0; i < width; i++) {

// a = (argb[index] & 0xff000000) >> 24; // a is not used obviously
 R = (argb[index] & 0xff0000) >> 16;
 G = (argb[index] & 0xff00) >> 8;
 B = (argb[index] & 0xff) >> 0;

 // well known RGB to YUV algorithm
 Y = ((66 * R + 129 * G + 25 * B + 128) >> 8) + 16;
 U = ((-38 * R - 74 * G + 112 * B + 128) >> 8) + 128;
 V = ((112 * R - 94 * G - 18 * B + 128) >> 8) + 128;

 // NV21 has a plane of Y and interleaved planes of VU each sampled by a factor of 2
 // meaning for every 4 Y pixels there are 1 V and 1 U. Note the sampling is every other
 // pixel AND every other scanline.
 yuv420sp[yIndex++] = (byte) ((Y < 0) ? 0 : ((Y > 255) ? 255 : Y));
 if (j % 2 == 0 && index % 2 == 0) {
 yuv420sp[uvIndex++] = (byte) ((V < 0) ? 0 : ((V > 255) ? 255 : V));
 yuv420sp[uvIndex++] = (byte) ((U < 0) ? 0 : ((U > 255) ? 255 : U));
 }

 index++;
 }
 }
 }

看到上面的代码执行耗时,根本不可能实时录制时处理,就算后台服务处理,3秒钟的720*480视频得花费约20秒..

解码与编码的地方也有很多,比如编码器在某些手机不支持颜色格式,为了适配更多机型,颜色格式的设置以后需要更换。

 /**
 * 初始化编码器
 */

 private void initMediaEncode(String mime) {
 try {
 MediaFormat format = MediaFormat.createVideoFormat(MediaFormat.MIMETYPE_VIDEO_AVC, dstWidth, dstHeight);
 format.setInteger(MediaFormat.KEY_BIT_RATE, 1024 * 512);
 format.setInteger(MediaFormat.KEY_FRAME_RATE, 27);
 format.setInteger(MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420Flexible);
// format.setInteger(MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420Planar);
 format.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 1);

 mediaEncode = MediaCodec.createEncoderByType(MediaFormat.MIMETYPE_VIDEO_AVC);
 mediaEncode.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
 } catch (IOException e) {
 e.printStackTrace();
 }

 if (mediaEncode == null) {
 JLog.e(tag, "create mediaEncode failed");
 return;
 }
 mediaEncode.start();

 }

补充:匹配大部分手机的颜色模式应该是MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420SemiPlanar=21,这个颜色格式是在decode解码首buffer的时候得到的,但这个format居然没有码率,关键帧间隔,以及FPS等,这些只能根据自己情况设
为什么我之前用了YUV420Flexible,android源码里面说的YUV420SemiPlanner弃用

@deprecated Use {@link #COLOR_FormatYUV420Flexible}。
public static final int COLOR_FormatYUV420SemiPlanar        = 21;

不过现在可以从源文件首buffer里面解码读取出来

 case MediaCodec.INFO_OUTPUT_FORMAT_CHANGED:
 MediaFormat format = mediaDecode.getOutputFormat();
 Log.d(tag, "New format " + format);
 if (format != null && format.containsKey(MediaFormat.KEY_COLOR_FORMAT)) {
 videoColorFormat = format.getInteger(MediaFormat.KEY_COLOR_FORMAT);
 Log.d(tag, "decode extract get videoColorFormat =" + videoColorFormat);//解码得到视频颜色格式
 }
 initMediaEncode(videoColorFormat);//根据颜色格式初始化编码器
 break;

源码:

import android.annotation.TargetApi;
import android.app.Service;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ImageFormat;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.YuvImage;
import android.media.MediaCodec;
import android.media.MediaCodecInfo;
import android.media.MediaExtractor;
import android.media.MediaFormat;
import android.media.MediaMetadataRetriever;
import android.media.MediaMuxer;
import android.os.Binder;
import android.os.Build;
import android.os.IBinder;
import android.os.Message;
import android.support.annotation.Nullable;
import android.widget.Toast;


import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.lang.ref.WeakReference;
import java.nio.ByteBuffer;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.List;

/**

 * Created by user on 2016/8/13.

 */
@TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR2)
public class TestCodecService extends Service {

 private MediaExtractor extractor;
 private MediaMuxer muxer;
 private final static String tag = "px";
 private final String TAG = this.getClass().getSimpleName();
 private MediaFormat format;

 private int videoMaxInputSize = 0, videoRotation = 0;
 private long videoDuration;

 private boolean decodeOver = false, encoding = false, mCancel, mDelete;

 //视频流在数据流中的序号


 private int videoTrackIndex = -1;

 private MediaCodec mediaDecode, mediaEncode;
 private ByteBuffer[] decodeInputBuffers, decodeOutputBuffers;

 private ArrayList<Frame> timeDataContainer;//数据块容器


 private MediaCodec.BufferInfo decodeBufferInfo;


 private int srcWidth, srcHeight, dstWidth, dstHeight;

 private SimpleDateFormat videoTimeFormat;

 private int mProgress, mMax;
 private VideoCodecDao codecDao;

 //绘制时间戳的画笔


 private Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);

 @Override
 public void onCreate() {
 super.onCreate();
 JLog.d(TAG, "onCreate");
 //视频时间戳显示格式


 videoTimeFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");

 timeDataContainer = new ArrayList<>();

 //初始化画笔工具


 paint.setColor(Color.WHITE);
 paint.setTextSize(20);
 codecDao = VideoCodecDao.getInstance(JingRuiApp.getJRApplicationContext());

 }

 @Override
 public void onDestroy() {
 super.onDestroy();
 JLog.d(TAG, "onDestroy");
 decodeOver = true;
 encoding = false;
 }

 private void init(String srcPath, String dstpath) {
 MediaMetadataRetriever mmr = new MediaMetadataRetriever();
 mmr.setDataSource(srcPath);
 try {
 srcWidth = Integer.parseInt(mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_VIDEO_WIDTH));
 srcHeight = Integer.parseInt(mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_VIDEO_HEIGHT));
 } catch (IllegalArgumentException e) {
 e.printStackTrace();
 } catch (IllegalStateException e) {
 e.printStackTrace();
 }

 try {
 extractor = new MediaExtractor();
 extractor.setDataSource(srcPath);

 String mime = null;
 for (int i = 0; i < extractor.getTrackCount(); i++) {
 //获取码流的详细格式/配置信息


 MediaFormat format = extractor.getTrackFormat(i);
 mime = format.getString(MediaFormat.KEY_MIME);
 if (mime.startsWith("video/")) {
  videoTrackIndex = i;
  this.format = format;
 } else if (mime.startsWith("audio/")) {
  continue;
 } else {
  continue;
 }
 }


 extractor.selectTrack(videoTrackIndex); //选择读取视频数据


 //创建合成器


 srcWidth = format.getInteger(MediaFormat.KEY_WIDTH);
 dstHeight = format.getInteger(MediaFormat.KEY_HEIGHT);
 videoMaxInputSize = format.getInteger(MediaFormat.KEY_MAX_INPUT_SIZE);
 videoDuration = format.getLong(MediaFormat.KEY_DURATION);
 //videoRotation = format.getInteger(MediaFormat.KEY_ROTATION);


 videoRotation = 90;//低版本不支持获取旋转,手动写入了


 if (videoRotation == 90) {
 dstWidth = srcHeight;
 dstHeight = srcWidth;
 } else if (videoRotation == 0) {
 dstWidth = srcWidth;
 dstHeight = srcHeight;
 }
 mMax = (int) (videoDuration / 1000);
 //int bit = this.format.getInteger(MediaFormat.KEY_BIT_RATE);

 JLog.d(tag, "videoWidth=" + srcWidth + ",videoHeight=" + srcHeight + ",videoMaxInputSize=" + videoMaxInputSize + ",videoDuration=" + videoDuration + ",videoRotation=" + videoRotation);

 //写入文件的合成器

 muxer = new MediaMuxer(dstpath, MediaMuxer.OutputFormat.MUXER_OUTPUT_MPEG_4);
 //向合成器添加视频轨


 //videoTrackIndex = muxer.addTrack(format);

 MediaCodec.BufferInfo videoInfo = new MediaCodec.BufferInfo();
 videoInfo.presentationTimeUs = 0;

 initMediaDecode(mime);
 initMediaEncode(mime);

 } catch (IOException e) {
 e.printStackTrace();
 }
 }

 //抽出每一帧

 @TargetApi(Build.VERSION_CODES.LOLLIPOP)
 private void extract() {
 int inputIndex = mediaDecode.dequeueInputBuffer(-1);//获取可用的inputBuffer -1代表一直等待,0表示不等待 建议-1,避免丢帧

 if (inputIndex < 0) {
 JLog.d("px", "=========== code over =======");
 return;
 }

 ByteBuffer inputBuffer = decodeInputBuffers[inputIndex];//拿到inputBuffer

 inputBuffer.clear();

 int length = extractor.readSampleData(inputBuffer, 0); //读取一帧数据,放到解码队列

 if (length < 0) {
 JLog.d("px", "extract Over");
 decodeOver = true;
 return;
 } else {
 //获取时间戳


 long presentationTimeUs = extractor.getSampleTime();

 MediaCodec.BufferInfo videoInfo = new MediaCodec.BufferInfo();
 videoInfo.offset = 0;
 videoInfo.size = length;
 //获取帧类型,只能识别是否为I帧


 videoInfo.flags = extractor.getSampleFlags();
 videoInfo.presentationTimeUs = extractor.getSampleTime();

 //解码视频


 decode(videoInfo, inputIndex);
 extractor.advance(); //移动到下一帧

 }

 }


 private void handleFrameData(byte[] data, MediaCodec.BufferInfo info) {
 //YUV420sp转RGB数据 5-60ms


 ByteArrayOutputStream out = new ByteArrayOutputStream();
 YuvImage yuvImage = new YuvImage(data, ImageFormat.NV21, srcWidth, srcHeight, null);
 yuvImage.compressToJpeg(new Rect(0, 0, srcWidth, srcHeight), 100, out);
 byte[] imageBytes = out.toByteArray();

 //旋转图像 20-50ms


 Bitmap image = BitmapFactory.decodeByteArray(imageBytes, 0, imageBytes.length);
 Bitmap bitmap = rotaingImageView(videoRotation, image);
 image.recycle();

 //渲染文字 0-1ms


 Canvas canvas = new Canvas(bitmap);
 canvas.drawText(videoTimeFormat.format(mVideo.videoCreateTime + info.presentationTimeUs / 1000), 10, 30, paint);

 //通知进度 0-5ms


 mProgress = (int) (info.presentationTimeUs / 1000);
 if (mListener != null) {
 mListener.onProgress(mProgress, mMax);
 }

 synchronized (MediaCodec.class) {//记得加锁

 timeDataContainer.add(new Frame(info, bitmap));
 }
 }


 public static byte[] getNV21(int width, int height, Bitmap scaled) {

 int[] argb = new int[width * height];

 scaled.getPixels(argb, 0, width, 0, 0, width, height);

 byte[] yuv = new byte[width * height * 3 / 2];

 encodeYUV420SP(yuv, argb, width, height);

 scaled.recycle();

 return yuv;
 }


 /**

 * 将bitmap里得到的argb数据转成yuv420sp格式

 * 这个yuv420sp数据就可以直接传给MediaCodec,通过AvcEncoder间接进行编码

 *

 * @param yuv420sp 用来存放yuv420sp数据

 * @param argb 传入argb数据

 * @param width 图片width

 * @param height 图片height

 */
 public static void encodeYUV420SP(byte[] yuv420sp, int[] argb, int width, int height) {
 final int frameSize = width * height;

 int yIndex = 0;
 int uvIndex = frameSize;

 int a, R, G, B, Y, U, V;
 int index = 0;
 for (int j = 0; j < height; j++) {
 for (int i = 0; i < width; i++) {

// a = (argb[index] & 0xff000000) >> 24; // a is not used obviously


 R = (argb[index] & 0xff0000) >> 16;
 G = (argb[index] & 0xff00) >> 8;
 B = (argb[index] & 0xff) >> 0;

 // well known RGB to YUV algorithm


 Y = ((66 * R + 129 * G + 25 * B + 128) >> 8) + 16;
 U = ((-38 * R - 74 * G + 112 * B + 128) >> 8) + 128;
 V = ((112 * R - 94 * G - 18 * B + 128) >> 8) + 128;

 // NV21 has a plane of Y and interleaved planes of VU each sampled by a factor of 2


 // meaning for every 4 Y pixels there are 1 V and 1 U. Note the sampling is every other


 // pixel AND every other scanline.


 yuv420sp[yIndex++] = (byte) ((Y < 0) ? 0 : ((Y > 255) ? 255 : Y));
 if (j % 2 == 0 && index % 2 == 0) {
  yuv420sp[uvIndex++] = (byte) ((V < 0) ? 0 : ((V > 255) ? 255 : V));
  yuv420sp[uvIndex++] = (byte) ((U < 0) ? 0 : ((U > 255) ? 255 : U));
 }

 index++;
 }
 }
 }

 /**

 * 获取夹了时间戳的的数据

 *

 * @return

 */
 private Frame getFrameData() {
 synchronized (MediaCodec.class) {//记得加锁


 if (timeDataContainer.isEmpty()) {
 return null;
 }

 //从队列中获取数据


 Frame frame = timeDataContainer.remove(0);////取出后将此数据remove掉 既能保证PCM数据块的取出顺序 又能及时释放内存


 //转回YUV420sp 120-160ms


 frame.data = getNV21(dstWidth, dstHeight, frame.bitmap);

 return frame;
 }
 }

 /*

 * 旋转图片

 * @param angle

 * @param bitmap

 * @return Bitmap

 */
 public Bitmap rotaingImageView(int angle, Bitmap bitmap) {
 //旋转图片 动作


 Matrix matrix = new Matrix();
 matrix.postRotate(angle);
 // 创建新的图片


 return Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
 }

 /**

 * 初始化解码器

 */
 private void initMediaDecode(String mime) {
 try {
 //创建解码器


 mediaDecode = MediaCodec.createDecoderByType(mime);
 mediaDecode.configure(format, null, null, 0);
 } catch (IOException e) {
 e.printStackTrace();
 }

 if (mediaDecode == null) {
 JLog.e(tag, "create mediaDecode failed");
 return;
 }
 mediaDecode.start();
 decodeInputBuffers = mediaDecode.getInputBuffers();
 decodeOutputBuffers = mediaDecode.getOutputBuffers();
 decodeBufferInfo = new MediaCodec.BufferInfo();//用于描述解码得到的byte[]数据的相关信息

 }

 /**

 * 初始化编码器

 */

 private void initMediaEncode(String mime) {
 try {
 MediaFormat format = MediaFormat.createVideoFormat(MediaFormat.MIMETYPE_VIDEO_AVC, dstWidth, dstHeight);
 format.setInteger(MediaFormat.KEY_BIT_RATE, 1024 * 512);
 format.setInteger(MediaFormat.KEY_FRAME_RATE, 27);
 format.setInteger(MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420Flexible);
// format.setInteger(MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420Planar);


 format.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 1);

 mediaEncode = MediaCodec.createEncoderByType(MediaFormat.MIMETYPE_VIDEO_AVC);
 mediaEncode.configure(format, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
 } catch (IOException e) {
 e.printStackTrace();
 }

 if (mediaEncode == null) {
 JLog.e(tag, "create mediaEncode failed");
 return;
 }
 mediaEncode.start();

 }

 @TargetApi(Build.VERSION_CODES.LOLLIPOP)
 private void decode(MediaCodec.BufferInfo videoInfo, int inputIndex) {


 mediaDecode.queueInputBuffer(inputIndex, 0, videoInfo.size, videoInfo.presentationTimeUs, videoInfo.flags);//通知MediaDecode解码刚刚传入的数据


 //获取解码得到的byte[]数据 参数BufferInfo上面已介绍 10000同样为等待时间 同上-1代表一直等待,0代表不等待。此处单位为微秒


 //此处建议不要填-1 有些时候并没有数据输出,那么他就会一直卡在这 等待


 MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
 int outputIndex = mediaDecode.dequeueOutputBuffer(bufferInfo, 50000);

 switch (outputIndex) {
 case MediaCodec.INFO_OUTPUT_BUFFERS_CHANGED:
 JLog.d(tag, "INFO_OUTPUT_BUFFERS_CHANGED");
 decodeOutputBuffers = mediaDecode.getOutputBuffers();
 break;
 case MediaCodec.INFO_OUTPUT_FORMAT_CHANGED:
 JLog.d(tag, "New format " + mediaDecode.getOutputFormat());
 break;
 case MediaCodec.INFO_TRY_AGAIN_LATER:
 JLog.d(tag, "dequeueOutputBuffer timed out!");
 break;
 default:


 ByteBuffer outputBuffer;
 byte[] frame;
 while (outputIndex >= 0) {//每次解码完成的数据不一定能一次吐出 所以用while循环,保证解码器吐出所有数据

  outputBuffer = decodeOutputBuffers[outputIndex];//拿到用于存放PCM数据的Buffer

  frame = new byte[bufferInfo.size];//BufferInfo内定义了此数据块的大小

  outputBuffer.get(frame);//将Buffer内的数据取出到字节数组中

  outputBuffer.clear();//数据取出后一定记得清空此Buffer MediaCodec是循环使用这些Buffer的,不清空下次会得到同样的数据


  handleFrameData(frame, videoInfo);//自己定义的方法,供编码器所在的线程获取数据,下面会贴出代码


  mediaDecode.releaseOutputBuffer(outputIndex, false);//此操作一定要做,不然MediaCodec用完所有的Buffer后 将不能向外输出数据

  outputIndex = mediaDecode.dequeueOutputBuffer(decodeBufferInfo, 50000);//再次获取数据,如果没有数据输出则outputIndex=-1 循环结束

 }
 break;
 }
 }


 /**

 * 编码

 */
 private void encode() {


 //获取解码器所在线程输出的数据


 byte[] chunkTime;
 Frame frame = getFrameData();
 if (frame == null) {
 return;
 }
 chunkTime = frame.data;
 int inputIndex = mediaEncode.dequeueInputBuffer(-1);//同解码器

 if (inputIndex < 0) {
 JLog.d("px", "dequeueInputBuffer return inputIndex " + inputIndex + ",then break");
 mediaEncode.signalEndOfInputStream();
 }

 ByteBuffer inputBuffer = mediaEncode.getInputBuffers()[inputIndex];//同解码器

 inputBuffer.clear();//同解码器

 inputBuffer.put(chunkTime);//PCM数据填充给inputBuffer

 inputBuffer.limit(frame.videoInfo.size);

 mediaEncode.queueInputBuffer(inputIndex, 0, chunkTime.length, frame.videoInfo.presentationTimeUs, frame.videoInfo.flags);//通知编码器 编码


 MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
 int outputIndex = mediaEncode.dequeueOutputBuffer(bufferInfo, 50000);//同解码器

 switch (outputIndex) {
 case MediaCodec.INFO_OUTPUT_BUFFERS_CHANGED:
 JLog.d(tag, "INFO_OUTPUT_BUFFERS_CHANGED");
 break;
 case MediaCodec.INFO_OUTPUT_FORMAT_CHANGED:
 MediaFormat outputFormat = mediaEncode.getOutputFormat();
 outputFormat.setInteger(MediaFormat.KEY_ROTATION, videoRotation);
 JLog.d(tag, "mediaEncode find New format " + outputFormat);
 //向合成器添加视频轨


 videoTrackIndex = muxer.addTrack(outputFormat);
 muxer.start();
 break;
 case MediaCodec.INFO_TRY_AGAIN_LATER:
 JLog.d(tag, "dequeueOutputBuffer timed out!");
 break;
 default:
 ByteBuffer outputBuffer;
 while (outputIndex >= 0) {//同解码器

  outputBuffer = mediaEncode.getOutputBuffers()[outputIndex];//拿到输出Buffer


  muxer.writeSampleData(videoTrackIndex, outputBuffer, bufferInfo);
//  JLog.d("px", "writeSampleData:" + bufferInfo.size);




  mediaEncode.releaseOutputBuffer(outputIndex, false);

  outputIndex = mediaEncode.dequeueOutputBuffer(bufferInfo, 50000);
 }
 break;
 }
 }

 private void release() {
 //全部写完后释放MediaMuxer和MediaExtractor


 extractor.release();
 mediaDecode.release();
 mediaEncode.release();
 muxer.stop();
 muxer.release();

 }

 private DecodeRunnable decodeRunnable;
 private EncodeRunnable encodeRunnable;

 /**

 * 解码线程

 */
 private class DecodeRunnable extends Thread {

 @Override
 public void run() {
 decodeOver = false;
 while (!decodeOver) {
 try {
  extract();
 } catch (Exception e) {
  //抓住删除文件造成的异常


  JLog.e("px", e.toString());
 }
 synchronized (encodeRunnable) {
  encodeRunnable.notify();
 }
 }
 }

 }

 /**

 * 编码线程

 */
 private class EncodeRunnable extends Thread {

 @Override
 public void run() {
 encoding = true;
 while (encoding) {
 if (timeDataContainer.isEmpty()) {
  if (decodeOver) {//解码完成,缓存也清空了

  break;
  }
  try {
  synchronized (encodeRunnable) {
  wait();
  }
  } catch (InterruptedException e) {
  e.printStackTrace();
  }
 } else {
  encode();
 }
 }
 release();
 encoding = false;
 handler.sendEmptyMessage(-2);//发送消息完成任务

 }
 }


 android.os.Handler handler = new android.os.Handler() {
 @Override
 public void handleMessage(Message msg) {
 switch (msg.what) {
 case -2:
  onComplete();
  break;
 default:
  break;
 }
 }
 };

 public void onComplete() {
 if (mDelete) {//delete请求,是在cancel事件前提下

 mDelete = false;
 new File(mVideo.srcPath).delete();//主动请求删除,删源文件,和数据库

 codecDao.deleteItem(mVideo);
 JLog.d("px", "delete file " + mVideo.srcPath);
 } else {
 mVideo.finish = mCancel ? 0 : 100;
 codecDao.createOrUpdate(mVideo);//更新数据库状态为已完成,或闲置中

 }
 if (mCancel) {//中途取消

 mCancel = false;
 new File(mVideo.dstPath).delete();//取消,删除目标文件

 JLog.d("px", "delete file " + mVideo.dstPath);
 } else {//顺利完成

 new File(mVideo.srcPath).delete();//成功,删除源文件

 JLog.d("px", "delete file " + mVideo.srcPath);
 }
 if (mListener != null) {
 mListener.onCodecFinish(mVideo);
 }
 if (!videos.isEmpty()) {
 VideoCodecModel video = videos.remove(0);
 start(video);
 }
 }

 class Frame {
 MediaCodec.BufferInfo videoInfo;
 byte[] data;
 Bitmap bitmap;

 public Frame(MediaCodec.BufferInfo videoInfo, Bitmap bitmap) {
 this.videoInfo = videoInfo;
 this.bitmap = bitmap;
 }
 }

 private long getInterval() {
 //用第一二帧获取帧间隔


 long videoSampleTime;
 ByteBuffer buffer = ByteBuffer.allocate(1024 * 512);
 //获取源视频相邻帧之间的时间间隔。(1)


 extractor.readSampleData(buffer, 0);
 //skip first I frame


 if (extractor.getSampleFlags() == MediaExtractor.SAMPLE_FLAG_SYNC)
 extractor.advance();
 extractor.readSampleData(buffer, 0);
 long firstVideoPTS = extractor.getSampleTime();
 extractor.advance();
 extractor.readSampleData(buffer, 0);
 long SecondVideoPTS = extractor.getSampleTime();
 videoSampleTime = Math.abs(SecondVideoPTS - firstVideoPTS);
 JLog.d(tag, "videoSampleTime is " + videoSampleTime);
 return videoSampleTime;
 }

 @Override
 public int onStartCommand(Intent intent, int flags, int startId) {
 JLog.d(TAG, "onStartCommand");
 super.onStartCommand(intent, flags, startId);
 if (intent == null) {
 return START_NOT_STICKY;
 }
 int action = intent.getIntExtra("action", 0);
 if (action == REQUEST_CODEC) {
 VideoCodecModel video = (VideoCodecModel) intent.getSerializableExtra("video");
 video = codecDao.addItem(video);
 if (!encoding) {
 start(video);
 } else {
 videos.add(video);
 }
 } else if (action == REQUEST_CODEC_CANCEL) {
 VideoCodecModel video = (VideoCodecModel) intent.getSerializableExtra("video");
 mDelete = intent.getBooleanExtra("delete", false);//是否删除旧文件

 JLog.d("px", "----- onStartCommand action " + action + " is delete?" + mDelete);
 mBinder.cancel(video);
 }
 return START_NOT_STICKY;
 }

 @Nullable
 @Override
 public IBinder onBind(Intent intent) {
 JLog.d(TAG, "onBind");
 return mBinder;
 }

 private CodecBinder mBinder = new CodecBinder();
 private VideoCodecModel mVideo;
 //video下载的任务队列


 private List<VideoCodecModel> videos = new ArrayList<>();

 public static final int REQUEST_CODEC = 0x183;
 public static final int REQUEST_CODEC_CANCEL = 0x184;

 public class CodecBinder extends Binder {
 /**

 * @param video

 * @return 是否可以执行, 或等待执行

 */
 public boolean start(VideoCodecModel video) {
 video = codecDao.addItem(video);
 if (!encoding) {
 TestCodecService.this.start(video);
 } else {
 videos.add(video);
 }
 return !encoding;
 }

 public void setOnProgressChangeListener(OnProgressChangeListener l) {
 mListener = l;
 }

 public VideoCodecModel getCurrentVideo() {
 return mVideo;
 }

 public void cancel(VideoCodecModel video) {
 if (mVideo.equals(video)) {//正在处理

 decodeOver = true;//控制解码线程结束

 encoding = false;//控制编码线程结束

 mCancel = true;//控制结束后删除文件等

 } else {//视频没有正在处理

 boolean flag = videos.remove(video);
 if (flag) {
  JLog.d("px", "cancel render task sucess");
 } else {
  //并没有这个任务


  JLog.d("px", "cancel render task fail,seems this video not in renderring queen");
 }
 //删除源文件


 if (mDelete) {
  mDelete = false;
  new File(video.srcPath).delete();
  codecDao.deleteItem(video);
 }
 }
 }

 public List<VideoCodecModel> getVideoList() {
 return videos;
 }

 public void removeListener() {
 mListener = null;
 }
 }

 private void start(VideoCodecModel video) {
 if (video == null) {
 return;
 }
 if (!new File(video.srcPath).exists()) {
 Toast.makeText(this, "该视频缓存文件可能已经被删除", Toast.LENGTH_SHORT).show();
 video.finish = -100;
 codecDao.createOrUpdate(video);
 return;
 }
 mVideo = video;
 if (mListener != null) {
 mListener.onCodecStart(mVideo);
 }
 mVideo.finish = 50;//改成处理中

 codecDao.createOrUpdate(mVideo);

 Runnable runnable = new Runnable() {
 @Override
 public void run() {
 init(mVideo.srcPath, mVideo.dstPath);
 decodeRunnable = new DecodeRunnable();
 decodeRunnable.start();
 encodeRunnable = new EncodeRunnable();
 encodeRunnable.start();
 }
 };
 AsyncTaskExecutor.getExecutor().execute(runnable);
 }

 private OnProgressChangeListener mListener;

 public interface OnProgressChangeListener {
 void onProgress(int progress, int max);

 void onCodecStart(VideoCodecModel video);

 void onCodecFinish(VideoCodecModel video);
 }

}


//这是模型类


import com.j256.ormlite.field.DatabaseField;
import com.j256.ormlite.table.DatabaseTable;

import java.io.Serializable;

/**

 * Created by user on 2016/8/29.

 */
@DatabaseTable(tableName = "video_codec_task")
public class VideoCodecModel implements Serializable {

 private static final long serialVersionUID = -1307249622002520298L;
 @DatabaseField
 public String srcPath;
 @DatabaseField
 public String dstPath;
 @DatabaseField
 public long videoCreateTime;
 @DatabaseField(generatedId = true)
 public int id;
 //0为被限制的状态,50为渲染中,或渲染队列中,100为已完成,-100为已删除,


 @DatabaseField
 public int finish = 0;
 @DatabaseField
 public String serno;

 //操作是用到,不需要存数据库


 public boolean select;

 public VideoCodecModel(String srcPath, String dstPath, long videoCreateTime) {
 this.srcPath = srcPath;
 this.videoCreateTime = videoCreateTime;
 this.dstPath = dstPath;
 }

 public VideoCodecModel() {
 }

 public String getSrcPath() {
 return srcPath;
 }

 public void setSrcPath(String srcPath) {
 this.srcPath = srcPath;
 }

 public String getDstPath() {
 return dstPath;
 }

 public void setDstPath(String dstPath) {
 this.dstPath = dstPath;
 }

 public long getVideoCreateTime() {
 return videoCreateTime;
 }

 public void setVideoCreateTime(long videoCreateTime) {
 this.videoCreateTime = videoCreateTime;
 }

 public boolean isSelect() {
 return select;
 }

 public void setSelect(boolean select) {
 this.select = select;
 }

 @Override
 public boolean equals(Object o) {
 if (this == o) return true;
 if (!(o instanceof VideoCodecModel)) return false;

 VideoCodecModel that = (VideoCodecModel) o;

 if (videoCreateTime != that.videoCreateTime) return false;
 if (!srcPath.equals(that.srcPath)) return false;
 return dstPath.equals(that.dstPath);

 }
}


//用来查看水印任务完成状态,和监控Service运行的界面Activity,,Activity的打开与否,不影响服务的运行
import android.annotation.TargetApi;
import android.app.ProgressDialog;
import android.content.ComponentName;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.ServiceConnection;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Build;
import android.os.Bundle;
import android.os.IBinder;
import android.os.Message;
import android.support.annotation.Nullable;
import android.util.Log;
import android.view.Gravity;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.PopupMenu;
import android.widget.ProgressBar;
import android.widget.TextView;

import ...

import java.io.File;
import java.lang.ref.WeakReference;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

/**

 * Created by user on 2016/8/29.

 */
public class ShowCodecActivity extends BaseActivity implements TestCodecService.OnProgressChangeListener, View.OnClickListener {

 private TextView noneTipsView;
 private List<VideoCodecModel> videos = new ArrayList<>(), cordingVideos;
 private ListView listView;
 private BaseAdapter adapter;

 private View firstTips;
 @Nullable
 VideoCodecModel curShowVideo, curRenderVideo;
 TestCodecService.CodecBinder binder;
 private ProgressBar progressBar;
 ServiceConnection connection;

 VideoCodecDao codecDao;
 private SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");

 private boolean mEditMode = false;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_show_codec);
 setTitle("签约视频列表");
 initView();
 if (getIntent() != null) {
 curShowVideo = (VideoCodecModel) getIntent().getSerializableExtra("video");
 }
 codecDao = VideoCodecDao.getInstance(this);
 final Intent intent = new Intent(this, TestCodecService.class);
 connection = new ServiceConnection() {
 @Override
 public void onServiceConnected(ComponentName name, IBinder service) {
 Log.d("px", "onServiceConnected");
 binder = (TestCodecService.CodecBinder) service;
 binder.setOnProgressChangeListener(ShowCodecActivity.this);
 videos.clear();
 curRenderVideo = binder.getCurrentVideo();
 cordingVideos = binder.getVideoList();
 videos.addAll(codecDao.queryAll());

 notifyChange();

 }

 @Override
 public void onServiceDisconnected(ComponentName name) {

 }
 };
 bindService(intent, connection, Context.BIND_AUTO_CREATE);
 }

 private void notifyChange() {
 if (adapter == null) {
 adapter = new BaseAdapter() {
 @Override
 public int getCount() {
  return videos.size();
 }

 @Override
 public VideoCodecModel getItem(int position) {
  return videos.get(position);
 }

 @Override
 public long getItemId(int position) {
  return 0;
 }

 @Override
 public View getView(int position, View convertView, ViewGroup parent) {
  final Holder holder;
  if (convertView == null) {
  convertView = View.inflate(ShowCodecActivity.this, R.layout.item_show_codec, null);
  holder = new Holder();
  holder.bar = (ProgressBar) convertView.findViewById(R.id.pb_codec);
  holder.status = (TextView) convertView.findViewById(R.id.status);
  holder.serno = (TextView) convertView.findViewById(R.id.serno);
  holder.select = convertView.findViewById(R.id.select);
  holder.time = (TextView) convertView.findViewById(R.id.time);
  holder.operate = (TextView) convertView.findViewById(R.id.operate);
  holder.checkBox = (CheckBox) convertView.findViewById(R.id.cb_select);
  convertView.setTag(holder);
  } else {
  holder = (Holder) convertView.getTag();
  }
  final VideoCodecModel video = getItem(position);
  if (video.finish == 100) {
  holder.status.setText("已完成");
  holder.operate.setVisibility(View.VISIBLE);
  holder.operate.setText("操作");
  } else if (video.finish == -100) {
  holder.status.setText("已删除");
  holder.operate.setVisibility(View.INVISIBLE);
  } else if (video.equals(curRenderVideo)) {
  progressBar = holder.bar;
  holder.status.setText("处理中");
  holder.operate.setVisibility(View.INVISIBLE);
  } else if (cordingVideos.contains(video)) {
  holder.status.setText("等待中");
  holder.operate.setVisibility(View.VISIBLE);
  holder.operate.setText("取消");
  } else {
  holder.status.setText("未处理");
  holder.operate.setVisibility(View.VISIBLE);
  holder.operate.setText("开始");
  }
  holder.operate.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View v) {
  if (video.finish == 100) {
  operate(holder.status, video);
  } else if (video.finish == -100) {
  return;
  } else if (video.equals(curRenderVideo)) {//已经在编码中,不可操作

  return;
  } else if (cordingVideos.contains(video)) {//已经在编码队列中,可取消

  binder.cancel(video);
  holder.status.setText("未处理");
  holder.operate.setVisibility(View.VISIBLE);
  holder.operate.setText("开始");
  } else {
  boolean immedia = binder.start(video);
  if (immedia) {
   holder.status.setText("处理中");
   holder.operate.setVisibility(View.INVISIBLE);
  } else {
   holder.status.setText("等待中");
   holder.operate.setVisibility(View.VISIBLE);
   holder.operate.setText("取消");
  }
  }
  }
  });
  holder.select.setVisibility(video.equals(curShowVideo) ? View.VISIBLE : View.GONE);
  holder.serno.setText(video.serno);
  holder.time.setText(dateFormat.format(new Date(video.videoCreateTime)));

  holder.checkBox.setVisibility(mEditMode ? View.VISIBLE : View.GONE);
  holder.checkBox.setChecked(video.isSelect());
  holder.checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
  @Override
  public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
  video.setSelect(isChecked);
  }
  });
  return convertView;
 }
 };
 listView.setAdapter(adapter);
 } else {
 adapter.notifyDataSetChanged();
 }
 noneTipsView.setVisibility(videos.isEmpty() ? View.VISIBLE : View.GONE);
 more.setVisibility(mEditMode ? View.VISIBLE : View.GONE);
 back.setVisibility(mEditMode ? View.INVISIBLE : View.VISIBLE);
 checkBox.setVisibility(mEditMode ? View.VISIBLE : View.GONE);
 }

 class Holder {
 ProgressBar bar;
 TextView status, serno, time, operate;
 View select;
 CheckBox checkBox;
 }

 private void initView() {
 listView = (ListView) findViewById(R.id.lv_codec);
 noneTipsView = (TextView) findViewById(R.id.tv_none);
 listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
 @Override
 public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
 VideoCodecModel video = videos.get(position);
 operate(view, video);
 }
 });
 listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
 @Override
 public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
 if (mEditMode) {
  return false;
 }
 mEditMode = true;
 //启动编辑模式不记住从前的选中状态


 for (VideoCodecModel video : videos) {
  if (video.select)
  video.select = false;
 }
 checkBox.setChecked(false);
 notifyChange();
 return true;
 }
 });
 firstTips = findViewById(R.id.ll_tips);
 boolean visable = Preferences.getBoolean("firstShowCodec", true);
 firstTips.setVisibility(visable ? View.VISIBLE : View.GONE);
 if (visable)
 findViewById(R.id.btn_noshow).setOnClickListener(new View.OnClickListener() {
 @Override
 public void onClick(View v) {
  Preferences.put("firstShowCodec", false);
  firstTips.setVisibility(View.GONE);
 }
 });
 checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
 @Override
 public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
 for (VideoCodecModel model : videos) {
  model.setSelect(isChecked);
 }
 notifyChange();
 }
 });
 more.setText("操作");
 more.setOnClickListener(this);
 }

 private void operate(View view, final VideoCodecModel video) {
 if (video.finish != 100) {
 return;
 }
 PopupMenu popupMenu = new PopupMenu(ShowCodecActivity.this, view);
 popupMenu.getMenu().add(1, 0, 0, "预览或发送");
 popupMenu.getMenu().add(1, 1, 1, "删除");
 popupMenu.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
 @Override
 public boolean onMenuItemClick(MenuItem item) {

 switch (item.getItemId()) {
  case 0:
  previewVideo(video.dstPath);
  break;
  case 1:
  File file = new File(video.dstPath);
  if (file.exists()) {
  file.delete();
  }
  codecDao.deleteItem(video);
  videos.remove(video);
  if (cordingVideos.contains(video)) {
  binder.cancel(video);
  }
  notifyChange();
  break;
 }

 return true;
 }
 });
 popupMenu.show();
 }


 @Override
 public void onProgress(int progress, int max) {
 if (progressBar != null) {
 progressBar.setMax(max);
 progressBar.setProgress(progress);
 }
 }

 @Override
 public void onCodecStart(VideoCodecModel video) {
 JLog.d("px", "onCodecStart");
 curRenderVideo = video;
 int index = videos.indexOf(video);
 if (index >= 0) {
 View child = listView.getChildAt(index);
 Holder holder = (Holder) child.getTag();
 holder.status.setText("处理中");
 holder.operate.setVisibility(View.INVISIBLE);
 progressBar = holder.bar;
 }
 }

 @Override
 public void onCodecFinish(VideoCodecModel video) {
 JLog.d("px", "onCodecFinish");
 if (progressBar != null) {
 progressBar.setProgress(0);
 }
 int index = videos.indexOf(video);
 videos.get(index).finish = 100;
 if (index >= 0) {
 View child = listView.getChildAt(index);
 Holder holder = (Holder) child.getTag();
 holder.status.setText("已完成");
 holder.operate.setVisibility(View.VISIBLE);
 holder.operate.setText("操作");
 progressBar = null;
 }
 }

 @Override
 protected void onDestroy() {
 if (binder != null)
 binder.removeListener();
 unbindService(connection);
 super.onDestroy();
 }

 private void previewVideo(String filePath) {
 //预览录像


 Intent intent = new Intent(Intent.ACTION_VIEW);
 String type = "video/mp4";
 Uri uri = Uri.parse("file://" + filePath);
 intent.setDataAndType(uri, type);
 startActivity(intent);
 }

 @Override
 public void onBackPressed() {
 if (mEditMode) {
 mEditMode = false;
 notifyChange();
 return;
 }
 super.onBackPressed();
 }

 @Override
 public void onClick(View v) {
 switch (v.getId()) {
 case R.id.more:
 PopupMenu menu = new PopupMenu(this, v);
// menu.getMenu().add(1, 0, 0, "发送");


 menu.getMenu().add(1, 1, 1, "删除");
 menu.getMenu().add(1, 2, 2, "取消");
 menu.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
  @Override
  public boolean onMenuItemClick(MenuItem item) {
  switch (item.getItemId()) {
  case 0:
  break;
  case 1:
  deleteSelect();
  break;
  case 2:
  mEditMode = false;
  notifyChange();
  break;
  }
  return true;
  }
 });
 menu.show();
 break;
 }
 }

 //删除所选


 private void deleteSelect() {
 final ProgressDialog dialog = ProgressDialog.show(this, null, null);
 AsyncTask<String, String, Boolean> task = new AsyncTask<String, String, Boolean>() {
 @Override
 protected Boolean doInBackground(String... params) {
 boolean has = false;//是否选到可以删除的,有可能并未有任何选择

 for (VideoCodecModel video : videos) {
  if (video.select) {
  File file;
  if (video.finish == 100) {
  file = new File(video.dstPath);
  } else {
  file = new File(video.srcPath);
  }
  if (file.exists()) {
  file.delete();
  }
  codecDao.deleteItem(video);
  if (!has) {
  has = true;
  }
  }
 }
 if (has) {
  videos.clear();
  videos.addAll(codecDao.queryAll());
 }

 return has;
 }

 @Override
 protected void onPostExecute(Boolean s) {
 mEditMode = false;
 notifyChange();
 dialog.dismiss();
 }
 };
 task.executeOnExecutor(AsyncTaskExecutor.getExecutor());
 }
}
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