我在使用android mediacodec编码和解码h264时出错了颜色

Question

I'm learning how to use mediacodec recently,it seems to have some problems.I wrote a demo which gets data from camera preview ,encode it into h264 and decode the h264 onto a surfaceview,but it seems the corlor was wrong,just like this: wrong corlor

i've tried to send the h264 i got over rtp and play by ffplay,the corlor was wrong too. i'm confuse about that.anybody knows how to fix it?since i'm new here and not good at English,请多指教(Chinese).Here is my code ` package com.example.androidcodec;

import java.nio.ByteBuffer;

import android.media.MediaCodec;
import android.media.MediaCodecInfo;
import android.media.MediaFormat;
import android.util.Log;
import android.view.Surface;

public class Encoder {
    private byte[] sps;
    private byte[] pps;
    private MediaCodec mEncoder;
    private int width, height;
    private byte[] yuv420;
    private byte[] mInfo = null;
    private MediaCodec mDecoder;
    private Surface surface;
    private int framerate;
    private int bitrate;

    public Encoder(int width, int height, int framerate, int bitrate,Surface surface) {
        this.surface = surface;
        this.width = width;
        this.height = height;
        this.framerate = framerate;
        this.bitrate = bitrate;
        yuv420 = new byte[width * height * 3 / 2];
        mEncoder = MediaCodec.createEncoderByType("video/avc");
        MediaFormat mediaFormat = MediaFormat.createVideoFormat("video/avc", width, height);
        mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, bitrate);
        mediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, framerate);
        mediaFormat.setInteger(MediaFormat.KEY_COLOR_FORMAT, MediaCodecInfo.CodecCapabilities.COLOR_FormatYUV420Planar);
        mediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 1);
        mEncoder.configure(mediaFormat, null, null, MediaCodec.CONFIGURE_FLAG_ENCODE);
        mEncoder.start();
    }

    public void close() {
        try {
            mEncoder.stop();
            mEncoder.release();
            mEncoder = null;
            mDecoder.stop();
            mDecoder.release();
            mDecoder = null;
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    public int offerEncoder(byte[] input, byte[] output) {
        int pos = 0;
        swapYV12toI420(input, yuv420, width, height);
        ByteBuffer[] inputBuffers = mEncoder.getInputBuffers();
        ByteBuffer[] outputBuffers = mEncoder.getOutputBuffers();
        int inputBufferIndex = mEncoder.dequeueInputBuffer(-1);
        if (inputBufferIndex >= 0) {
            ByteBuffer inputBuffer = inputBuffers[inputBufferIndex];
            inputBuffer.clear();
            inputBuffer.put(yuv420);
            mEncoder.queueInputBuffer(inputBufferIndex, 0, yuv420.length, 0, 0);
        }
        MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
        int outputBufferIndex = mEncoder.dequeueOutputBuffer(bufferInfo, 0);
        while (outputBufferIndex >= 0) {
            ByteBuffer outputBuffer = outputBuffers[outputBufferIndex];
            byte[] outData = new byte[bufferInfo.size];
            outputBuffer.get(outData);
            if (mInfo != null) {
                System.arraycopy(outData, 0, output, pos, outData.length);
                pos += outData.length;
            } else {
                ByteBuffer spsPpsBuffer = ByteBuffer.wrap(outData);
                if (spsPpsBuffer.getInt() == 0x00000001) {
                    mInfo = new byte[outData.length];
                    System.arraycopy(outData, 0, mInfo, 0, outData.length);
                    findSpsAndPps(mInfo);
                    initDecoder();
                }else {
                    return -1;
                }
            }
            mEncoder.releaseOutputBuffer(outputBufferIndex, false);  
            outputBufferIndex = mEncoder.dequeueOutputBuffer(bufferInfo, 0);
        }

        return pos;
    }

    private void initDecoder() {
        mDecoder = MediaCodec.createDecoderByType("video/avc");
        MediaFormat mediaFormat = MediaFormat.createVideoFormat("video/avc", width, height);
        mediaFormat.setByteBuffer("csd-0"  , ByteBuffer.wrap(sps));
        mediaFormat.setByteBuffer("csd-1", ByteBuffer.wrap(pps));
        mediaFormat.setInteger(MediaFormat.KEY_MAX_INPUT_SIZE, height*width);  
        mediaFormat.setInteger(MediaFormat.KEY_BIT_RATE, bitrate);
        mediaFormat.setInteger(MediaFormat.KEY_FRAME_RATE, framerate);
        mediaFormat.setInteger(MediaFormat.KEY_I_FRAME_INTERVAL, 1);
        mDecoder.configure(mediaFormat, surface, null, 0);
        mDecoder.start();

    }

    public void onFrame(byte[] buf, int offset, int length) {

        ByteBuffer[] inputBuffers = mDecoder.getInputBuffers();
        int inputBufferIndex = mDecoder.dequeueInputBuffer(-1);
        if (inputBufferIndex >= 0) {
            ByteBuffer inputBuffer = inputBuffers[inputBufferIndex];
            inputBuffer.clear();
            inputBuffer.put(buf, offset, length);
            int capacity = inputBuffer.capacity();
            Log.e("tag", "capacity < length?"+":"+(capacity < length)+"......................");
            mDecoder.queueInputBuffer(inputBufferIndex, 0, length, System.currentTimeMillis(), 0);
        }

        MediaCodec.BufferInfo bufferInfo = new MediaCodec.BufferInfo();
        int outputBufferIndex = mDecoder.dequeueOutputBuffer(bufferInfo, 0);
        Log.e("tag", outputBufferIndex+"onFrame.........................................................");
        while (outputBufferIndex >= 0) {
            mDecoder.releaseOutputBuffer(outputBufferIndex, true);
            outputBufferIndex = mDecoder.dequeueOutputBuffer(bufferInfo, 0);
        }
    }


    // yv12 转 yuv420p yvu -> yuv
    private void swapYV12toI420(byte[] yv12bytes, byte[] i420bytes, int width, int height) {
        System.arraycopy(yv12bytes, 0, i420bytes, 0, width * height);
        System.arraycopy(yv12bytes, width * height + width * height / 4, i420bytes, width * height, width * height / 4);
        System.arraycopy(yv12bytes, width * height, i420bytes, width * height + width * height / 4, width * height / 4);
    }

    private void findSpsAndPps(byte[] config) {
        Log.e("tag", printBuffer(config,0,config.length-1));
        int spsEnd = 1;
        for(int i = 4; i < config.length-4; i ++){
            if(config[i]==0X00 && config[i+1]==0X00 &&config[i+2]==0X00 &&config[i+3]==0X01){
                spsEnd = i-1;
                break;
            }
        }
        Log.e("tag", spsEnd-3+"...............................");
        sps = new byte[spsEnd-3];
        pps = new byte[config.length-spsEnd-5];
        System.arraycopy(config,4,sps,0,spsEnd-3);
        System.arraycopy(config,spsEnd+5,pps,0,config.length-spsEnd-5);
    }

    public byte[] getSps() {
        return sps;
    }

    public byte[] getPps() {
        return pps;
    }

    protected static String printBuffer(byte[] buffer, int start,int end) {
        String str = "";
        for (int i=start;i<end;i++) str+=","+Integer.toHexString(buffer[i]&0xFF);
        return str+"\r\n";
    }
}

`

Answer 1

我自己解决了这个问题，我在details.parameters.setPreviewFormat中犯了一个错误，应该在预览开始之前调用而不是参数.setPictureFormat。