Android ffmpeg Decoding

Source: Internet
Author: User

I recently obtained android ffmpeg decoding. The following describes the process for your reference.

1. ffmpeg Transplantation

There are some articles on ffmpeg porting on the Internet. I tried it many times but finally generated libffmpeg. so is only a few KB. so here is another method. Some articles on the Internet have said that, in fact, I think this method is better, just generate a library.

I modified ffmpeg:

After downloading, unzip to the ffmpeg-1.2.4-android directory, there is a mkconfig. sh file, open this file, you need to modify a few places.

The mkconfig. sh content is as follows:

#!/bin/shexport PREBUILT=/dao/work/tools/android-ndk-r5b/toolchains/arm-linux-androideabi-4.4.3export PLATFORM=/dao/work/tools/android-ndk-r5b/platforms/android-9/arch-armexport TMPDIR=/dao/tmp./configure \--target-os=linux \--arch=arm \--disable-ffmpeg \--disable-ffplay \--disable-ffprobe \--disable-ffserver \--disable-avdevice \--disable-avfilter \--disable-postproc \--disable-swresample \--disable-avresample \--disable-symver \--disable-debug \--disable-stripping \--disable-yasm \--disable-asm \--enable-gpl \--enable-version3 \--enable-nonfree \--disable-doc \--enable-static \--disable-shared \--enable-cross-compile \--prefix=/dao/_install \--cc=$PREBUILT/prebuilt/linux-x86/bin/arm-linux-androideabi-gcc \--cross-prefix=$PREBUILT/prebuilt/linux-x86/bin/arm-linux-androideabi- \--nm=$PREBUILT/prebuilt/linux-x86/bin/arm-linux-androideabi-nm \--extra-cflags="-fPIC -DANDROID -I$PLATFORM/usr/include" \--extra-ldflags="-L$PLATFORM/usr/lib -nostdlib"sed -i 's/HAVE_LRINT 0/HAVE_LRINT 1/g' config.h  sed -i 's/HAVE_LRINTF 0/HAVE_LRINTF 1/g' config.h  sed -i 's/HAVE_ROUND 0/HAVE_ROUND 1/g' config.h  sed -i 's/HAVE_ROUNDF 0/HAVE_ROUNDF 1/g' config.h  sed -i 's/HAVE_TRUNC 0/HAVE_TRUNC 1/g' config.h  sed -i 's/HAVE_TRUNCF 0/HAVE_TRUNCF 1/g' config.h  sed -i 's/HAVE_CBRT 0/HAVE_CBRT 1/g' config.h  sed -i 's/HAVE_CBRTF 0/HAVE_CBRTF 1/g' config.h  sed -i 's/HAVE_ISINF 0/HAVE_ISINF 1/g' config.h  sed -i 's/HAVE_ISNAN 0/HAVE_ISNAN 1/g' config.h  sed -i 's/HAVE_SINF 0/HAVE_SINF 1/g' config.h  sed -i 's/HAVE_RINT 0/HAVE_RINT 1/g' config.hsed -i 's/#define av_restrict restrict/#define av_restrict/g' config.h
You need to set the environment variable at the beginning:

export PREBUILT=/dao/work/tools/android-ndk-r5b/toolchains/arm-linux-androideabi-4.4.3export PLATFORM=/dao/work/tools/android-ndk-r5b/platforms/android-9/arch-armexport TMPDIR=/dao/tmp
This is your NDK path and temporary directory

There is also a need to modify:

--prefix=/dao/_install \
This is the installation directory. Change it to your own directory.

Then run./mkconfig. sh

There should be a warning, don't worry. Execute make directly for a few minutes and the compilation will be completed. Then execute make install

In your installation directory, two directories include and llib will be generated. Here we have transplanted them. Put these files here first and we will use them later.

2. Compiling jni

Create a jni directory under your android project directory (in fact, I created it in another project, I tried to delete the items in the project when running ndk-build) and copied the entire include directory we installed earlier to the jni directory, put all. copy file a to the jni directory to create a new Android. mk file with the following content:

LOCAL_PATH := $(call my-dir)include $(CLEAR_VARS)LOCAL_MODULE := avformatLOCAL_SRC_FILES := libavformat.aLOCAL_CFLAGS :=-IlibavformatLOCAL_EXPORT_C_INCLUDES := libavformatLOCAL_EXPORT_CFLAGS := -IlibavformatLOCAL_EXPORT_LDLIBS := -lloginclude $(PREBUILT_STATIC_LIBRARY)include $(CLEAR_VARS)LOCAL_MODULE := avcodecLOCAL_SRC_FILES := libavcodec.aLOCAL_CFLAGS :=-IlibavcodecLOCAL_EXPORT_C_INCLUDES := libavcodecLOCAL_EXPORT_CFLAGS := -IlibavcodecLOCAL_EXPORT_LDLIBS := -lloginclude $(PREBUILT_STATIC_LIBRARY)include $(CLEAR_VARS)LOCAL_MODULE := avutilLOCAL_SRC_FILES := libavutil.aLOCAL_CFLAGS :=-IlibavutilLOCAL_EXPORT_C_INCLUDES := libavutilLOCAL_EXPORT_CFLAGS := -IlibavutilLOCAL_EXPORT_LDLIBS := -lloginclude $(PREBUILT_STATIC_LIBRARY)include $(CLEAR_VARS)LOCAL_MODULE := swscaleLOCAL_SRC_FILES :=libswscale.aLOCAL_CFLAGS :=-Ilibavutil -IlibswscaleLOCAL_EXPORT_C_INCLUDES := libswscaleLOCAL_EXPORT_CFLAGS := -IlibswscaleLOCAL_EXPORT_LDLIBS := -llog -lavutilinclude $(PREBUILT_STATIC_LIBRARY)include $(CLEAR_VARS)LOCAL_MODULE    := ffmpegutilsLOCAL_SRC_FILES := native.cLOCAL_C_INCLUDES := $(LOCAL_PATH)/includeLOCAL_LDLIBS    := -L$(LOCAL_PATH) -lm -lzLOCAL_STATIC_LIBRARIES := avformat avcodec avutil swscaleinclude $(BUILD_SHARED_LIBRARY)
Create a new native. c file. This is the final file to be called. The content is as follows:

/* * Copyright 2011 - Churn Labs, LLC * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. *//* * This is mostly based off of the FFMPEG tutorial: * * With a few updates to support Android output mechanisms and to update * places where the APIs have shifted. */#include 
    #include #include 
       #define LOG_TAG "FFMPEGSample"#define LOGI(...) __android_log_print(ANDROID_LOG_INFO,LOG_TAG,__VA_ARGS__)#define LOGE(...) __android_log_print(ANDROID_LOG_ERROR,LOG_TAG,__VA_ARGS__)AVCodecContext * pCodecCtx = NULL;AVFrame * pFrame=NULL;AVPacket avpkt;struct SwsContext *swsctx = NULL;AVFrame * picture=NULL;JNIEXPORT jint JNICALL Java_com_dao_iclient_FfmpegIF_getffmpegv(JNIEnv * env, jclass obj){LOGI("getffmpegv");return avformat_version();}JNIEXPORT jint JNICALL Java_com_dao_iclient_FfmpegIF_DecodeInit(JNIEnv * env, jclass obj,jint width,jint height){LOGI("Decode_init");AVCodec * pCodec=NULL;avcodec_register_all(); //av_register_all(); //avcodec_init(); av_init_packet(&avpkt);pCodec=avcodec_find_decoder(CODEC_ID_H264);if(NULL!=pCodec){ pCodecCtx=avcodec_alloc_context3(pCodec); if(avcodec_open2(pCodecCtx,pCodec,NULL)>=0){ pCodecCtx->height = height; pCodecCtx->width = width; pFrame=avcodec_alloc_frame(); } return 1;} elsereturn 0;}JNIEXPORT jint JNICALL Java_com_dao_iclient_FfmpegIF_Decoding(JNIEnv * env, jclass obj,const jbyteArray pSrcData,const jint DataLen,const jbyteArray pDeData){//LOGI("Decoding");int frameFinished;int i,j;int consumed_bytes;jbyte * Buf = (jbyte*)(*env)->GetByteArrayElements(env, pSrcData, 0);jbyte * Pixel= (jbyte*)(*env)->GetByteArrayElements(env, pDeData, 0); = Buf;avpkt.size = DataLen;consumed_bytes=avcodec_decode_video2(pCodecCtx,pFrame,&frameFinished,&avpkt); //av_free_packet(&avpkt); if(frameFinished) {picture=avcodec_alloc_frame();avpicture_fill((AVPicture *) picture, (uint8_t *)Pixel, PIX_FMT_RGB565,pCodecCtx->width,pCodecCtx->height);swsctx = sws_getContext(pCodecCtx->width,pCodecCtx->height, pCodecCtx->pix_fmt,pCodecCtx->width, pCodecCtx->height,PIX_FMT_RGB565, SWS_BICUBIC, NULL, NULL, NULL);sws_scale(swsctx,(const uint8_t* const*)pFrame->data,pFrame->linesize,0,pCodecCtx->height,picture->data,picture->linesize);} (*env)->ReleaseByteArrayElements(env, pSrcData, Buf, 0); (*env)->ReleaseByteArrayElements(env, pDeData, Pixel, 0);return consumed_bytes;}JNIEXPORT jint JNICALL Java_com_dao_iclient_FfmpegIF_DecodeRelease(JNIEnv * env, jclass obj){//LOGI("Decode_release");sws_freeContext(swsctx);av_free_packet(&avpkt);av_free(pFrame);av_free(picture);avcodec_close(pCodecCtx);av_free(pCodecCtx); return 1;}

Finally, we only used two functions: init and decoding. Here we will describe the function naming method as Java _ package name_classname_function name, com. dao. iclient is my package name, FfmpegIF is my class name, And DecodeInit is my function name. if you have already set ndk environment variables in the system, you can directly execute ndk-build in the project directory (here the Directory should not be wrong ). finally, the library file is generated in libs/armeabi/under the project directory.

3. Apply the ffmpeg Library

Added the FfmpegIF class. The content is as follows:

package com.dao.iclient;public class FfmpegIF {public static short TYPE_MODE_DATA = 0;public static short TYPE_MODE_COM = 1;public static int VIDEO_COM_START = 0x00;public static int VIDEO_COM_POSE = 0x01;public static int VIDEO_COM_RUN = 0x02;public static int VIDEO_COM_ACK = 0x03;public static int VIDEO_COM_STOP = 0x04;static public native int getffmpegv();static public native int DecodeInit(int width,int height);static public native int Decoding(byte[] in,int datalen,byte[] out);static public native int DecodeRelease();static {System.loadLibrary("ffmpegutils");}}
Add an ImageView object to the layout file. Here I will decode the received data transmitted over the network. I will post all the code. Here is the content of my main file:

package com.dao.iclient;import;import;import;import;import java.nio.ByteBuffer;import java.util.Timer;import java.util.TimerTask;import;import;import;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.os.SystemClock;import android.view.Menu;import android.widget.ImageView;public class IcoolClient extends Activity {public Socket socket;public ByteBuffer buffer;public ByteBuffer Imagbuf;//net packagepublic static short type = 0;public static int packageLen = 0;public static int sendDeviceID = 0;public static int revceiveDeviceID = 0;public static short sendDeviceType = 0;public static int dataIndex = 0;public static int dataLen = 0;public static int frameNum = 0;public static int commType = 0;//sizepublic static int packagesize;public OutputStream outputStream=null;public InputStream inputStream=null;public int width = 0;public int height = 0;public Bitmap VideoBit;public ImageView mImag;public byte[] mout;protected static final int REFRESH = 0;private Handler mHandler;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_icool_client);mImag = (ImageView)findViewById(;        packagesize = 7 * 4 + 2 * 2;        buffer = ByteBuffer.allocate(packagesize);       // int ffpmegv = FfmpegIF.getffmpegv();        //System.out.println("ffmpeg version is " + ffpmegv);        width = 640;        height = 480;        mout = new byte[width * height * 2];        Imagbuf = ByteBuffer.wrap(mout);        VideoBit = Bitmap.createBitmap(width ,height, Config.RGB_565);        //mImag.postInvalidate();        int ret = FfmpegIF.DecodeInit(width, height);        //System.out.println(" ret is " + ret);        mHandler = new Handler();        new StartThread().start();}final Runnable mUpdateUI = new Runnable() {@Overridepublic void run() {// TODO Auto-generated method stub    VideoBit.copyPixelsFromBuffer(Imagbuf);    mImag.setImageBitmap(VideoBit);}};    class StartThread extends Thread {@Overridepublic void run() {// TODO Auto-generated method stub//;int datasize;try {        socket = new Socket("", 9876);        //System.out.println("socket");        SendCom(FfmpegIF.VIDEO_COM_STOP);        SendCom(FfmpegIF.VIDEO_COM_START);        //new ShowBuffer().start();        inputStream = socket.getInputStream();        byte[] Rbuffer = new byte[packagesize];        while(true) {;//byte2hex(Rbuffer);SystemClock.sleep(3);datasize = getDataL(Rbuffer);if(datasize > 0) {byte[] Data = new byte[datasize];int size;    size =;    FfmpegIF.Decoding(Data, size, mout);    //VideoBit.copyPixelsFromBuffer(Imagbuf);    //mImag.setImageBitmap(VideoBit);;    //System.out.println("read datalen is " + size);    //SystemClock.sleep(10);    SendCom(FfmpegIF.VIDEO_COM_ACK);}        }}catch (IOException e) {            e.printStackTrace();        }}    }    public void SendCom(int comtype) {    byte[] Bbuffer = new byte[packagesize];    try {    outputStream = socket.getOutputStream();    type = FfmpegIF.TYPE_MODE_COM;    packageLen = packagesize;    commType = comtype;    putbuffer();    Bbuffer = buffer.array();    outputStream.write(Bbuffer);    //System.out.println("send done");    } catch (IOException e) {            e.printStackTrace();        }     }        public void putbuffer(){    buffer.clear();        buffer.put(ShorttoByteArray(type));        buffer.put(InttoByteArray(packageLen));        buffer.put(InttoByteArray(sendDeviceID));        buffer.put(InttoByteArray(revceiveDeviceID));        buffer.put(ShorttoByteArray(sendDeviceType));        buffer.put(InttoByteArray(dataIndex));        buffer.put(InttoByteArray(dataLen));        buffer.put(InttoByteArray(frameNum));        buffer.put(InttoByteArray(commType));        //System.out.println("putbuffer done");    }        private static byte[] ShorttoByteArray(short n) {        byte[] b = new byte[2];        b[0] = (byte) (n & 0xff);        b[1] = (byte) (n >> 8 & 0xff);        return b;    }      private static byte[] InttoByteArray(int n) {        byte[] b = new byte[4];        b[0] = (byte) (n & 0xff);        b[1] = (byte) (n >> 8 & 0xff);        b[2] = (byte) (n >> 16 & 0xff);        b[3] = (byte) (n >> 24 & 0xff);        return b;    }       public short getType(byte[] tpbuffer){    short gtype = (short) ((short)tpbuffer[0] + (short)(tpbuffer[1] << 8));    //System.out.println("gtype is " + gtype);    return gtype;    }        public int getPakL(byte[] pkbuffer){    int gPackageLen = ((int)(pkbuffer[2]) & 0xff) | ((int)(pkbuffer[3] & 0xff) << 8) | ((int)(pkbuffer[4] & 0xff) << 16) | ((int)(pkbuffer[5] & 0xff) << 24);    //System.out.println("gPackageLen is " + gPackageLen);    return gPackageLen;    }        public int getDataL(byte[] getbuffer){    int gDataLen = (((int)(getbuffer[20] & 0xff)) | ((int)(getbuffer[21] & 0xff) << 8) | ((int)(getbuffer[22] & 0xff) << 16) | ((int)(getbuffer[23] & 0xff) << 24));    //System.out.println("gDataLen is " + gDataLen);    return gDataLen;    }        public int getFrameN(byte[] getbuffer){    int getFrameN = (int)(((int)(getbuffer[24])) + ((int)(getbuffer[25]) << 8) + ((int)(getbuffer[26]) << 16) + ((int)(getbuffer[27]) << 24));    //System.out.println("getFrameN is " + getFrameN);    return getFrameN;    }        private void byte2hex(byte [] buffer) {          String h = "";          for(int i = 0; i < buffer.length; i++){              String temp = Integer.toHexString(buffer[i] & 0xFF);            if(temp.length() == 1){                temp = "0" + temp;              }              h = h + " "+ temp;          }         // System.out.println(h);    }@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(, menu);return true;}}

Function Description:

MUpdateUI is used to solve the problem that the main process cannot refresh the UI.

The main task of the network communication thread of StartThread is to receive the command packet first, then receive the data packet, and then decode the display.

SendCom command package sending

Putbuffer command package generation, because the server is written in C, and the command package is a struct, so we have done this here. At the same time, we need to pay attention to byte alignment, in C, the long type is 4 bytes, and in Java, the long type is 8 bytes. Note that I have struggled for several hours.

ShorttoByteArray, InttoByteArray network communication format conversion, low bytes before high bytes after

GetType, getPakL, getDataL, getFrameN, and command package-related data acquisition

Byte2hex converts the byte array to the hexadecimal output, which is used for debugging.

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Author: hclydao
No copyright, but please keep this statement for reprinting

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