其实是一个用java实现录像的功能，还没有实现，但解码和转码已经可以。

1.maven环境，pom.xml配置

1 
      
        2         
       
        1.4.1
        3         
        4         
       
        3.4.2
        5         
       
        UTF-8
        6         
       
        3.1.0
        7     
       8 
      
        9 
       
        org.bytedeco
       10 
       
        javacv-platform
       11 
       
        ${javacpp.version}
       12 
      13 
      
       14 
       
        org.bytedeco
       15 
       
        javacpp
       16 
       
        ${javacpp.version}
       17 
      18 
      
       19 
       
        org.bytedeco.javacpp-presets
       20 
       
        ffmpeg-platform
       21 
       
        ${ffmpeg.version}-${javacpp.version}
       22 
      

2.代码

1 package com.br.test;  2   3 import java.io.ByteArrayOutputStream;  4 import java.io.File;  5 import java.io.FileOutputStream;  6 import java.io.IOException;  7 import java.nio.ByteBuffer;  8 import org.bytedeco.javacpp.*;  9 import static org.bytedeco.javacpp.avcodec.*; 10 import static org.bytedeco.javacpp.avformat.*; 11 import static org.bytedeco.javacpp.avutil.*; 12 import static org.bytedeco.javacpp.swscale.*; 13  14 public class NewTest { 15     // Load only once formats and codecs 16     static { 17         av_register_all(); 18 //        avformat_network_init(); 19         avcodec_register_all(); 20     } 21     public int codec_id; 22     public AVCodecContext m_pCodecCtx = null; // URL中视频解码部分内容 23     public AVFrame m_pFrame = null; // 全局使用帧对象 24     public AVFrame m_pFrameRGB = null; 25     public AVCodec m_pCodec = null; 26     public AVCodecParserContext pCodecParserCtx = null; 27     public AVPacket packet = null; 28     public SwsContext m_pImageConvertCtx = null; // 构造全局对象，供sws_scale切割图片使用 29     public SwsContext img_convert_ctx = null; 30     public Integer count = 0; 31     public int count_size; 32     public BytePointer cur_ptr; 33     public FileOutputStream os; 34     private ByteArrayOutputStream myByteArrayOutputStream = new ByteArrayOutputStream(); 35  36     public NewTest() { 37         System.out.println("init begin"); 38  39         m_pFrame = av_frame_alloc(); 40         codec_id = AV_CODEC_ID_H264; 41         m_pFrameRGB = av_frame_alloc(); 42         m_pCodec = avcodec_find_decoder(codec_id); 43  44         if (m_pCodec == null) { 45             System.out.println("Codec not found\n"); 46         } 47         m_pCodecCtx = avcodec_alloc_context3(m_pCodec); 48         if (m_pCodecCtx == null) { 49             System.out.println("Could not allocate video codec context\n"); 50         } 51  52         pCodecParserCtx = av_parser_init(codec_id); 53         if (pCodecParserCtx == null) { 54             System.out.println("Could not allocate video parser context\n"); 55         } 56  57         if (avcodec_open2(m_pCodecCtx, m_pCodec, (PointerPointer
      
       ) null) < 0) { 58             System.out.println("Could not open codec\n"); 59         } 60         img_convert_ctx = sws_getContext(1920, 1088, AV_PIX_FMT_YUV420P, 1920, 1088, AV_PIX_FMT_BGRA, SWS_FAST_BILINEAR, 61                 null, null, (DoublePointer) null); 62  63         packet = new AVPacket(); 64  65         packet = av_packet_alloc(); 66  67         av_new_packet(packet, 30000); 68  69         int numBytes = av_image_get_buffer_size(AV_PIX_FMT_BGRA, 1920, 1088, 1); 70  71         BytePointer rgbData = new BytePointer(av_malloc(numBytes)); 72  73         av_image_fill_arrays(m_pFrameRGB.data(), m_pFrameRGB.linesize(), rgbData, AV_PIX_FMT_BGRA, 1920, 1088, 1); 74  75         System.out.println("init end"); 76     } 77  78     public void dec_loop(byte[] H264) { 79  80         ByteBuffer data = ByteBuffer.allocate(H264.length); 81         data.put(H264); 82         int cur_size = H264.length; 83         IntPointer pktSize = new IntPointer(packet.size()); 84         BytePointer temp_bp = new BytePointer(); 85         while (cur_size > 0) { 86  87             data.flip(); 88             int slen = av_parser_parse2(pCodecParserCtx, m_pCodecCtx, temp_bp, pktSize, new BytePointer(data), cur_size, 89                     AV_NOPTS_VALUE, AV_NOPTS_VALUE, AV_NOPTS_VALUE); 90             packet = packet.size(pktSize.get()); 91  92             data.position(slen); 93             data = data.compact(); 94             cur_size -= slen; 95  96             if (pktSize.get() == 0) { 97                 continue; 98             } 99             packet = packet.data(temp_bp);100             // for(int i = 0;i <5;i++){101             // byte b = packet.data().get(i);102             // System.out.print(byteToHex(b)+" ");103             // }104             // System.out.println("------------------------------!!!!------------------"+packet.size());105             // packet.data().asBuffer();106 107             int asp = avcodec_send_packet(m_pCodecCtx, packet);108 109             if (avcodec_receive_frame(m_pCodecCtx, m_pFrame) == 0) {110                 // m_pFrame.data(0);111                 // y = m_pFrame->data[0];1920*1088112                 // u = m_pFrame->data[1];1920*1088/4113                 // v = m_pFrame->data[2];1920*1088/4114 115                 System.err.println(116                         "->>> decode success   " + "width :" + m_pFrame.width() + " " + "height :" + m_pFrame.height());117 118                 sws_scale(img_convert_ctx, m_pFrame.data(), m_pFrame.linesize(), 0, m_pCodecCtx.height(),119                         m_pFrameRGB.data(), m_pFrameRGB.linesize());120                 BytePointer by_bgra_data = m_pFrameRGB.data(0);121                 try {122 //                    String imgName = "C:/Users/user/Desktop/test/test" + count + ".h264";123 //                    saveImg(m_pFrame, imgName);124 //                    count++;125                     // for (int i = 0; i < 1920 * 1088 * 4; i++) {126                     // myByteArrayOutputStream.write(by_bgra_data.get(i));127                     // }128                     // if (myByteArrayOutputStream.size() == 1920 * 1088 * 4) {129                     // File file = new130                     // File("C://Users//user//Desktop//test//success.yuv");131                     // if (!file.exists()) {132                     // file.createNewFile();133                     // }134                     // FileOutputStream fe = new FileOutputStream(file, true);135                     // fe.write(myByteArrayOutputStream.toByteArray());136                     // fe.flush();137                     // fe.close();138                     // myByteArrayOutputStream.reset();139                     // }140                 } catch (Exception e) {141                     e.printStackTrace();142                 }143             }144             // av_packet_unref(packet);145         }146         // av_packet_free(packet);147     }148 149     public int saveImg(AVFrame pFrame, String out_file) throws IOException {150         AVCodec codec = null;151         AVPacket pkt = null;152         AVStream pAVStream = null;153         int ret = -1;154         AVDictionary avd = new AVDictionary(null);155         int width = pFrame.width(), height = pFrame.height();156         // 分配AVFormatContext对象157         AVFormatContext pFormatCtx = avformat_alloc_context();158         // 设置输出文件格式159         pFormatCtx.oformat(av_guess_format("h264", null, null));160         if (pFormatCtx.oformat() == null) {161             return -1;162         }163         try {164             // 创建并初始化一个和该url相关的AVIOContext165             AVIOContext pb = new AVIOContext();166             if (avio_open(pb, out_file, AVIO_FLAG_READ_WRITE) < 0) {// dont open167                                                                     // file168                 return -1;169             }170             pFormatCtx.pb(pb);171             // 构建一个新stream172             pAVStream = avformat_new_stream(pFormatCtx, codec);173             if (pAVStream == null) {174                 return -1;175             }176             int codec_id = pFormatCtx.oformat().video_codec();177             // 设置该stream的信息178             AVCodecContext pCodecCtx = pAVStream.codec();179             pCodecCtx.codec_id(codec_id);180             pCodecCtx.codec_type(AVMEDIA_TYPE_VIDEO);181             pCodecCtx.pix_fmt(AV_PIX_FMT_YUV420P);182             pCodecCtx.width(width);183             pCodecCtx.height(height);184             pCodecCtx.time_base().num(1);185             pCodecCtx.time_base().den(25);186             pCodecCtx.qmin(10);187             pCodecCtx.qmax(51);188             pCodecCtx.bit_rate(400000);189             pCodecCtx.gop_size(12);190             pCodecCtx.qcompress(0.6f);191 192             if (pCodecCtx.codec_id() == AV_CODEC_ID_H264) {193                 av_dict_set(avd, "preset", "slow", 0);194                 av_dict_set(avd, "tune", "zerolatency", 0);195             }196 197             // Begin Output some information198             av_dump_format(pFormatCtx, 0, out_file, 1);199             // End Output some information200 201             // 查找编码器202             AVCodec pCodec = avcodec_find_encoder(pCodecCtx.codec_id());203             if (pCodec == null) {// codec not found204                 return -1;205             }206             // 设置pCodecCtx的解码器为pCodec207             if (avcodec_open2(pCodecCtx, pCodec, avd) < 0) {208                 System.err.println("Could not open codec.");209                 av_dict_free(avd);210                 return -1;211             }212 213             // Write Header214             avformat_write_header(pFormatCtx, (PointerPointer
       
        ) null);215 216             // 给AVPacket分配足够大的空间217             pkt = new AVPacket();218             int yuvSize = ((width * height) / 2) * 3;219             if (av_new_packet(pkt, yuvSize) < 0) {220                 return -1;221             }222 223             int[] got_picture = { 0 };224             // encode225 226             if (avcodec_encode_video2(pCodecCtx, pkt, pFrame, got_picture) >= 0) {227                 System.out.println("got_picture[0]:" + got_picture[0]);228                 if (got_picture[0] == 1) {229                     // flush230                     BytePointer pkt_data = pkt.data();231                     // 输出pkt数据到文件232                     for (int i = 0; i < pkt.size(); i++) {233                         myByteArrayOutputStream.write(pkt_data.get(i));234                     }235                     if (myByteArrayOutputStream.size() == pkt.size()) {236                         File file = new File("C://Users//user//Desktop//test//success.h264");237                         if (!file.exists()) {238                             file.createNewFile();239                         }240                         FileOutputStream fe = new FileOutputStream(file, true);241                         fe.write(myByteArrayOutputStream.toByteArray());242                         fe.flush();243                         fe.close();244                         myByteArrayOutputStream.reset();245                     }246 247                     if ((ret = av_write_frame(pFormatCtx, pkt)) >= 0) {248                         // Write Trailer249                         if (av_write_trailer(pFormatCtx) >= 0) {250                             System.err.println("->>> Encode Successful.   pkt.size():" + pkt.size());251                         } else {252                             System.err.println("Encode failed.");253                         }254                     }255                 }256             }257             return ret;258             // 结束时销毁259         } finally {260             if (pkt != null) {261                 av_free_packet(pkt);262             }263             if (pAVStream != null) {264                 avcodec_close(pAVStream.codec());265             }266             if (pFormatCtx != null) {267                 avio_close(pFormatCtx.pb());268                 avformat_free_context(pFormatCtx);269             }270         }271     }272 273     public static byte[] conver(ByteBuffer byteBuffer) {274         int len = byteBuffer.limit() - byteBuffer.position();275         byte[] bytes = new byte[len];276 277         if (byteBuffer.isReadOnly()) {278             return null;279         } else {280             byteBuffer.get(bytes);281         }282         return bytes;283     }284 285     public static String byteToHex(byte b) {286         String hex = Integer.toHexString(b & 0xFF);287         if (hex.length() < 2) {288             hex = "0" + hex;289         }290         return hex;291     }292 293     public static void main(String[] args) {294         NewTest test = new NewTest();295     }296 297 }
       
      

 

因为在网上很少有用javacv来解码的例子，只能自己踩坑前行，一点点的测试，所以可能有很多错误或可以优化的地方。

自己项目中用到，以此来记录，便于以后再遇到相同的问题。