Java - h.264视频编码

Question

我想制作一个程序，可以编码和解码h.264视频，所以我可以编辑这个视频。 任何人都可以告诉我如何做到这一点，如果我想在Java中做这个程序？

Answer 1

获取或编写一个可对所需格式进行编码和解码的类。确保它是一个服务提供者接口。将它添加到应用程序的运行时类路径中。使用JMF的默认播放器播放它。不太了解编辑它。

Answer 2

检查ffmpeg库和x264。编译并撰写这些库。它具有非常好的视频编码/解码API。如果你只编译ffmpeg，那么你不能编码h.264，只能解码。要编码h264，您需要编译x264库。 http://ubuntuforums.org/showthread.php?t=786095。很好的教程。 这是C API，但您可以使用本地方法调用它。

此致敬意，并对不起我的英语。

Answer 3

您可以使用JCodec（http://jcodec.org）。

要解码的视频序列中去：

int frameNumber = 10000; 
FileChannelWrapper ch = null; 
try { 
    ch = NIOUtils.readableFileChannel(new File(path to mp4)); 
    FrameGrab frameGrab = new FrameGrab(ch); 

    frameGrab.seek(frameNumber); 
    Picture frame; 
    for (int i = 0; (frame = frameGrab.getNativeFrame()) != null && i < 200; i++) { 
     // Do something 
    } 
} finally { 
    NIOUtils.closeQuietly(ch); 
} 

为了编码序列：

public class SequenceEncoder { 
    private SeekableByteChannel ch; 
    private Picture toEncode; 
    private RgbToYuv420 transform; 
    private H264Encoder encoder; 
    private ArrayList<ByteBuffer> spsList; 
    private ArrayList<ByteBuffer> ppsList; 
    private CompressedTrack outTrack; 
    private ByteBuffer _out; 
    private int frameNo; 
    private MP4Muxer muxer; 

    public SequenceEncoder(File out) throws IOException { 
     this.ch = NIOUtils.writableFileChannel(out); 

     // Transform to convert between RGB and YUV 
     transform = new RgbToYuv420(0, 0); 

     // Muxer that will store the encoded frames 
     muxer = new MP4Muxer(ch, Brand.MP4); 

     // Add video track to muxer 
     outTrack = muxer.addTrackForCompressed(TrackType.VIDEO, 25); 

     // Allocate a buffer big enough to hold output frames 
     _out = ByteBuffer.allocate(1920 * 1080 * 6); 

     // Create an instance of encoder 
     encoder = new H264Encoder(); 

     // Encoder extra data (SPS, PPS) to be stored in a special place of 
     // MP4 
     spsList = new ArrayList<ByteBuffer>(); 
     ppsList = new ArrayList<ByteBuffer>(); 

    } 

    public void encodeImage(Picture bi) throws IOException { 
     if (toEncode == null) { 
      toEncode = Picture.create(bi.getWidth(), bi.getHeight(), ColorSpace.YUV420); 
     } 

     // Perform conversion (RGB -> YUV) 
     transform.transform(bi, toEncode); 

     // Encode image into H.264 frame, the result is stored in '_out' buffer 
     _out.clear(); 
     ByteBuffer result = encoder.encodeFrame(_out, toEncode); 

     // Based on the frame above form correct MP4 packet 
     spsList.clear(); 
     ppsList.clear(); 
     H264Utils.encodeMOVPacket(result, spsList, ppsList); 

     // Add packet to video track 
     outTrack.addFrame(new MP4Packet(result, frameNo, 25, 1, frameNo, true, null, frameNo, 0)); 

     frameNo++; 
    } 

    public void finish() throws IOException { 
     // Push saved SPS/PPS to a special storage in MP4 
     outTrack.addSampleEntry(H264Utils.createMOVSampleEntry(spsList, ppsList)); 

     // Write MP4 header and finalize recording 
     muxer.writeHeader(); 
     NIOUtils.closeQuietly(ch); 
    } 
} 

终于到转换为和FROM Android的图像使用：

public static Picture fromBitmap(Bitmap src) { 
    Picture dst = Picture.create((int)src.getWidth(), (int)src.getHeight(), RGB); 
    fromBitmap(src, dst); 
    return dst; 
} 

public static void fromBitmap(Bitmap src, Picture dst) { 
    int[] dstData = dst.getPlaneData(0); 
    int[] packed = new int[src.getWidth() * src.getHeight()]; 

    src.getPixels(packed, 0, src.getWidth(), 0, 0, src.getWidth(), src.getHeight()); 

    for (int i = 0, srcOff = 0, dstOff = 0; i < src.getHeight(); i++) { 
     for (int j = 0; j < src.getWidth(); j++, srcOff++, dstOff += 3) { 
      int rgb = packed[srcOff]; 
      dstData[dstOff]  = (rgb >> 16) & 0xff; 
      dstData[dstOff + 1] = (rgb >> 8) & 0xff; 
      dstData[dstOff + 2] = rgb & 0xff; 
     } 
    } 
} 

public static Bitmap toBitmap(Picture src) { 
    Bitmap dst = Bitmap.create(pic.getWidth(), pic.getHeight(), ARGB_8888); 
    toBitmap(src, dst); 
    return dst; 
} 

public static void toBitmap(Picture src, Bitmap dst) { 
    int[] srcData = src.getPlaneData(0); 
    int[] packed = new int[src.getWidth() * src.getHeight()]; 

    for (int i = 0, dstOff = 0, srcOff = 0; i < src.getHeight(); i++) { 
     for (int j = 0; j < src.getWidth(); j++, dstOff++, srcOff += 3) { 
      packed[dstOff] = (srcData[srcOff] << 16) | (srcData[srcOff + 1] << 8) | srcData[srcOff + 2]; 
     } 
    } 
    dst.setPixels(packed, 0, src.getWidth(), 0, 0, src.getWidth(), src.getHeight()); 
} 

FINALLY解码上，你会得到YUV框架出来，以便将其转换成RGB帧去：

Transform transform = ColorUtil.getTransform(pic.getColor(), ColorSpace.RGB); 
Picture rgb = Picture.create(pic.getWidth(), pic.getHeight(), ColorSpace.RGB); 
transform.transform(pic, rgb); 

，并确保您下载JAR所有DEPS：http://jcodec.org/downloads/jcodec-0.1.3-uberjar.jar

Answer 4

有一个Java包装可用于VLC：http://www.capricasoftware.co.uk/projects/vlcj/