java实现h265转h264

要将H.265转换为H.264，您需要使用编码器。以下是使用Java编写的示例代码，演示如何使用Xuggler库将H.265视频编码为H.264：

import java.awt.image.BufferedImage;
import com.xuggle.mediatool.IMediaWriter;
import com.xuggle.mediatool.ToolFactory;
import com.xuggle.xuggler.ICodec;
import com.xuggle.xuggler.IPixelFormat;
import com.xuggle.xuggler.IVideoPicture;
import com.xuggle.xuggler.IVideoResampler;

public class H265toH264Converter {

    public static void main(String[] args) {
        String inputFile = "input.h265";
        String outputFile = "output.h264";

        // create a media reader
        IMediaReader mediaReader = ToolFactory.makeReader(inputFile);

        // create a media writer
        IMediaWriter mediaWriter = ToolFactory.makeWriter(outputFile, mediaReader);

        // configure the output codec
        mediaWriter.addVideoStream(0, 0, ICodec.ID.CODEC_ID_H264, 640, 480);

        // create a video resampler to resize the input video
        IVideoResampler resampler = null;
        if (mediaReader.getContainer().getStream(0).getStreamCoder().getPixelType() != IPixelFormat.Type.YUV420P) {
            resampler = IVideoResampler.make(640, 480, IPixelFormat.Type.YUV420P,
                    mediaReader.getContainer().getStream(0).getStreamCoder().getWidth(),
                    mediaReader.getContainer().getStream(0).getStreamCoder().getHeight(),
                    mediaReader.getContainer().getStream(0).getStreamCoder().getPixelType());
        }

        // read the input video and write the output video
        mediaReader.addListener(mediaWriter);
        while (mediaReader.readPacket() == null) {
            // get the next video frame
            BufferedImage image = mediaReader.readVideoFrame();

            // resample the video frame if necessary
            if (resampler != null) {
                BufferedImage resizedImage = new BufferedImage(640, 480, BufferedImage.TYPE_3BYTE_BGR);
                resizedImage.getGraphics().drawImage(image, 0, 0, 640, 480, null);
                image = resizedImage;
            }

            // convert the video frame to an xuggle IVideoPicture
            IVideoPicture picture = IVideoPicture.make(
                    mediaWriter.getStream(0).getStreamCoder().getPixelType(), 640, 480);
            picture.getByteBuffer(0).put((byte[]) image.getData().getData());

            // encode the video frame
            mediaWriter.encodeVideo(0, picture);
        }

        // flush the media writer
        mediaWriter.flush();
    }
}

此代码使用Xuggler库读取H.265视频文件并将其转换为H.264。它还使用IVideoResampler来调整输入视频的大小，以适应H.264编码器的要求。然后，它将每个视频帧编码为H.264格式并将其写入输出文件。您需要将Xuggler库添加到类路径中，以便Java可以找到它。