JavaCV 实现视频转码

查询了网上很多资料，发现没有比较靠谱的实现，JavaCV的资料还是比较少的

安装依赖

<dependency>
  <groupId>org.bytedeco</groupId>
  <artifactId>javacv-platform</artifactId>
  <version>1.5.3</version>
</dependency>

代码实现

    /**
     * 视频转码
     */
    public static void recode() throws FrameGrabber.Exception, FrameRecorder.Exception {
        String filePath = "ef568e9b96be750fba2e918b651aa70c.avi";
        String ext = filePath.substring(filePath.lastIndexOf("."));
        String newFilePath = filePath.replace(ext, "_recode.mp4");
        FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(filePath);
        grabber.start();
        FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(newFilePath, grabber.getImageWidth(),
            grabber.getImageHeight(), grabber.getAudioChannels());
        recorder.setVideoCodec(avcodec.AV_CODEC_ID_H264);
        recorder.setFormat("mp4");
        recorder.setPixelFormat(avutil.AV_PIX_FMT_YUV420P);
        recorder.setFrameRate(grabber.getFrameRate());
        int bitrate = grabber.getVideoBitrate();
        if (bitrate == 0) {
            bitrate = grabber.getAudioBitrate();
        }
        recorder.setVideoBitrate(bitrate);
        recorder.start(grabber.getFormatContext());
        AVPacket packet;
        long dts = 0;
        while ((packet = grabber.grabPacket()) != null) {
            long currentDts = packet.dts();
            if (currentDts >= dts) {
                recorder.recordPacket(packet);
            }
            dts = currentDts;
        }
        recorder.stop();
        recorder.release();
        grabber.stop();
    }