java实现flv转mp4/视频格式转换

• 引言

今天在开发过程中，突然遇到给前端flv格式视频还播放不了，flv在开发印象中就是跟mp4格式差不多，本地静态视频资源，怎么还就播放不了，为此只能特别做下视频转换。

• How to do

1.提前引入包

        <!--视频多媒体工具包 包含 FFmpeg、OpenCV-->
        <dependency>
            <groupId>org.bytedeco</groupId>
            <artifactId>javacv-platform</artifactId>
            <version>1.5.3</version>
        </dependency>

2.逻辑实现

    /**
     * flv转mp4
     *
     * @param inputFile  flv地址
     * @param outputFile mp4地址
     * @throws IOException
     * @throws InterruptedException
     */
    public static void flv2Mp4(String inputFile, String outputFile) throws IOException{
        long start = System.currentTimeMillis();
        FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(inputFile);
        grabber.start();
        FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(outputFile, grabber.getImageWidth(), grabber.getImageHeight());
        recorder.setVideoCodec(avcodec.AV_CODEC_ID_H264);
        recorder.setFrameRate(grabber.getFrameRate());
        recorder.start();
        Frame frame;
        while ((frame = grabber.grabFrame()) != null) {
            recorder.record(frame);
        }
        recorder.stop();
        grabber.stop();
        log.info("flv转mp4 占用时长(毫秒): {} ", (System.currentTimeMillis() - start));
    }