（直播、监控）利用javacv解析rtsp流，转换为flv流，通过前端flv.js解析播放

前情提要：之前利用websocket解析过https://blog.csdn.net/IT_CREATE/article/details/105625858?spm=1001.2014.3001.5501，不过由于是处理图片帧的方式，导致前端不能播放声音，同时多开窗口分流后影响了图片的刷新率，所以改用当前方式进行解析，效率得到了提高，同时更加合理
展示效果：

码云地址：https://gitee.com/dxl96/video-service

1、首先我们需要引入相关的jar包，javacv相关

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository --> 
    </parent>
    <groupId>com.de</groupId>
    <artifactId>videoservice</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>videoservice</name>
    <description>视频服务</description>

    <properties>
        <java.version>1.8</java.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <commons.io.version>2.5</commons.io.version>
        <commons.fileupload.version>1.3.3</commons.fileupload.version>
        <hutool.version>4.6.4</hutool.version>
        <fastjson.version>1.2.47</fastjson.version>
        <lang3.version>3.9</lang3.version>
        <jsckson.version>2.10.3</jsckson.version>
        <javacv.version>1.5.1</javacv.version> 
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-websocket</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>${commons.io.version}</version>
        </dependency>
        <!--文件上传工具类 -->
        <dependency>
            <groupId>commons-fileupload</groupId>
            <artifactId>commons-fileupload</artifactId>
            <version>${commons.fileupload.version}</version>
        </dependency>
        <!-- 阿里JSON解析器 -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>${fastjson.version}</version>
        </dependency>
        <!--好用的工具集-->
        <dependency>
            <groupId>