Java实现视频格式转换的完整指南：从FFmpeg到纯Java方案！

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class VideoFormatConverter {

    public static void convertVideo(String inputPath, String outputPath, String format) throws IOException, InterruptedException {
        // 构建FFmpeg命令
        String command = String.format("ffmpeg -i %s -c:v libx264 -c:a aac %s.%s", inputPath, outputPath, format);

        // 使用ProcessBuilder执行命令
        ProcessBuilder processBuilder = new ProcessBuilder(command.split(" "));
        processBuilder.redirectErrorStream(true);
        Process process = processBuilder.start();

        // 获取FFmpeg的输出信息
        BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
        String line;
        while ((line = reader.readLine()) != null) {
            System.out.println(line);
        }

        // 等待进程结束
        int exitCode = process.waitFor();
        if (exitCode == 0) {
            System.out.println("视频转换成功！");
        } else {
            System.out.println("视频转换失败！");
        }
    }

    public static void main(String[] args) {
        try {
            String inputPath = "input.mp4";  // 输入视频文件路径
            String outputPath = "output";    // 输出视频文件路径（不包含扩展名）
            String format = "avi";          // 目标视频格式
            convertVideo(inputPath, outputPath, format);
        } catch (IOException | InterruptedException e) {
            e.printStackTrace();
        }
    }
}

<dependency>
    <groupId>com.github.kokorin.jaffree</groupId>
    <artifactId>jaffree</artifactId>
    <version>2023.01.01</version>
</dependency>

import com.github.kokorin.jaffree.ffmpeg.FFmpeg;
import com.github.kokorin.jaffree.ffmpeg.FFmpegResult;

import java.nio.file.Path;
import java.nio.file.Paths;

public class JaffreeVideoConverter {

    public static void main(String[] args) {
        // 输入和输出文件路径
        Path input = Paths.get("input.mp4");
        Path output = Paths.get("output.avi");

        // 调用FFmpeg进行视频格式转换
        FFmpegResult result = FFmpeg.atPath()
                .addInput(input.toString())
                .addOutput(output.toString())
                .execute();

        System.out.println("视频格式转换完成！");
    }
}

import com.xuggle.mediatool.IMediaReader;
import com.xuggle.mediatool.IMediaWriter;
import com.xuggle.mediatool.ToolFactory;

public class XuggleVideoConverter {

    public static void main(String[] args) {
        String inputFile = "input.mp4";
        String outputFile = "output.avi";

        // 创建媒体读取器和写入器
        IMediaReader reader = ToolFactory.makeReader(inputFile);
        IMediaWriter writer = ToolFactory.makeWriter(outputFile, reader);

        // 将读取器与写入器关联
        reader.addListener(writer);

        // 开始处理
        while (reader.readPacket() == null) {
            // 持续读取数据包
        }

        System.out.println("视频转换完成！");
    }
}

<dependency>
    <groupId>org.jcodec</groupId>
    <artifactId>jcodec</artifactId>
    <version>0.2.5</version>
</dependency>

import org.jcodec.api.SequenceEncoder;
import org.jcodec.common.io.NIOUtils;
import org.jcodec.common.model.Picture;

import java.io.File;

public class JCodecConverter {

    public static void main(String[] args) throws Exception {
        File output = new File("output.avi");

        SequenceEncoder encoder = new SequenceEncoder(NIOUtils.writableChannel(output));
        Picture picture;

        // 假设已经读取了视频帧 (需要实现解码器读取视频帧的逻辑)
        while ((picture = getNextPicture()) != null) {
            encoder.encodeNativeFrame(picture);
        }

        encoder.finish();
        System.out.println("视频格式转换完成！");
    }

    private static Picture getNextPicture() {
        // 实现解码器逻辑，返回下一帧
        return null;
    }
}