ffmpeg将byte[]编码，并得到编码后的byte[] java

可以使用Java中的ProcessBuilder类调用FFmpeg命令行工具来实现将byte[]编码并得到编码后的byte[]。

以下是一个示例代码：

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.StandardCharsets;

public class FFmpegEncoder {

    private static final String FFMPEG_COMMAND = "ffmpeg";
    private static final String INPUT_PIPE = "pipe:0";
    private static final String OUTPUT_PIPE = "pipe:1";
    private static final String[] ENCODING_PARAMETERS = {
            "-f", "wav",
            "-ar", "44100",
            "-ac", "2",
            "-i", INPUT_PIPE,
            "-c:a", "aac",
            "-b:a", "128k",
            "-f", "adts",
            OUTPUT_PIPE
    };

    public static byte[] encode(byte[] input) throws Exception {
        ProcessBuilder pb = new ProcessBuilder(FFMPEG_COMMAND, ENCODING_PARAMETERS);
        pb.redirectErrorStream(true);
        Process process = pb.start();

        try (InputStream inputStream = new ByteArrayInputStream(input);
             OutputStream outputStream = process.getOutputStream();
             InputStream processOutput = process.getInputStream();
             ByteArrayOutputStream resultStream = new ByteArrayOutputStream()) {

            byte[] buffer = new byte[4096];
            int bytesRead;

            // 将输入数据写入FFmpeg的stdin
            while ((bytesRead = inputStream.read(buffer)) != -1) {
                outputStream.write(buffer, 0, bytesRead);
                outputStream.flush();
            }
            outputStream.close();

            // 读取FFmpeg的stdout，即编码后的数据
            while ((bytesRead = processOutput.read(buffer)) != -1) {
                resultStream.write(buffer, 0, bytesRead);
            }

            return resultStream.toByteArray();
        }
    }

    public static void main(String[] args) throws Exception {
        String input = "Hello, world!";
        byte[] inputBytes = input.getBytes(StandardCharsets.UTF_8);

        byte[] encodedBytes = encode(inputBytes);

        System.out.println("Encoded bytes: " + encodedBytes.length);
    }
}

上述代码将输入的byte[]数据编码为AAC格式，并返回编码后的byte[]数据。你可以根据具体需求修改FFmpeg的命令行参数。