SpringBoot集成FFmpeg实现生成图片预览图与缩略图

    <profiles>
        <profile>
            <id>local</id>
            <properties>
                <profiles.active>local</profiles.active>
                <!--根据环境进行切换-->
                <ffmpeg.classifier>windows-x86_64</ffmpeg.classifier>
<!--                <ffmpeg.classifier>linux-x86_64</ffmpeg.classifier>-->
            </properties>
        </profile>
    </profiles> 

        <!-- javacv+javacpp核心库-->
        <dependency>
            <groupId>org.bytedeco</groupId>
            <artifactId>javacv</artifactId>
            <version>${javacv.version}</version>
        </dependency>
        <dependency>
            <groupId>org.bytedeco</groupId>
            <artifactId>javacpp-platform</artifactId>
            <version>${javacv.version}</version>
        </dependency>

        <!-- ffmpeg最小依赖包，必须包含上面的javacv+javacpp核心库 -->
        <dependency>
            <groupId>org.bytedeco</groupId>
            <artifactId>ffmpeg</artifactId>
            <version>5.1.2-${javacv.version}</version>
            <classifier>${ffmpeg.classifier}</classifier>
        </dependency>
        <dependency>
            <groupId>org.bytedeco</groupId>
            <artifactId>javacpp</artifactId>
            <version>${javacv.version}</version>
            <classifier>${ffmpeg.classifier}</classifier>
        </dependency>
        <dependency>
            <groupId>org.bytedeco</groupId>
            <artifactId>openblas</artifactId>
            <version>0.3.21-${javacv.version}</version>
            <classifier>${ffmpeg.classifier}</classifier>
        </dependency>
        <dependency>
            <groupId>org.bytedeco</groupId>
            <artifactId>opencv</artifactId>
            <version>4.6.0-${javacv.version}</version>
            <classifier>${ffmpeg.classifier}</classifier>
        </dependency>

package xxxx;

import cn.hutool.core.io.FileUtil;
import cn.hutool.core.io.IoUtil;
import cn.hutool.core.lang.UUID;
import lombok.extern.slf4j.Slf4j;
import org.bytedeco.javacv.FFmpegFrameRecorder;
import org.bytedeco.javacv.Frame;
import org.bytedeco.javacv.Java2DFrameConverter;
import org.springframework.stereotype.Component;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;

/**
 * 图片预览图处理器
 *
 * @author god_cvz
 */
@Component
@Slf4j
public class PicturePreviewProcessor {

    /**
     * 异步执行，防止阻碍主流程，建议使用线程池
     *
     * @param pictureUrl
     */
    public void asyncProcess(String pictureUrl) {
        new Thread(() -> process(pictureUrl)).start();
    }

    public void process(String pictureUrl) {
        log.info("开始处理照片 pictureUrl: {}", pictureUrl);
        try (InputStream inputStream = getInputStreamFromUrl(pictureUrl)) {
            // 安全地重置一个输入流以重新读取图像数据，若流不支持重置，则从网络重新下载图像‌，确保图像处理流程的可靠性
            if (inputStream.markSupported()) {
                // 将流指针归位，复用原流，避免重复下载，提升效率与节省带宽
                inputStream.reset();
                processImage(inputStream);
            } else {
                try (InputStream newInputStream = getInputStreamFromUrl(pictureUrl)) {
                    processImage(newInputStream);
                }
            }
        } catch (Exception e) {
            log.error("处理照片失败: {}", e.getMessage());
        }
    }

    /**
     * 从指定 URL 下载资源并返回 InputStream
     *
     * @param urlString 资源的 URL 地址
     * @return InputStream （需要调用方手动关闭）
     * @throws IOException 下载或连接失败时抛出异常
     */
    public InputStream getInputStreamFromUrl(String urlString) throws Exception {
        if (urlString == null || urlString.isEmpty()) {
            throw new IllegalArgumentException("URL 不能为空");
        }
        log.info("[DownloadUtils] 开始下载文件：{}", urlString);
        long startTime = System.currentTimeMillis();

        try {
            URL url = new URL(urlString);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setRequestMethod("GET");
            connection.setConnectTimeout(10_000);
            connection.setReadTimeout(15_000);
            connection.setDoInput(true);
            // 检查响应码
            int responseCode = connection.getResponseCode();
            if (responseCode != HttpURLConnection.HTTP_OK) {
                throw new IOException("下载失败，HTTP 响应码：" + responseCode);
            }
            log.info("[DownloadUtils] 连接成功[{}]，开始接收数据...", url);
            InputStream inputStream = connection.getInputStream();
            long endTime = System.currentTimeMillis();
            log.info("[DownloadUtils] 下载完成，用时 {} ms", (endTime - startTime));
            return inputStream;
        } catch (Exception e) {
            log.error("[DownloadUtils] 下载文件失败[{}], error:{}", urlString, e.getMessage());
            throw new Exception("[DownloadUtils] 下载文件失败: " + e.getMessage());
        }
    }

    private void processImage(InputStream inputStream) throws IOException {
        BufferedImage sourceImage = ImageIO.read(inputStream);
        // 生成预览图
        generatePreview(sourceImage);
        // 生成缩略图
        generateThumbnail(sourceImage);
        // 生成webp缩略图
        generateWebp(sourceImage);
    }

    private void generatePreview(BufferedImage sourceImage) {
        // 预览图宽度
        int previewWidth = 720;
        // 预览图高度
        int previewHeight = 540;
        String previewFileName = UUID.randomUUID() + ".jpg";
        String objectKey = "/bucket/preview/" + previewFileName;
        uploadImage(sourceImage, previewWidth, previewHeight, objectKey, previewFileName);
    }

    private void generateThumbnail(BufferedImage sourceImage) {
        // 缩略图宽度
        int thumbnailWidth = 200;
        // 缩略图高度
        int thumbnailHeight = 150;
        String thumbnailFileName = UUID.randomUUID() + ".jpg";
        String objectKey = "/bucket/thumbnail/" + thumbnailFileName;
        uploadImage(sourceImage, thumbnailWidth, thumbnailHeight, objectKey, thumbnailFileName);
    }

    private void uploadImage(BufferedImage sourceImage, Integer targetWith, Integer targetHeight, String objectKey, String fileName) {
        File outputFile = new File(fileName);
        FileInputStream fileInputStream = null;
        try {
            int[] changeSize = this.getChangeSize(sourceImage.getWidth(), sourceImage.getHeight(), targetWith, targetHeight);
            // 创建目标文件缓冲区
            BufferedImage outputImage = this.resizeImage(sourceImage, changeSize[0], changeSize[1]);
            // 保存图片到文件
            ImageIO.write(outputImage, "jpg", outputFile);
            fileInputStream = new FileInputStream(outputFile);
            // 上传至oss
            this.uploadFile(fileInputStream, objectKey);
            log.info("生成图片成功: objectKey: {}", objectKey);
        } catch (Exception e) {
            log.error("生成图片失败: objectKey: {}, 原因: {}", objectKey, e.getMessage());
        } finally {
            IoUtil.closeIfPosible(fileInputStream);
            FileUtil.del(outputFile);
        }
    }

    /**
     * 计算图像 按比例缩放后的宽高
     * 选择宽高缩放后较大的一边，固定其长度，另一边按原图比例缩放
     *
     * @param originalWidth  图像原宽度
     * @param originalHeight 图像原长度
     * @param targetWidth    目标宽度
     * @param targetHeight   目标高度
     * @return int[]
     */
    public int[] getChangeSize(int originalWidth, int originalHeight, int targetWidth, int targetHeight) {
        // 设置缩放比例
        double scale = Math.min(targetWidth / (double) originalWidth, targetHeight / (double) originalHeight);
        // 计算缩放后的宽高
        return new int[]{(int) (originalWidth * scale), (int) (originalHeight * scale)};
    }

    /**
     * 修改图片尺寸
     *
     * @param originImage  原图文件
     * @param targetWidth  目标宽度
     * @param targetHeight 目标高度
     * @return 制定尺寸图片
     */
    public BufferedImage resizeImage(BufferedImage originImage, int targetWidth, int targetHeight) {
        BufferedImage resizedImage = new BufferedImage(targetWidth, targetHeight, BufferedImage.TYPE_INT_RGB);
        Graphics2D graphics = resizedImage.createGraphics();
        graphics.drawImage(originImage, 0, 0, targetWidth, targetHeight, null);
        graphics.dispose();
        return resizedImage;
    }

    /**
     * todo:自定义上传至OSS文件存储服务器
     *
     * @param fileInputStream 文件流
     * @param objectKey       OSS存储key
     */
    private void uploadFile(FileInputStream fileInputStream, String objectKey) {

    }

    private void generateWebp(BufferedImage sourceImage) {
        String webpFileName = UUID.randomUUID() + ".webp";
        String objectKey = "/bucket/webp/" + webpFileName;
        uploadWebp(sourceImage, objectKey, webpFileName);
    }

    private void uploadWebp(BufferedImage sourceImage, String objectKey, String filename) {
        // 将BufferedImage转换为Frame
        Java2DFrameConverter converter = new Java2DFrameConverter();
        Frame frame = converter.convert(sourceImage);
        File outputFile = new File(filename);
        FileInputStream inputStream = null;
        // 设置输出图像的参数
        try (FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(outputFile, frame.imageWidth, frame.imageHeight)) {
            recorder.setFormat("webp");
            // 记录frame
            recorder.start();
            recorder.record(frame);
            recorder.stop();
            inputStream = new FileInputStream(outputFile);
            this.uploadFile(inputStream, objectKey);
            log.info("生成webp成功: objectKey: {}", objectKey);
        } catch (Exception | Error e) {
            log.error("生成webp失败: objectKey: {} - 原因: {}", objectKey, e.getMessage());
        } finally {
            IoUtil.closeIfPosible(inputStream);
            IoUtil.closeIfPosible(converter);
            FileUtil.del(outputFile);
        }
    }
}