Thumbnails java图片压缩

简介

主要利用了工具类对图片进行了循环压缩至指定大小效率不是太高

案例代码如下

• 输入输出都是byte数组，后续使用更方便

public class ImageFileCompressUtils {

    /**
     * 压缩图片
     * @param sourceBytes
     * @param quality
     * @param maxWidth
     * @param maxHeight
     * @param targetFileSize
     * @return
     * @throws Exception
     */
    public static byte[] compressImageFile(byte[] sourceBytes, double quality, Integer maxWidth, Integer maxHeight, Integer targetFileSize) throws Exception{
        BufferedImage bim = ImageIO.read(new ByteArrayInputStream(sourceBytes));
        int srcWidth = bim.getWidth();
        int srcHeight = bim.getHeight();

        //先转换成jpg
        Thumbnails.Builder builder = Thumbnails.of(new ByteArrayInputStream(sourceBytes)).outputFormat("png");

        // 指定大小（宽或高超出会才会被缩放）
        if(srcWidth > maxWidth || srcHeight > maxHeight) {
            builder.size(maxWidth, maxHeight);
        }else{
            //宽高均小，指定原大小
            builder.size(srcWidth,srcHeight);
        }
        // 写入到内存
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream(); //字节输出流（写入到内存）
        builder.toOutputStream(byteArrayOutputStream);
        return compressImageCircle(byteArrayOutputStream.toByteArray(),targetFileSize,quality);
    }

    /**
     * 压缩图片至指定大小
     * @param sourceBytes   源
     * @param targetFileSize    目标
     * @param quality   压缩比例0-1最好小于0.9
     * @return
     * @throws Exception
     */
    public static byte[] compressImageCircle(byte[] sourceBytes, long targetFileSize, double quality) throws Exception{
        long sourceFileSize = sourceBytes.length;
        // 判断大小
        if (sourceFileSize <= targetFileSize * 1024) {
            return sourceBytes;
        }
        // 计算宽高
        BufferedImage bim = ImageIO.read(new ByteArrayInputStream(sourceBytes));
        int sourceWidth = bim.getWidth();
        int sourceHeight = bim.getHeight();
        int targetWidth = new BigDecimal(sourceWidth).multiply(new BigDecimal(quality)).intValue();
        int targetHeight = new BigDecimal(sourceHeight).multiply(new BigDecimal(quality)).intValue();

        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        Thumbnails.of(new ByteArrayInputStream(sourceBytes)).size(targetWidth, targetHeight).outputQuality(quality).toOutputStream(byteArrayOutputStream);
        return compressImageCircle(byteArrayOutputStream.toByteArray(), targetFileSize, quality);
    }
}
复制代码

使用demo

@Test
    public void tt03() throws Exception{

        byte[] source = ImageFileCompressUtils.compressImageCircle(Files.readAllBytes(new File("C:\\Users\\86183\\Pictures\\20200911131241.jpg").toPath()),200,0.8);

        getFileByBytes(source,"C:\\Users\\86183\\Pictures","2222.png");
    }


    //将Byte数组转换成文件
    public static void getFileByBytes(byte[] bytes, String filePath, String fileName) {
        BufferedOutputStream bos = null;
        FileOutputStream fos = null;
        File file = null;
        try {
            File dir = new File(filePath);
            if (!dir.exists() && dir.isDirectory()) {// 判断文件目录是否存在
                dir.mkdirs();
            }
            file = new File(filePath + "\\" + fileName);
            fos = new FileOutputStream(file);
            bos = new BufferedOutputStream(fos);
            bos.write(bytes);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (bos != null) {
                try {
                    bos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (fos != null) {
                try {
                    fos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
复制代码