Java生成缩略图之Thumbnailator

最新推荐文章于 2025-05-29 14:41:35 发布

最新推荐文章于 2025-05-29 14:41:35 发布 · 452 阅读

文章标签：

#java #image #thumbnail

Java 专栏收录该内容

71 篇文章

订阅专栏

Thumbnailator是一个Java库，用于简化图片缩略图的生成过程。它支持多种操作如按比例缩放、固定尺寸缩放、旋转、加水印、裁剪等，并能输出不同格式。

[size=medium]Thumbnailator 是一个为Java界面更流畅的缩略图生成库。从API提供现有的图像文件和图像对象的缩略图中简化了缩略过程，两三行代码就能够从现有图片生成缩略图，且允许微调缩略图生成，同时保持了需要写入到最低限度的代码量。同时还支持根据一个目录批量生成缩略图。

[url=http://code.google.com/p/thumbnailator/]http://code.google.com/p/thumbnailator/[/url]

版本：thumbnailator-0.4.2.jar

原图如下：[/size]
[img]http://dl.iteye.com/upload/attachment/0068/9156/5e19ee98-3217-3c5e-8cd2-fdf613e389eb.jpg[/img]

[b]1、指定大小进行缩放[/b]


//size(宽度, 高度)

/*  
 * 若图片横比200小，高比300小，不变  
 * 若图片横比200小，高比300大，高缩小到300，图片比例不变  
 * 若图片横比200大，高比300小，横缩小到200，图片比例不变  
 * 若图片横比200大，高比300大，图片按比例缩小，横为200或高为300  
 */ 
Thumbnails.of("images/a380_1280x1024.jpg") 
        .size(200, 300)
        .toFile("c:/a380_200x300.jpg");

Thumbnails.of("images/a380_1280x1024.jpg") 
        .size(2560, 2048) 
        .toFile("c:/a380_2560x2048.jpg");

[b]2、按照比例进行缩放[/b]


//scale(比例)
Thumbnails.of("images/a380_1280x1024.jpg") 
        .scale(0.25f)
        .toFile("c:/a380_25%.jpg");

Thumbnails.of("images/a380_1280x1024.jpg") 
        .scale(1.10f)
        .toFile("c:/a380_110%.jpg");

[b]3、不按照比例，指定大小进行缩放[/b]


//keepAspectRatio(false) 默认是按照比例缩放的
Thumbnails.of("images/a380_1280x1024.jpg") 
        .size(200, 200) 
        .keepAspectRatio(false) 
        .toFile("c:/a380_200x200.jpg");

[b]4、旋转[/b]


//rotate(角度),正数：顺时针 负数：逆时针
Thumbnails.of("images/a380_1280x1024.jpg") 
		.size(1280, 1024)
        .rotate(90) 
        .toFile("c:/a380_rotate+90.jpg"); 

Thumbnails.of("images/a380_1280x1024.jpg") 
		.size(1280, 1024)
        .rotate(-90) 
        .toFile("c:/a380_rotate-90.jpg");

[img]http://dl.iteye.com/upload/attachment/0068/9164/9ed3f07a-8ec9-323b-96fd-4fc7046f9b9f.jpg[/img][img]http://dl.iteye.com/upload/attachment/0068/9166/76e561b3-f5d5-3cfb-8ef8-60f928249d4a.jpg[/img]

[b]5、水印[/b]


//watermark(位置，水印图，透明度)
Thumbnails.of("images/a380_1280x1024.jpg") 
		.size(1280, 1024)
        .watermark(Positions.BOTTOM_RIGHT, ImageIO.read(new File("images/watermark.png")), 0.5f) 
        .outputQuality(0.8f) 
        .toFile("c:/a380_watermark_bottom_right.jpg");

Thumbnails.of("images/a380_1280x1024.jpg") 
		.size(1280, 1024)
        .watermark(Positions.CENTER, ImageIO.read(new File("images/watermark.png")), 0.5f) 
        .outputQuality(0.8f) 
        .toFile("c:/a380_watermark_center.jpg");

[img]http://dl.iteye.com/upload/attachment/0068/9168/01be5a7b-73ad-3f6a-913f-54558037e30b.jpg[/img][img]http://dl.iteye.com/upload/attachment/0068/9170/1406ca7a-fb25-386f-a669-66320a164562.jpg[/img]

[b]6、裁剪[/b]


//sourceRegion()

//图片中心400*400的区域
Thumbnails.of("images/a380_1280x1024.jpg")
		.sourceRegion(Positions.CENTER, 400,400)
		.size(200, 200)
        .keepAspectRatio(false) 
        .toFile("c:/a380_region_center.jpg");

//图片右下400*400的区域
Thumbnails.of("images/a380_1280x1024.jpg")
		.sourceRegion(Positions.BOTTOM_RIGHT, 400,400)
		.size(200, 200)
        .keepAspectRatio(false) 
        .toFile("c:/a380_region_bootom_right.jpg");

//指定坐标
Thumbnails.of("images/a380_1280x1024.jpg")
		.sourceRegion(600, 500, 400, 400)
		.size(200, 200)
        .keepAspectRatio(false) 
        .toFile("c:/a380_region_coord.jpg");

[img]http://dl.iteye.com/upload/attachment/0068/9158/99372a0d-9d1e-3cc4-95e1-4e05121baac8.jpg[/img][img]http://dl.iteye.com/upload/attachment/0068/9160/abc72ae9-f3f4-34c3-a981-a78927ac4370.jpg[/img][img]http://dl.iteye.com/upload/attachment/0068/9162/62020296-43c5-3e95-8c4f-f72e2b4710c2.jpg[/img]

[b]7、转化图像格式[/b]


//outputFormat(图像格式)
Thumbnails.of("images/a380_1280x1024.jpg") 
		.size(1280, 1024)
        .outputFormat("png") 
        .toFile("c:/a380_1280x1024.png"); 

Thumbnails.of("images/a380_1280x1024.jpg") 
		.size(1280, 1024)
        .outputFormat("gif") 
        .toFile("c:/a380_1280x1024.gif");

[b]8、输出到OutputStream[/b]


//toOutputStream(流对象)
OutputStream os = new FileOutputStream("c:/a380_1280x1024_OutputStream.png");
Thumbnails.of("images/a380_1280x1024.jpg") 
		.size(1280, 1024)
        .toOutputStream(os);

[b]9、输出到BufferedImage[/b]


//asBufferedImage() 返回BufferedImage
BufferedImage thumbnail = Thumbnails.of("images/a380_1280x1024.jpg") 
		.size(1280, 1024)
		.asBufferedImage();
ImageIO.write(thumbnail, "jpg", new File("c:/a380_1280x1024_BufferedImage.jpg"));

[color=red][b]需要注意的是，对于CMYK模式的图像，由于[url=http://bugs.java.com/bugdatabase/view_bug.do?bug_id=5100094]JDK的Bug[/url]，目前还不能够处理，会出以下异常：[/b][/color]
[quote]javax.imageio.IIOException: Unsupported Image Type
at com.sun.imageio.plugins.jpeg.JPEGImageReader.readInternal(JPEGImageReader.java:1063)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.read(JPEGImageReader.java:1034)
at javax.imageio.ImageReader.read(ImageReader.java:940)
at net.coobird.thumbnailator.tasks.io.FileImageSource.read(Unknown Source)[/quote]
[quote] javax.imageio.IIOException: Incompatible color conversion
at com.sun.imageio.plugins.jpeg.JPEGImageReader.checkColorConversion(JPEGImageReader.java:973)[/quote]

ICC profile
[quote] java.lang.IllegalArgumentException: Numbers of source Raster bands and source color space components do not match
at java.awt.image.ColorConvertOp.filter(ColorConvertOp.java:482)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.acceptPixels(JPEGImageReader.java:1268)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.readImage(Native Method)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.readInternal(JPEGImageReader.java:1236)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.read(JPEGImageReader.java:1039)
at javax.imageio.ImageReader.read(ImageReader.java:939)[/quote]

这些问题可以JAI.create()来代替ImageIO.read()解决。而高清图的内存溢出OOM问题只能使用ImageMagick转换了。