为什么IIOImageException java显示

Question

什么是javax.imageio.IIOException: Sample size must be <= 8的原因。 我试着写这样的图像

public static byte[] compressImage(BufferedImage imageSource, float quality) throws IOException {
    Iterator i = ImageIO.getImageWritersByFormatName("jpeg");

    ImageWriter writer = (ImageWriter) i.next();
    ImageWriteParam iwp = writer.getDefaultWriteParam();
    iwp.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
    iwp.setCompressionQuality(quality);

    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    ImageOutputStream output = ImageIO.createImageOutputStream(bos);
    writer.setOutput(output);
    IIOImage image = new IIOImage(imageSource, null, null); 
    writer.write(null, image, iwp);
    writer.dispose();

    return bos.toByteArray();
}

但是当ImageWriter尝试写入IIOImage时，出现了异常。我不知道出了什么问题，但是如果图像大小太大，也没有例外，显示和运行都很完美，但是如果图像大小太小，则会显示javax.imageio.IIOException: Sample size must be <= 8。很抱歉我的英语不好，谢谢你对我问题的回答。哦，这是完整的痕迹

Caused by: javax.imageio.IIOException: Sample size must be <= 8
at com.sun.imageio.plugins.jpeg.JPEGImageWriter.writeOnThread(JPEGImageWriter.java:494) ~[na:1.7.0_21]
at com.sun.imageio.plugins.jpeg.JPEGImageWriter.write(JPEGImageWriter.java:360) ~[na:1.7.0_21]
at com.daksa.cms.util.ImageCompressor.compressImage(ImageCompressor.java:37) ~[CmsServer-ejb_jar/:na]
at com.daksa.cms.util.ImageCompressor.compressImageToSize(ImageCompressor.java:47) ~[CmsServer-ejb_jar/:na]
at com.daksa.cms.bean.PersoEventBean.resizeImage(PersoEventBean.java:292) ~[CmsServer-ejb_jar/:na]
... 85 common frames omitted

Answer 1

也许你应该使用

com.sun.media.imageioimpl.plugins.jpeg.CLibJPEGImageWriter

类来渲染图像。请参见链接。您还可以查看以下内容：

1. http://www.codingtiger.com/questions/java/ImageIO-not-able-to-write-a-JPEG-file.html
2. ImageIO not able to write a JPEG file

Answer 2

我知道我知道这个问题，我很抱歉图像格式是错误的，它应该是。jpg