I have a J2EE application that will receive images from a file upload page, and I need to be able to resize the images into a standard size when I display them in another page (e.g. height=125 and width=125).

I know of some PHP methods to do this, but what are some ways to do it in Java?

Thanks for the help,

how about Google

I ended up using the built-in javax.imageid.ImageIO object to handle the scaling.

Here's my processing function:

 
public static InputStream scaleImage(InputStream p_image, int p_width, int p_height) throws Exception {
 
     InputStream imageStream = new BufferedInputStream(p_image);
     Image image = (Image) ImageIO.read(imageStream); 
 
     int thumbWidth = p_width;
        int thumbHeight = p_height;        
 
        // Make sure the aspect ratio is maintained, so the image is not skewed
        double thumbRatio = (double)thumbWidth / (double)thumbHeight;
        int imageWidth = image.getWidth(null);
        int imageHeight = image.getHeight(null);
        double imageRatio = (double)imageWidth / (double)imageHeight;
        if (thumbRatio < imageRatio) {
          thumbHeight = (int)(thumbWidth / imageRatio);
        } else {
          thumbWidth = (int)(thumbHeight * imageRatio);
        }
 
        // Draw the scaled image
        BufferedImage thumbImage = new BufferedImage(thumbWidth, 
          thumbHeight, BufferedImage.TYPE_INT_RGB);
        Graphics2D graphics2D = thumbImage.createGraphics();
        graphics2D.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
          RenderingHints.VALUE_INTERPOLATION_BILINEAR);
        graphics2D.drawImage(image, 0, 0, thumbWidth, thumbHeight, null);
 
        // Write the scaled image to the outputstream
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
        JPEGEncodeParam param = encoder.
          getDefaultJPEGEncodeParam(thumbImage);
        int quality = 100; // Use between 1 and 100, with 100 being highest quality
        quality = Math.max(0, Math.min(quality, 100));
        param.setQuality((float)quality / 100.0f, false);
        encoder.setJPEGEncodeParam(param);
        encoder.encode(thumbImage);        
        ImageIO.write(thumbImage, IMAGE_JPG , out); 
 
        // Read the outputstream into the inputstream for the return value
        ByteArrayInputStream bis = new ByteArrayInputStream(out.toByteArray());        
 
        return bis;        
    }

I'm using Struts for the file upload part (where the user submits the photo image from a web page). A FormFile has a getInputStream method that is used to pass the photo's inputstream to the scaleImage() mothod above.

Assuming that you've set up a Struts form with a photo property, then you'd use the following code in the StrutsAction to access the uploaded photo's inputstream:

 
FormFile image = strutsForm.getPhoto();
if (image != null && image.getFileSize() > 0) { 
   // This returns an inputstream which you can save to your database or write to a file  
   ImageUtil.scaleImage(strutsForm.getPhoto().getInputStream(), 500, 500)));  
}

Hello,

This code works perfect!!

I have only one question. If I want to save my file to the database I first use newCV.setBinaryContent(fileItem.getInputStream(),f ileItem.getSize()); to set the binary content where fileItem is the file returned from my Form. For the resize I use you code, but then I need to know the size after the resize. How do I get that.

Thx

Mike

Yes there are a few Java based library like JAI and the sample code from RickPl is a fine example. But, I find the quality of resizing images is bad with large image.

So I suggest you can try calling unix pipe with ImageMagick to do image resizing. Check out the code here. You will find the quality by ImageMagick would be a lot better! But it is slightly more difficult to setup the Imagemagick properly.... good luck

Originally Posted by duyve028

I have only one question. If I want to save my file to the database I first use newCV.setBinaryContent(fileItem.getInputStream(),f ileItem.getSize()); to set the binary content where fileItem is the file returned from my Form. For the resize I use you code, but then I need to know the size after the resize. How do I get that.

I'm not sure how to do what you're asking with PHP + MySQL. But, as a suggestion, you might consider saving the resized image to the file system, and then only storing the filename in the database.

With SQL Server you'll get far better performance this way, moreso the more images you add. A database engine is typically optimized for smaller, more structured types of data, and lots of BLOB data can interfere with the rdbms cache.

hi rick : thanks your code.It help us alot ^_^

Glad to help!

Don't use bilinear though, I read bicubic is much better.

hi,
the code given by Rick works for images whose height and width are greater than p_height and p_width respectively. When an image whose height and width is less than p_height and p_width, problem occurs.

I tried to check the height and width, and if the the original image's height and width are less than p_height and p_width, then just return the fileInputStream. but there is some problem.

I am downloading and displaying the image after scaling and uploading, but the is some problem with smaller images as i said .

http://www.comesolvego.com/2008/04/2...king-solution/