miscellaneous, etc.

What happens is that you read in an image with ImageIO, but then any kind of manipulation of the image is very slow.

 // read in the image
 BufferedImage bufferedImageOriginal = 
         ImageIO.read( bufferedinputstream );


 // get a byte output stream and wrap it in a buffered 
 //output stream
 ByteArrayOutputStream bytearrayoutputstream = 
         new ByteArrayOutputStream();
 BufferedOutputStream bufferedoutputstream = 
         new BufferedOutputStream( bytearrayoutputstream );

 // write the image to the output stream
 ImageIO.write( bufferedImageOriginal, “jpg”, 
	bufferedoutputstream );

 // get the byte array from the byte output stream
 byte[] byteData = bytearrayoutputstream.toByteArray();

 // generate the small thumbnail
 stopwatch.reset();
 stopwatch.start();
 Image imageSmall = bufferedImageOriginal.getScaledInstance( 50,
         -1,
         BufferedImage.SCALE_SMOOTH );
 BufferedImage bufferedimageSmall = convert( imageSmall );
 bytearrayoutputstream = new ByteArrayOutputStream();
 bufferedoutputstream = 
         new BufferedOutputStream( bytearrayoutputstream );
 ImageIO.write( bufferedimageSmall, “jpg”, bufferedoutputstream );
 byte[] byteDataSmall = bytearrayoutputstream.toByteArray();

The reading of the image will go very fast, but the scaling will be super slow (i.e.. 0.3s to read and 22.3 to scale).

As it so happens, this is a problem with the color space of the original image. It’s not in the sRGB color space and, as a result, it does a transform on each pixel to get it into the sRGB colorspace, [Bug ID: 4705399](http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4705399).

Forcing ImageIO to read the image in with the sRGB color space seems to solve this issue.

public static BufferedImage readImage(Object source)
	throws IOException {


	
	ImageInputStream stream = 
		ImageIO.createImageInputStream(source);
	ImageReader reader = 
		(ImageReader) ImageIO.getImageReaders(stream).next();
	reader.setInput(stream);
	ImageReadParam param = reader.getDefaultReadParam();

	
	ImageTypeSpecifier typeToUse = null;
	for (Iterator i = reader.getImageTypes(0); i.hasNext(); ) {
		ImageTypeSpecifier type = (ImageTypeSpecifier) i.next();
		if( type.getColorModel().getColorSpace().isCS_sRGB() ) {
			typeToUse = type;
		}
	}

	
	if (typeToUse!=null) param.setDestinationType(typeToUse);

	
	BufferedImage b = reader.read(0, param);

	
	reader.dispose();
	stream.close();
	return b;

}