FULL PRODUCT VERSION :
java version " 1.7.0_25 "
Java(TM) SE Runtime Environment (build 1.7.0_25-b16)
Java HotSpot(TM) Client VM (build 23.25-b01, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
Drawing speed has dropped dramatically due to a change in determining BufferedImage 'type'. Starting with 7u25, custom subclasses of ColorModel (et al) always produce BufferedImage type = TYPE_CUSTOM due to the addition of method BufferedImage.isStandard(). Prior to 7u25, type could be set to a value that resulted in optimized blit operations, e.g. TYPE_INT_RGB.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run the given sample application against both 7u21 and 7u25.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
BufferedImage types should be the same, and drawing rates should be similar.
ACTUAL -
7u21: BufferedImage type is TYPE_INT_RGB, drawing rate is ~160 fps.
7u25: BufferedImage type is TYPE_CUSTOM, drawing rate is ~40 fps.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package com.attachmate.example;

import javax.swing.*;
import java.awt.*;
import java.awt.color.ColorSpace;
import java.awt.image.*;
import java.lang.reflect.InvocationTargetException;
import java.util.concurrent.TimeUnit;

/**
 * Demonstrates poor drawing performance starting with Java 7u25.
 */
public class DrawImageDemo
{
    static class CustomColorModel extends DirectColorModel
    {
        public CustomColorModel(int bits, int rmask, int gmask, int bmask, int amask, boolean isAlphaPremultiplied)
        {
            super(ColorSpace.getInstance(ColorSpace.CS_sRGB),
                  bits,
                  rmask,
                  gmask,
                  bmask,
                  amask,
                  isAlphaPremultiplied,
                  DataBuffer.TYPE_INT
            );
        }
    }

    public static void main(String[] args) throws InvocationTargetException, InterruptedException
    {
        new DrawImageDemo().run();
    }

    private void run() throws InvocationTargetException, InterruptedException
    {
        final int width = 600;
        final int height = 600;
        final int redMask = 0x00ff0000;
        final int grnMask = 0x0000ff00;
        final int bluMask = 0x000000ff;
        final boolean isPremultipliedAlpha = false;

        final SampleModel sampleModel = new SinglePixelPackedSampleModel(
                DataBuffer.TYPE_INT, width, height, width, new int[]{redMask, grnMask, bluMask} );

        final BufferedImage image = new BufferedImage(new CustomColorModel(24, redMask, grnMask, bluMask, 0, isPremultipliedAlpha),
                                                      Raster.createWritableRaster(sampleModel, null),
                                                      isPremultipliedAlpha,
                                                      null );

        System.out.println( " BufferedImage type = " + image.getType() + " (expecting TYPE_INT_RGB = " + BufferedImage.TYPE_INT_RGB + ')');

        final JFrame frame = new JFrame( " Demo " );
        final JPanel panel = new JPanel() {
            protected void paintComponent(Graphics g)
            {
                super.paintComponent(g);
                synchronized (image) { ((Graphics2D) g).drawImage(image, null, null); }
            }
        };
        SwingUtilities.invokeLater(new Runnable() {
            public void run()
            {
                panel.setPreferredSize(new Dimension(width, height));
                frame.getContentPane().add(panel);
                frame.pack();
                frame.setVisible(true);
            }
        });

        final Graphics2D drawingG2d = image.createGraphics();
        final long endTime = milliTime() + TimeUnit.MILLISECONDS.convert(10, TimeUnit.SECONDS);
        int frames = 0;
        while(milliTime() < endTime)
        {
            final Color paintColor = (frames % 2 == 0) ? Color.GREEN : Color.BLUE;
            synchronized (image)
            {
                drawingG2d.setPaint(paintColor);
                drawingG2d.fillRect(0, 0, width, height);
            }
            SwingUtilities.invokeAndWait( new Runnable() {
                public void run()
                {
                    panel.paintImmediately(0, 0, width, height);
                }
            });
            ++frames;
        }
        drawingG2d.dispose();

        SwingUtilities.invokeLater( new Runnable() {
            public void run()
            {
                frame.setVisible(false);
                frame.dispose();
            }
        });

        System.out.println( " Draw rate = " + (frames / 10) + " fps " );
    }

    private long milliTime()
    {
        return TimeUnit.MILLISECONDS.convert(System.nanoTime(), TimeUnit.NANOSECONDS);
    }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Loading ColorModel subclasses via the bootclasspath may work around the problem. This may be problematic for Web Start, however.