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<TITLE>Creating a Buffered Image (Java Developers Almanac Example)
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<META CONTENT="Patrick Chan" NAME="AUTHOR">
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<h1>The Java Developers Almanac 1.4</h1>
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<A HREF="../java.awt.image/pkg.html">java.awt.image</A><font color="#666666" class="xsmall-font">
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<B><A HREF="../java.awt.image/pkg.html#Buffered Images">Buffered Images</A></B><font color="#666666" class="xsmall-font">
[7 examples]
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<h3>e666. Creating a Buffered Image</h3>
A buffered image is a type of image whose pixels can be modified. For
example, you can draw on a buffered image and then draw the resulting
buffered image on the screen or save it to a file. A buffered image
supports many formats for storing pixels. Although a buffered image of
any format can be drawn on the screen, it is best to choose a format
that is the most compatible with the screen to allow efficient
drawing. This example demonstrates several ways of creating a
buffered image.
<P> If the buffered image will not be drawn, it can simply be
constructed with a specific format; <code>TYPE_INT_RGB</code> and
<code>TYPE_INT_ARGB</code> are typically used. See <code>BufferedImage</code> for a
list of available formats.
<P> See also <a href="../java.awt.image/Image2Buf.html" class="eglink"><b>e667</b> Creating a Buffered Image from an Image</a>.
<pre> int width = <font color="#0066ff"><i>100</i></font>;
int height = <font color="#0066ff"><i>100</i></font>;
// Create buffered image that does not support transparency
BufferedImage bimage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
// Create a buffered image that supports transparency
bimage = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
</pre>
These examples create buffered images that are compatible with the screen:
<pre> GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice gs = ge.getDefaultScreenDevice();
GraphicsConfiguration gc = gs.getDefaultConfiguration();
// Create an image that does not support transparency
bimage = gc.createCompatibleImage(width, height, Transparency.OPAQUE);
// Create an image that supports transparent pixels
bimage = gc.createCompatibleImage(width, height, Transparency.BITMASK);
// Create an image that supports arbitrary levels of transparency
bimage = gc.createCompatibleImage(width, height, Transparency.TRANSLUCENT);
</pre>
A screen compatible buffered image can also be created from a graphics context:
<pre> public void paint(Graphics g) {
Graphics2D g2d = (Graphics2D)g;
int width = <font color="#0066ff"><i>100</i></font>;
int height = <font color="#0066ff"><i>100</i></font>;
// Create an image that does not support transparency
BufferedImage bimage = g2d.getDeviceConfiguration().createCompatibleImage(
width, height, Transparency.OPAQUE);
// Create an image that supports transparent pixels
bimage = g2d.getDeviceConfiguration().createCompatibleImage(
width, height, Transparency.BITMASK);
// Create an image that supports arbitrary levels of transparency
bimage = g2d.getDeviceConfiguration().createCompatibleImage(
width, height, Transparency.TRANSLUCENT);
}
</pre>
One last way of creating a buffered image is using
<code>Component.createImage()</code>. This method can be used only if the
component is visible on the screen. Also, this method returns
buffered images that do not support transparent pixels.
<pre> BufferedImage bimage = (BufferedImage)<font color="#0066ff"><i>component</i></font>.createImage(width, height);
if (bimage == null) {
// The component is not visible on the screen
}
</pre>
<P><table width="600" CELLSPACING="0" CELLPADDING="2" BORDER="0">
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<b>Related Examples</b></font></td>
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e667. <a class="eglink" href="Image2Buf.html?l=rel">
Creating a Buffered Image from an Image
</a>
<br>
e668. <a class="eglink" href="Mandelbrot2.html?l=rel">
Creating a Buffered Image from an Array of Color-Indexed Pixel Values
</a>
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e669. <a class="eglink" href="DrawOnImage.html?l=rel">
Drawing on a Buffered Image
</a>
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e670. <a class="eglink" href="Buf2Image.html?l=rel">
Converting a Buffered Image to an Image
</a>
<br>
e671. <a class="eglink" href="ImagePixel.html?l=rel">
Getting and Setting Pixels in a Buffered Image
</a>
<br>
e672. <a class="eglink" href="CreateTxImage.html?l=rel">
Scaling, Shearing, Translating, and Rotating a Buffered Image
</a>
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See also:
<a class="eglink" href="/egs/java.awt.image/pkg.html?l=rel#Effects">
Effects
</a>
<a class="eglink" href="/egs/java.awt.image/pkg.html?l=rel#Images">
Images
</a>
<a class="eglink" href="/egs/java.awt.image/pkg.html?l=rel#Volatile%20Images">
Volatile Images
</a>
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