alpha channel : Java Glossary

The combined ARGB value consists of the alpha component in bits 24-31, the red component in bits 16-23, the green component in bits 8-15 and the blue component in bits 0-7 where bit 0 is the least significant bit.

// Creating a colour with an alpha component.
// Note order of parameters is RGBA, not ARGB as they are internally.
// Dark orange is #ff8c00 in HTML.
Color almostTransparentDarkOrange
= new Color( 0xff /* red */,
             0x8c /* green */,
             0x00 /* blue */,
             0x1f /* alpha */ );

In the Masker Applet, I create an image, an email address painted on a transparent background, defined with alpha=0, then write the whole thing to a *.png image file on disk.

AlphaComponsite

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