Which bitmap images are supported
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Which bitmap images are supported?

If you're a developer, you generally use bitmap images to illustrate applications or websites. Photos are also saved as bitmap images of very large sizes. IconWorkshop has been optimized to work with small images. Therefore, it is intended to be used for edition of illustration images rather than large photos. If you open an image larger than 1024x1024 pixel, you'll be prompted to open it in the viewer rather than the editor.

IconWorkshop supports the following color depths in images: 32 BPP (RGB with Alpha Channel transparency), 24 BPP (RGB, simulated transparency), 8 BPP (256 colors, simulated transparency), 4 BPP (16 fixed colors, simulated transparency) and 1 BPP (Monochrome).

The Alpha Channel transparency is coded in a 8 BPP channel which permits creating smooth and variable transparent areas in images. The simulated transparency is used in images containing 24 BPP or less color depth. For these images, the transparency is coded by using a fixed color. Each pixel that have this exact color will be converted as transparent when the image is loaded in the application. Usually, the color used is a flashy green RGB(0,255,0) or magenta RGB(255,0,255). The problem of this method is that if you use a pixel of that color in your icon image (not the background), it will be converted as transparent. The other issue is the poor quality of the borders (around the icons) because it does not permit smooth transparency. In other words, a pixel is either 100% transparent or 100% opaque, there is no variable transparency. It results in "aliasing" on borders for icons with rounded shapes.

How transparency in images is handled by IconWorkshop?

In 32 BPP (RGB/A) images, the transparency is coded in the alpha channel and saved in the image itself.

As we discussed above, for 24 BPP or less color depths the transparency is coded by a specific color. IconWorkshop automatically detect this color and display the icons with a real transparency. You don't see the Green or Magenta color as coded in the image. Instead you see the chessboard texture which indicates that this is a transparent zone.

When you save the image, the original color is applied back in the image. Note that during the edition, you can change the transparent color of the image.

Image formats supported by IconWorkshop