When you add an image to the Image tab in the Properties dialog box of an object, you can choose to ignore a colour or a range of similar colours in an image so as to make the background of an image transparent, like in this illustration:
Note:
In the case of PNG and GIF files (which contain transparency information) Opus will automatically read this information and ignore the portion of the graphics marked as transparent.
Click on the Transparent option in the Image tab of the object’s Properties dialog box.
Click on the drop down button beside the Colour box to select your colour. This will open a drop down colour well.
Note:
There are a variety of methods for choosing your colour in the drop down colour well. These include selecting a colour from the colour palette, opening the Colour Selector dialog box with the Custom button, or using the Colour Picker button to match a colour on your screen.
With the subtlety of colour which modern systems can now display it can be difficult to judge the required colour by eye therefore, the colour-picker tool is the best way to choose the transparent colour as you can pick it from the copy of the image displayed in the preview box.
Drag the colour slider under the Colour box if the colour you want to ignore is not a solid colour. This will increase the range of that particular colour that will be ignored.
Click on the Apply button to save your changes.