The RGB extension is associated with colour or black-and-white bitmap images released under the SGI (Silicon Graphics Image) format. Similar extensions include RGBA and BW. All were initially designed in the mid-1990s for use on Silicon Graphics workstations and are currently considered rare and obsolete.
The quick and simple way to handle your files is to get a quality piece of software, such as reaConverter. This software is extremely efficient in managing a wide range of batch conversions. As you will soon realize, reaConverter will help you avoid spending countless hours trying to figure out how to convert multiple RGB files as once.
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