This image corresponds to Figures 7-6 through 7-11 in the book. Using GIMP’s Channels, you can isolate an object from its background and swap it with a new one. The XCF file below shows the layers and channels that went into creating this image (note: there’s no need to decompress this file. GIMP can read .xcfbz2 files natively). Please note that the XCF file does not include the background image used in the book. For that, you have to go to cgtextures.com. Photo credit: Chris Hoyer, www.chrishoyer.com, used with permission.
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