Yes, they had the plain text shader files embedded in their app, easily extractable. It's been like that since they first released 2.0. Path has (or had) them embedded, too. It's still their IP though, and publishing them as "open source" is unethical and probably illegal. Just because something is feasible doesn't mean you should do it. The GPUImage-based execution environment is fine, but you should remove these sh…
PNG files are obfuscated, but that's reversible:
http://www.axelbrz.com.ar/?mod=iphone-png-images-normalizer
This kind of spelunking can be a good way to learn from other developers about how to approach some problems. However, I agree with other commenters that it would be morally shaky to re-use any of another app's files in my own app.