No package 'gstreamer-app-1.0' found

Folks, I’m trying to install a tool called spacelapser, one of the steps is to run $ ./compileOF.sh inside the OF linux scripts folder. I’ve tried a lot of things but I’m a real beginner with all this Ubuntu stuff, it always gives me the error:

Package gstreamer-app-1.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `gstreamer-app-1.0.pc'
to the PKG_CONFIG_PATH environment variable
No package 'gstreamer-app-1.0' found
Package gstreamer-app-1.0 was not found in the pkg-config search path.
Perhaps you should add the directory containing `gstreamer-app-1.0.pc'
to the PKG_CONFIG_PATH environment variable
No package 'gstreamer-app-1.0' found
makefileCommon/config.shared.mk:305: *** couldn't find gstreamer-app-1.0 pkg-config package or it's dependencies, did you run the latest install_dependencies.sh?.  Stop.
there has been a problem compiling Debug OF library
please report this problem in the forums

I have no clue to what this means, could you guys help me?