For a JPG image, I can just use CGImageSourceCopyPropertiesAtIndex to obtain the various bits of EXIF information from the image. However, this API does not work with quicktime movie files.
What similar Cocoa APIs can I use to extact EXIF information from a Quicktime movie file?
EXIF is a standard for image files, not for movies. There's no EXIF information defined for movies and correspondingly there's no API to retrieve them from quicktime movie files.