Great tool! I always meant to write it myself...
A couple of notes:
Some mixer parameters don't have an associated value range, (e.g. they're enums which could theoretically be disjoint)
CHROMA_TYPE y 00000001 00001000
Same thing for some mixer attributes.
The type of mixer attributes can vary (as indeed can mixer parameters). For example, these are floats, not ints:
NOISE_REDUCTION_LEVEL y 00000000 3f800000
SHARPNESS_LEVEL y bf800000 3f800000
The docs in the header should indicate all the details for the various parameters/attributes.