Does anyone know of Invariant Theory enough to comment on this question?

I am trying to find a minimal set of invariants for the binary homogenous form $$\displaystyle ax^7 + bx^{6}y + cx^{5}y^{2} + dx^{4}y^{3} + ex^{3}y^{4} + fx^{2}y^{5} + gxy^{6} + hy^{7}$$ What is the basis for all of the invariants for this form? Is there an easier way like using properties of symmetry without going through the crazy calculation? I've already calculated the binary form when the leading term's degree is 2,3 and 4 using the software SAGE.

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If people are unsure about what they are going to talk about, they usually don't talk. Given this fact, this title is superfluous. Please consider editing the title to put in something more informative. Regards, –  user21436 Apr 15 '12 at 10:54
Sorry Kannappan, I will make my questions clearer next time –  Low Scores Apr 20 '12 at 0:26