We develop an algorithm for solving a system of diophantine equations with
lower and upper bounds on the variables. The algorithm is based on lattice
basis reduction. It first rinds a short vector satisfying the system of dio
phantine equations, and a set of Vectors belonging to the null-space of the
constraint matrix. Due to basis reduction, all these vectors are relativel
y short. The next step is to branch on linear combinations of the null-spac
e vectors, which either yields a vector that satisfies the bound constraint
s or provides a proof that no such Vector exists. The research was motivate
d by the need for solving constrained diophantine equations as subproblems
when designing integrated circuits for video signal processing. Our algorit
hm is tested with good results on real-life data, and on instances from the
literature.