7. A system, comprising: one or more computers including one or more storage devices storing instructions that when executed by the one or more computers cause the one or more computers to perform operations comprising: generating a first image based on a first search query; generating a second image based on a second search query; generating a first set of wavelets corresponding to the first image; generating a second set of wavelets corresponding to the second image; generating a first signature for at least some of the wavelets corresponding to the first image; generating a second signature for at least some of the wavelets corresponding to the second image; and determining whether the first search query and the second search query are related queries based on comparing at least part of the first signature and at least part of the second signature.
10. The system of claim 7 , wherein the operations comprise: identifying the at least part of the first signature and the at least part of the second signature using at least one hashing scheme.