Methods and apparatus to detect differences between images are disclosed. Example methods disclosed herein to recognize different image versions include generating a first signature representative of a sample image, and obtaining a reference image associated with a second signature determined to substantially match the first image signature. Such example methods also include generating a third signature representative of a first region of the sample image corresponding spatially to a first region of the reference image associated with a first version of the reference image, the third signature being different from the first signature. Such example methods further include comparing the generated third signature and a fourth signature representative of the first region of the reference image to determine whether the sample image corresponds to the first version of the reference image.