As one of the crucial problems in watermarking, robustness against geometric distortion and JPEG compression becomes more than challenging and problematic. In this paper, a robust and geometric invariant watermarking scheme using block histogram and intensity-level histograms is proposed. During watermark embedding procedure, we first compute the number of valid intensity-levels of the given image, and group the pixels into blocks of variable size such that each of which has the same number of intensity-levels. Thus the block histogram is generated for the given image. Then the intensity-level histogram of each block is modified according to the embedding bits of the watermark. During the extraction procedure, the block histogram and intensity-level histogram of each block in the watermarked image are generated in a similar manner and the watermark is decoded according to the distribution of the intensity-level histogram in each block. Experimental results show that the proposed schem...