Motion estimation is an important component in video compression schemes which impacts the encoder performance and the quality of the reconstructed video sequence. Block-based techniques are the most popular among the several motion estimation techniques used in practice due to their simplicity allowing efficient hardware implementations. The quality of motion predicted frame and the speed of motion vector computation are the primary measures of performance of motion estimation schemes. The video compression standards only specify the syntax of the bitstream and not any specifics of the motion estimation techniques. Thus, the knowledge of the workings and performance of commonly used motion estimation schemes would facilitate development of better schemes or choosing a particular one for a given application. This paper presents the results of performance evaluation of combinations of several commonly used block-based motion estimation algorithms and distortion measures.