Frequency domain: Efficient and high speed technology for video transmission
Motion Estimation (ME) consumes up to 70% of the entire video encoder's computations and is, therefore, the main encoding-time consuming process. Using DCT along with Adaptive Padding (AP) in frequency domain are the recently evolved Frequency Domain ME (FDME) techniques that efficiently reduce the ME computational complexity. There are two main problems of using such conventional AP in the frequency domain. Firstly, the adaptive thresholds need to be estimated in the pixel (IDCT) domain which increases complexity. Secondly, the mismatched transformed search area is formed from different successive transformed blocks, which would lead to an inaccurate ME if the search area is not manipulated. In this paper, an efficient low complexity algorithm and high speed architecture are proposed to implement an adaptive Manipulation Unit (MU). The MU, the main module of the FDME system, adaptively decides the padding size and forges a matched transformed search area from the successive transformed blocks. Additionally, the proposed utilized adaptive thresholds are efficiently estimated in the Frequency Domain (FD). The MU architecture is presented with two different design implementations trading off the VLSI design parameters.