Fast Quadtree Based Normalized Cross Correlation Method for Fractal Video Compression using FFT

Abstract

-In order to achieve fast computational speed with good visual quality of output video, we propose a frequency domain based new fractal video compression scheme. Normalized cross correlation is used to find the structural self similar domain block for the input range block. To increase the searching speed, cross correlation is implemented in the frequency domain using FFT with one computational operation for all the domain blocks instead of individual block wise calculations. The encoding time is further minimized by applying rotation and reflection DFT properties to the IFFT of zero padded range blocks. The energy of overlap small size domain blocks is pre-computed for the entire reference frame and retaining the energies of the overlapped search window portion of previous adjacent block. Quadtree decompositions are obtained by using domain block motion compensated prediction error as a threshold to control the further partitions of the block. It provides a better level of adaption to the scene contents than fixed block size approach. The result shows that, on average, the proposed method can raise the encoding speed by 48.8 % and 90 % higher than NHEXS and CPM/NCIM algorithms respectively. The compression ratio and PSNR of the proposed method is increased by 15.41 and 0.89 dB higher than that of NHEXS on average. For low bit rate videos, the proposed algorithm achieve the high compression ratio above 120 with more than 31 dB PSNR.

Review on Fractal Video and Image Compression Techniques

“…In general, the main challenges of fractal compression systems are compression ratio (CR), peak signal to noise ratio (PSNR) and Encoding time. From the Table I that contains the summary of some previous work, where high compression ratio (CR) with reasonable Encoding time of image compression was achieved in [21] when they used Featuring Deep Data Pipelining Strategy on Lena image (1024×1024) with block size (8×8) , but the quality of image was very poor as compared with others, while high compression ratio(CR) of video compression was achieved by using "Fast Quadtree using normalized cross correlation Method using FFT " in [18] for 'Foreman' video with frame size(352×288) and block size(4×4 ) but this technique required high Encoding time .…”

A Data Encryption and Fast Transmission Algorithm Based on Surveillance Video

“…Rahaman and Paul [17] use different coding methods to compress data according to its importance. Chaudhari and Dhok [18] transform video into frequency domain analysis and coding. Abbas et al [19] use optical code division multiple-access networks.…”

Video Compression based on Fractal Isosceles Triangular Partition using Hybrid Swarm Intelligence

“…The mapping of symmetry reduces the space of non-overlapping blocks of domain and range. The process of fractal encoding describes here with the figure 1 [16][17][18][19][20][21][22][23].…”