Gradient based image SoftCast (G-Cast) reconstructs the image by transmitting gradients and uses structural similarity (SSIM) as the image quality assessment standard. The reconstructed image is more consistent with the perception of human vision system, however, it is a little too smoothed. In order to overcome this disadvantage, a perception-friendly SoftCast scheme using content-based power allocation is put forward in this paper. Firstly, an image block classification algorithm is applied to divide the image into edge blocks, detail blocks and smooth blocks. Secondly, gradients in different blocks are allocated to different power factors according to their importance. As a result, the scheme improves the subjective quality of reconstructed images significantly. At the same time, the objective quality of the scheme is also improved.
Proc. SPIE. 10033, Eighth International Conference on Digital Image Processing (ICDIP 2016)
KEYWORDS: Data compression, Digital image processing, Video, Distortion, Computer programming, Optical flow, Forward error correction, Video coding, Information operations, Current controlled current source
The current interpolation based distributed video codecs get excellent rate distortion performance at the cost of high decoder complexity and delay, which make them almost impractical. An efficient way to solve the problem is to use extrapolation instead of interpolation in side information generation. The proposed codec combines the state-of-the-art optical flow based extrapolation algorithm with modulo operation based low complexity pixel domain distributed video codec and gets high R-D performance. The proposed codec enables the successful encoding and decoding of the frames, thus reducing the delay of the whole system. Simulation results show that the proposed codec outperforms other interpolation and extrapolation based codecs in a series of video sequences. Additionally, the decoding complexity is as low as 1/50 of the traditional distributed video codec without increasing the complexity of the encoder.