An Efficient Soft Decoding for Wavelet Video Compression with Global Motion Compensation

This paper is dedicated to low-complexity video coding based on three-dimensional discrete wavelet transform (3-D DWT). We propose four modifications of our previously proposed 3-D DWT codec including replacement of 5/3 LeGall 2-D wavelet transform by CDF 9/7 2-D wavelet transform, fast global motion compensation which is combined with 1-D temporal transform implemented via simple cycling shift approach, skipping of entropy encoding of subband blocks based on parent-child dependency, and soft decoding via iterative shrinkage-thresholding algorithm taking into account the global motion compensation. Experimental results obtained at Full HD test video sequences with medium and high motion level show that the modified 3-D DWT codec outperforms the fastest implementation of H.264/AVC (x264 in ultrafast and superfast presets) in both encoding speed and in rate-distortion performance making it more preferable for real-time video compression for transmitting devices with limited computational resources.