Low-Complexity Chroma Subsampling Using Optimal Lines of Subproblems of Pixel Distortion

Video compression is an important procedure for digital applications. A commonly used format inputs to video coders YUV420, which a subsampled result from YUV444, that transformed and demosaicked color filter array (CFA) format. The process of chroma subsampling crucial step the reconstructed image quality. state-of-the-art method utilizes solution prior compute starting point, devises search improve results. However, does not consider optimality condition problem, overall computational complexity high because execution point. In proposed work, cost function optimization problem analyzed decomposed into 4 subchannels based on CFA optimal line each subterm studied in 3-dimensional space. then mathematically reduced 3-subchannel problem. Based combinations lines, triangle area formed proved contain solution. And derived small average, value can be considerably fast. Experimental results demonstrate approach produce images with qualities are exactly same as those generated using method. Relative method, reduce time by 84.08%–84.91%, number points 40.24%–85.25%, datasets Kodak IMAX different demosaicking methods.