基于matlab的mpeg4视频压缩（毕业设计）

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%% %%% FUNCTION: metrix_psnr %%% %%% INPUTS: reference_image - original image data %%% %%% query_image - modified image data to be compared with %%% original image %%% %%% OUTPUTS: metrix_value - PSNR value %%% %%% CHANGES: NONE %%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%% Author: Matthew Gaubatz %%% Version: 1.0 %%% Date: 01/05/2007 %%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%% Copyright (c) 2007 Visual Communications Lab, Cornell University %%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%% Permission to use, copy, modify, distribute and sell this software %%% and its documentation for any purpose is hereby granted without fee, %%% provided that the above copyright notice appear in all copies and %%% that both that copyright notice and this permission notice appear %%% in supporting documentation. VCL makes no representations about %%% the suitability of this software for any purpose. %%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%% DISCLAIMER: %%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%% The code provided hereunder is provided as is without warranty %%% of any kind, either express or implied, including but not limited %%% to the implied warranties of merchantability and fitness for a %%% particular purpose. The author(s) shall in no event be liable for %%% any damages whatsoever including direct, indirect, incidental, %%% consequential, loss of business profits or special damages. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% function [metrix_value] = psnr(reference_image, query_image) reference_image =double(reference_image); %注意数据类型一致和转换！读入图像的矩阵是uint8类型，在数据处理时为了精确，采用double类型。 query_image =double(query_image); mse_value = mean( (reference_image(:) - query_image(:)).^2 ); metrix_value = 10*log10( 255*255 / (mse_value+1) );