PICTURE QUALITY MEASURING METHOD

摘要

PURPOSE:To make quality correspondent with objective quality with high accuracy by calculating a frequency spectrum of a distortion component resulting from orthogonal conversion to a difference signal between an original picture and a picture to be measured for each prescribed measurement unit time and using a signal applying inverse orthogonal transform to the weighted frequency spectrum so as to attain quantitative evaluation of picture quality in time series. CONSTITUTION:A difference signal extraction section 2 receiving an original picture signal 1-1 and a picture signal 1-2 to be measured calculates a difference between both the signals 1-1, 1-2 and the difference signal is sent to a transform section 4 to a succeeding frequency axis synchronously with a frame timing signal 3. Then the frequency spectrum obtained in the section is regarded as one time base waveform and a Fourier transform section 5-1 of a visual sensitivity correction section 5 applies Fourier transform to the signal again. An output from the Fourier transform section 5-1 is subject to visual sensitivity correction by using a weighting calculation section 5-2. An evaluation difference power calculation section 7 calculates a mean value as to the difference signal weighted by a time axis inverse conversion section 6, calculates the power in the unit of frames and displays the result of measurement on a display section 8 as the evaluation S/D.