1、TECHNICALREPORTIEC TR 62251First edition2003-05Multimedia systems and equipment Quality assessment Audio-video communication systemsReference numberIEC/TR 62251:2003(E)LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.Publication numberi
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8、03 00LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.TECHNICALREPORTIECTR 62251First edition2003-05Multimedia systems and equipment Quality assessment Audio-video communication systemsPRICE CODE IEC 2003 Copyright-all rights reservedNo
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11、BUREAU.2 TR 62251 IEC:2003(E)CONTENTSFOREWORD.41Scope.52References.53Terms and definitions.64Configuration for quality assessment.64.1Input and output channels.64.2Points of input and output terminals.75Video quality.85.1Introduction.85.2End-to-end tone reproduction.95.3End-to-end colour reproductio
12、n.115.4End-to-end colour differences.125.5End-to-end peak-signal to noise ratio(PSNR).165.6End-to-end objective assessment of video quality.206Audio quality.216.1Perceived audio quality with full-reference signals.216.2Sampling rate and quantization resolution.236.3Delay.247Total quality.247.1Synchr
13、onization of audio and video(lip sync).247.2Scalability.257.3Overall quality.26Annex A(informative)PSNRs defined in three-dimensional spaces applied tohypothetical deterioration over the reference video sources.27Annex B(informative)End-to-end objective assessment of video quality in spatialfrequenc
14、y domain.31Annex C(informative)PEAQ objective measurement method outline.36Bibliography.40Figure 1 Model of audio-video communication systems.7Figure 2 Schematic diagram for quality assessment.7Figure 3 The image of the grey steps defined in IEC 61146-1.9Figure 4 An example plot of tone reproduction
15、.10Figure 5 The image of the colour reproduction chart defined in IEC 61146-1.11Figure 6 Colour differences between reference and streamed video frames at 250 kbpsand 30 fps.15Figure 7 Examples of PSNR assessment.19Figure 8 Basic concept for making objective measurements.22Figure 9 Representation of
16、 PEAQ model.22Figure B.1 Assignment of the block numbers.31Figure B.2 Example of wavelet decomposition visualised.31LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.TR 62251 IEC:2003(E)3 Figure B.3 Trends of difference of coefficients of wavelet transform betweenreference and streamed video frames at 250 kbps and 30 fps.34Figure C.1 Basic concept for making objective measurements.36Figure C.2 Representation of PEAQ model.37Figure C.
