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Lots of recent discussion on PQ, with some describing their results with test patterns, circles, etc.
I used such patterns previously with my analog video systems and knew they were usually reserved for "aligning" systems from an input to an output that was viewable -- a CRT or TV, for example.
Since we've got one foot in the digital world with our DVDRs, and many broadcasts are digital, things have changed a bit. We try to describe PQ with "what we see" on our TVs, and it turns out that's pretty much the way to do it, at least for us "home-users."
I found some interesting reading on the subject in this entry in Wikipedia . A pertinent point in that entry:
"From analog to digital video
In the ages of analog video systems it was possible to evaluate the quality of video processing system by calculating the frequency response of some traditional test signal (for example, a collection of color bars and circles).
Nowadays digital video systems are replacing analog ones, and evaluation methods must be changed. Performance of digital video processing system can vary powerfully and depends on dynamic characteristics of input video signal (e.g. motion, level of spatial details). That's why digital video quality must be evaluated on video sequences that can be actually received by users."
The Wiki entry ( ]linked again here ) has several other linked refs. for people interested in this subject.
I used such patterns previously with my analog video systems and knew they were usually reserved for "aligning" systems from an input to an output that was viewable -- a CRT or TV, for example.
Since we've got one foot in the digital world with our DVDRs, and many broadcasts are digital, things have changed a bit. We try to describe PQ with "what we see" on our TVs, and it turns out that's pretty much the way to do it, at least for us "home-users."
I found some interesting reading on the subject in this entry in Wikipedia . A pertinent point in that entry:
"From analog to digital video
In the ages of analog video systems it was possible to evaluate the quality of video processing system by calculating the frequency response of some traditional test signal (for example, a collection of color bars and circles).
Nowadays digital video systems are replacing analog ones, and evaluation methods must be changed. Performance of digital video processing system can vary powerfully and depends on dynamic characteristics of input video signal (e.g. motion, level of spatial details). That's why digital video quality must be evaluated on video sequences that can be actually received by users."
The Wiki entry ( ]linked again here ) has several other linked refs. for people interested in this subject.
