🚀 go-pugleaf

In article <BzBnq5.A05@ie.utoronto.ca> green@ie.utoronto.ca (Marc Green) writes:
>psilsbee@ccwf.cc.utexas.edu (Peter Silsbee) writes:
>
>>Yes, certainly, IF your images are created solely for humans to view, then 
>>that is the best measure. Even so, it must be used with care. Perhaps
                                     ^^^^^^^^^^^^^^^^^^^^^^^^^
>>one reason that it is distrusted is that it, unlike more "objective"
                  ^^^^^^^^^^^^^^^^
>>measures, can be manipulated. I can lossily compress and reconstruct
>>an image, and design a forced-choice experiment that will show that people
>>can't tell the difference. If my application involves magnifying the image
>>by a large factor to locate tiny details, then I've been dishonest. 
>
>This is untrue. If the units are properly specified, i. e., visual angle
>rather than size, etc., you can't manipulate the results.  The trouble is
>not with psychophysics, but with people who don't know how to do it right.
>

Sigh. I knew I shouldn't have added that last bit. Note that I didn't say
that there was anything wrong with psychophysics. I said that the 
human-judgment "measure" (or collection of measures) is DISTRUSTED. 
I have heard people demand MSE figures for evaluation of image compression
algorithms. The fact is, there ARE
people who don't know how to do it right, and there IS potential for 
abuse, since some audiences may know as little (or less) about psychophysics 
as some authors do. I believe that there are conferences, and perhaps
journals, where one could get away scot-free with something along the lines
of what I described above. If you see it, challenge it...

--Peter