Hi,

In message , "Dave Plowman (News)"
writes
In article ,
tony sayer wrote:
As for the picture, it's different, but is it better????

Not in my opinion, against good analogue PAL...

I tend to notice the lack of detail in flesh tones.

We did some acceptability tests at work recently for MPEG video codecs.
During the 'training' phase, most subjects were understandably very
vocal about the 'shimmering' green tones in the grass on a football
field, and almost all rated it as being objectionable.

Nobody (out of 20 subjects) noticed that in the same piece of video, a
player's leg had become separated at the knee, and flown off as he
kicked the ball. The leg subsequently disappeared a third of the way
across the pitch, due to a very dodgy motion prediction algorithm.
People were amazed when it was pointed out to them; they just didn't see
it.

Unfortunately, it doesn't seem to take much critical viewing time to
learn to spot digital video compression artefacts, and once you start to
see them, there's no going back (at least in my case). I'm continually
critical of Sky Digital video quality, especially on the lower bitrate
channels.

As you point out, flesh tones are a prime culprit. Any areas of subtly
varying tones, especially with green content, seems to suffer this
problem.

--
Regards,
Glenn Booth