ADS Technologies USBAV-708 INSTANT VIDEOMPX, User Manual

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Because both psychovisual enhancement methods mask artifacts in textured
areas where they are least visible the video quality appears to improve when
psychovisual enhancements are enabled. You can visualize the concept by
imagining two characters having a conversation while standing in front of a tree—
the psychovisual enhancement process might enhance details in the characters
faces at the expense of causing some artifacting amongst the leaves of the tree
where it would be least perceivable.
The best way to understand the psychovisual enhancements is to watch them
working on an image. The feedback window provides an excellent method of
doing this, and also allows you to configure the degree to which flat and texture
psychovisual enhancements are performed.
Set up a 1-Pass encoding using VirtualDub
and any source video of your choosing with
Fast psychovisual enhancement mode
enabled. Begin encoding and click the Pause
button on the encoder feedback window
when a suitable image to work with appears.
Set
Show picture to encoded frame and
enable the pvLumaFlat and pvLumaTexture
controls in the bottom panel.
With the video paused slowly drag each slider back and forth from zero (no
psychovisual enhancement) to one (full psychovisual enhancement), watching
the image carefully as you do so. Since the aim of psychovisual enhancement is
to mask artifacts where you are least likely to perceive them you should see that
both effects appear to improve quality when enabled to fuller extents.
By enabling the Data overlaying controls and
configuring them to show the PV level and color
the Full macroblock based also on the PV level it
is possible to view graphically the changes made
in a more statistically-orientated way.
Where information is removed from the image the number overlaid will be
positive and the macroblock tinted red. Where information is added to the image
the number overlaid will be negative and the macroblock tinted blue.
Experiencing PVE