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Experience Now...
Pixelfusion
What is it then?
Pixelfusion is basically an image resampling method.
There are many resampling methods already available, ranging
from point sampling, to bilinear, bicubic or even
windowed sinc. Pixelfusion is different to all of these in one very
important aspect, as we will find out later.
So what exactly is resampling, and why do we need it?
A single frame in a video, or image, is made of a grid of different coloured
dots, or 'pixels'. The size of the grid is described as the number of columns
x the number of rows of pixels, or width x height, and this is usually referred
to as the resolution. An example of the resolution of an image might be
512 x 384, where it would have 512 pixels going across, and 384 pixels going down.
The display on a computer also has a resolution, which defines the number
of pixels that are actually displayed on the screen. This is typically
1024 x 768. An image is displayed by setting the display pixels to
the same colour as the pixels in the image. In our example, the image does not
have a sufficient number pixels to fill the entire display, it will in fact fill
exactly a quarter of the display.
This would be fine if the image was displayed in a window, but if the image
was required to fill the entire screen there must be a method for increasing the
resolution of the image so that it matches the resolution of the display. The
simplest method to do this is to simply duplicate the pixels, this is
point sampling. In our example, each pixel would be duplicated to become
a group of 4 pixels next to each other, arranged as a square of 2 x 2. Put
these groups of pixels together, and you eventually end up exactly filling
the screen.
Point sampling is great, the only problem is that it doesn't look natural.
The results look pixellated, this is great as an effect in a paint package but
not when watching a video or viewing an image. The technical term for the
error produced is aliasing. At the boundary of each group of pixels there are
sharp edges, which do not exist in
the original image. The accepted method for removing the fake edges is to
perform a filter, to literally filter out the bad edges. Bilinear and bicubic
filtering are the industry standard algorithms, bicubic generally giving the
smoothest and more natural results.
After bilinear/bicubic filtering, the image now looks natural and faithful to
the original, but it appears blurry. The filtering has removed the high frequency
components of the image, or in other words, the 'crispness' of the image.
The image can be sharpened to some degree, but this can result in undesired
halo effects around edges, more to the point it still does nothing about the lost
frequency components.
Pixelfusion brings back definition to video and images.
During the Pixelfusion process, parts of the image where there should be
high frequency
components have a special algorithm applied to them to actually add details
back into the image. The result is a much clearer image, while still
remaining natural to the eye.
We have developed 5 enhancement modes, each of varying complexity and
quality :- 4 modes are designed for realtime video (low, medium, high
and ultra), and one mode is
designed for images. The current mode can either be selected manually, or
automatically. The automatic mode uses factors such as the current CPU load,
image resolution and video framerate to determine the
highest quality Pixelfusion mode which can be used without causing the video
to skip.
Each mode is fully optimised in assembler, using Intel MMX
or SSE2 instructions
if the CPU supports them, for the fastest execution possible.
Experience neuview now for $12.99
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