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Resampling
Deblurring
Dejpeg
Denoise
Deconvolution
Dequantization
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DJ-M-Spline - the new, linear and best quality algorithm of image cleaning.
JPEG compression breaks an image into
rectangular blocks, each representing 8 x 8 pixels of detail, and then
independently compresses each block. The result of JPEG compression on a file
that was of poor original quality is an ugly, repetitive pattern of blocks.
Sometimes the distortions are striking enough to be visible, and those are
called artifacts.
There are
some versions of artifacts:
Blocking artifacts:
Baseline JPEG
can only work with 8x8 blocks, one at a time. This causes the best known
artifact in compressed images - small square blocks all over the images,
known both in JPEG and in video decoders.
Color distortion:
As human eyes
are not as sensitive to color as to brightness, much of the detailed color (chrominance)
information is disposed, while luminance is retained. This process is called
"chroma subsampling", and it means that a color image is split into
a brightness image and two color images.
Ringing artifacts:
Both JPEG2000
and JPEG operate in spectral domain, trying to represent the image as a sum
of smooth oscillating waves.
Blurring artifacts:
Blurring
means that the image is smoother than originally. The pictures were stored at
approximately 2.0 bits per pixel, four times weaker compression rate as
above.
JPEG Repair - The filter
provides improved image quality, removes the so-called 'JPEG artifacts' and
improves image clarity. Until
recently, there were only three linear methods allowing the clear of image –
blur, smart blur and noise reduction. The main advantage of these methods is
high speed of the realization. However, their application leads to a strong
artifacts which, by permanently increasing demands for quality of cleaning,
significantly limits the area of their application.
Recently,
on the market of professional graphic programmes, quite a few more effective
and better quality algorithms have appeared. Along with the linear methods
non linear (adaptive) algorithms appeared – Net Image 5.1, Define, Cleanerzoomer, Jpeg
Enhancer, Un Jpeg etc. Notwithstanding the
diversity of existing methods of noise and removes of jpeg artifacts, Jpeg
Enhancer and Cleanerzoomer
are
generally recognized as ones of the best quality and the most accurate.
However, because none of the said methods does not get an identically good
result, the work to create new algorithms is still ongoing with various success.
The aim of
data spelling appears as the presentation
of the new linear method which allows to carry out removes of jpeg
artifacts a better quality, better than all known methods, both linear and
adaptive. The main advantage of suggested method over the rest of them is the
speed (because it appears linear) simpleness of its realization and best
quality closest to achievable limits. The method brought to your attention
was called Magic spline or M-spline by its author.
Dejpeg-M-spline - algorithm
is fully worked out and realized exclusively by the author and all the rights
of its use until the decision of sale, belong to the author.
The base of
the suggested algorithm (M-spline) lies in application of the new PSN&ER
metrics (peak to peak signal to noise and edges ratio) which significantly
more accurate (compared with PMS metrics) agrees with the visual valuation of
similarity and the new revolutionary approach at working out the algorithm.
Valuating the form and size of approximating function, it is also possible to
ascertain that obtained algorithms allow getting the quality of the removes
of jpeg artifacts which is maximally approximate to the achievable limit from
the theory of information point of view. There are also a few algorithm
modifications.
In order to
confirm above, I suggest to get familiar with practical realization of the
algorithm on the well known examples of tasks and solutions.
As the
test the following representation has been chosen:
flowers
lhouse2
 
To see the picture click on the fragment
Test - flowers
The resolution of image will be enlarged by 4 times
Original
Cleanerzoomer Jpeg Enhancer DJ-M-Spline
(New
method) enlarged by 2 times
   
   
   
   
Test – flowers
Chrominance
component
The resolution of image will be enlarged by 4 times
Original Jpeg
Enhancer DJ-M-Spline
(New method) enlarged by 2 times
  
Test - lhouse
The resolution of image will be enlarged by 4 times
Original Cleanerzoomer Jpeg Enhancer DJ-M-Spline
(New method) enlarged by 2
times
   
   
The real images will be enlarged by 2 times
Original DJ-M-Spline
(New method) enlarged by 2
times
 
 
 
Your
comments and questions:
vitalybn@fpy.ru
resampling@yandex.ru
vitalybn@yahoo.com
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