BIG - High-Quality Resize
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High-Quality Resize Example
This simple example shows the kind of improvement that can be obtained if we use the projection method instead of the standard (interpolation and resampling) approach.

The original image was first reduced and then magnified back to its original size. In both cases, the underlying continuous image model is a separable linear spline. The standard approach performs resizing by simple resampling, while the projection methods implements the least-squares approximation.


Standard interpolation approach

Original Magnetic-Resonance image

Reduction by 0.5619

Error image, which clearly shows that we have lost most of the fine details of A (edges).

Reduced/Expanded image;you can observe the blurring;the SNR is 31.9216 dB.

New projection method

Original Magnetic-Resonance image

Reduction by 0.5619

Error image. Comparing the original with the Red/Exp image demonstrates that most of the high-frequency information is kept.

Reduced/Expanded image; the SNR is improved to 35.0063 dB.
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