Required Plugins for the GIMP

There are several plugins for the GIMP that really should be kept at hand. I've listed these with their URL in the GIMP Plugin Registry.

GIMP Wavelet Denoise

http://registry.gimp.org/node/4235

The wavelet denoise plugin is a tool to reduce noise in each channel of an image separately. The default colour space to do denoising is YCbCr which has the advantage that chroma noise can be reduced without affecting image details. Denoising in CIELAB (L*a*b*) or RGB is available as an option. The user interface allows colour mode and preview channel selection. The denoising threshold can be set for each colour channel independently.

GIMP Wavelet Sharpen

http://registry.gimp.org/node/9836

The wavelet sharpen plugin enhances apparent sharpness of an image by increasing contrast in high frequency space. The amount of unsharpness of the original image can be taken into account by adjusting the sharpening radius. As an option one can choose to sharpen the luminance (YCbCr) channel of the image only.

GIMP Simple Bilateral Blur

http://registry.gimp.org/node/24208

This is a surface blur filter based on a simplified version Porikli's O(1) bilateral filter.

GIMP Astronomy Plugins

http://registry.gimp.org/node/2352

A set of plugins and scripts for astronomical image processing. These are not intended for scientific image processing.

Plugins:

• Align layers using centre of brightness or 2D (fourier) cross correlation or gauss fit, subpixel-resolution, with de-rotation! • Merge layers using different mean values, including arithmetic/geometric mean, median, and arithmetic mean of x sigma around median.

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Create a background gradient (artificial flat field) from a layer by fitting a 2D 4th order polynomial through pivotal points. Cut out large bright nebulae to avoid wrong pivotal point values! Star rounding: Round longish stars (due to tracking errors...) Create an artificial galaxy. Only elliptical galaxies yet. Create artificial stars: Using different star distributions, split into background, object and foreground stars.

Scripts:

Set mode for all layers Set brightness / contrast for all layers Normalize all layers Subtract dark frame from each layer Divide all layers by a flat field Draw border with image information

GIMP Exposure Blend

http://registry.gimp.org/node/6708

This is the 'HDR' plugin. Exposure-blend makes quick work of blending 3 bracketed exposures into a detailed, realistic, extended contrast image. It has many features to save the drudgery of assembling contrast blended stacks yourself.

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Do It Yourself Section Simple things that anyone handy can put together

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