astropy.visualization provides functionality that can be helpful when visualizing data. At the moment, the main functionality is image normalizing (including both scaling and stretching). Another feature included here is a plotting style for matplotlib.
This module includes a command-line script, fits2bitmap to convert FITS images to bitmaps, including scaling and stretching of the image. To find out more about the available options and how to use it, type:
$ fits2bitmap --help
| scale_image(image[, scale, power, asinh_a, ...]) | Perform scaling/stretching of an image between minimum and maximum cut levels. |
| AsinhStretch | An asinh stretch. |
| AsymmetricPercentileInterval(...[, n_samples]) | Interval based on a keeping a specified fraction of pixels (can be asymmetric). |
| BaseInterval | Base class for the interval classes, which, when called with an array of values, return an interval computed following different algorithms. |
| BaseStretch | Base class for the stretch classes, which, when called with an array of values in the range [0:1], return an transformed array of values, also in the range [0:1]. |
| BaseTransform | A transformation object. |
| CompositeTransform(transform_1, transform_2) | A combination of two transforms. |
| ContrastBiasStretch | A stretch that takes into account contrast and bias. |
| HistEqStretch | A histogram equalization stretch. |
| LinearStretch | A linear stretch. |
| LogStretch | A log stretch. |
| ManualInterval(vmin, vmax) | Interval based on user-specified values. |
| MinMaxInterval | Interval based on the minimum and maximum values in the data. |
| PercentileInterval(percentile[, n_samples]) | Interval based on a keeping a specified fraction of pixels. |
| PowerDistStretch | An alternative power stretch. |
| PowerStretch | A power stretch. |
| SinhStretch | A sinh stretch. |
| SqrtStretch | A square root stretch. |
| SquaredStretch | A convenience class for a power stretch of 2. |
Normalization class for Matplotlib that can be used to produce colorbars.
| ImageNormalize([vmin, vmax, stretch, clip]) | Normalization class to be used with Matplotlib. |