Mosaic

Mosaic plugin

Plugin to create an image mosaic by constructing a composite image.

Plugin Type: Local

Mosaic is a local plugin, which means it is associated with a channel. An instance can be opened for each channel.

Usage

Warning

This can be very memory intensive.

This plugin is used to automatically build a mosaic image in the channel using images provided by the user (e.g., using FBrowser). The position of an image on the mosaic is determined by its WCS without distortion correction. This is meant as a quick-look tool, not a replacement for image drizzling that takes account of image distortion, etc. The mosaic only exists in memory but you can save it out to a FITS file using SaveImage.

When a mosaic falls out of memory, it is no longer accessible in Ginga. To avoid this, you must configure your session such that your Ginga data cache is sufficiently large (see “Customizing Ginga” in the manual).

To create a new mosaic, set the FOV and drag files onto the display window. Images must have a working WCS. The first image’s WCS will be used to orient the other tiles.

Difference from `Collage` plugin

  • Allocates a single large array to hold all the mosaic contents

  • Slower to build, but can be quicker to manipulate large resultant images

  • Can save the mosaic as a new data file

  • Fills in values between tiles with a fill value (can be NaN)