Generating Static Previews

Roman archiving requires static preview images for viewing and selecting images, with the following requirements for each ImageModel:

  • 1080p x 1080p preview image

  • 300p x 300p thumbnail image

  • output as PNG files

  • 90th percentile linear histogram stretch

  • using afmhot colormap

  • overlay indicating orientation

The roman_static_preview script creates downsampled images from ASDF files containing an ImageModel, with an optional compass rose overlayed onto the image indicating orientation.

Installation

The requirements for this script are not installed by default as part of romancal; install with the sdp extra to include them.

pip install "romancal[sdp]"

Usage

roman_static_preview includes two convenience commands, preview and thumbnail, that set default options to the static preview requirements.

❯ roman_static_preview preview --help
Usage: roman_static_preview preview [OPTIONS] INPUT [OUTPUT] [SHAPE]...

  create a preview image with a north arrow overlay indicating orientation

Arguments:
  INPUT       path to ASDF file with 2D image data  [required]
  [OUTPUT]    path to output image file
  [SHAPE]...  desired pixel resolution of output image  [default: 1080, 1080]

Options:
  --compass / --no-compass  whether to draw a north arrow on the image
                            [default: compass]
  --help                    Show this message and exit.

❯ roman_static_preview thumbnail --help
Usage: roman_static_preview thumbnail [OPTIONS] INPUT [OUTPUT] [SHAPE]...

Arguments:
  INPUT       path to ASDF file with 2D image data  [required]
  [OUTPUT]    path to output image file
  [SHAPE]...  desired pixel resolution of output image  [default: 300, 300]

Options:
  --compass / --no-compass  whether to draw a north arrow on the image
                            [default: no-compass]
  --help                    Show this message and exit.

Examples

roman_static_preview preview r0000501001001001001_01101_0001_WFI01_cal.asdf r0000501001001001001_01101_0001_WFI01_cal.png 400 400
preview of Roman imagery, with compass rose showing orientation 
roman_static_preview thumbnail r0000501001001001001_01101_0001_WFI01_cal.asdf r0000501001001001001_01101_0001_WFI01_cal_thumb.png
thumbnail of Roman imagery

using stpreview directly

The roman_static_preview script is merely a wrapper over stpreview to, which offers more options for fine-grained control of the output image. stpreview offers the to and by commands (for resampling to a desired image shape, or by a desired factor, respectively). Refer to the documentation for usage instructions.