Timelapses

On the ‘Data View’ page for a target, a timelapse of FITS data products can be created as animated GIFs or MP4 or WebM video by selecting ‘Timelapse’ in the ‘Pipeline process’ dropdown.

After selecting ‘Timelapse’, two checkboxes are shown to optionally perform extra processing of each frame when the timelapse is created:

• ‘Process each frame to achieve a consistent background brightness across the timelapse’
• ‘Crop each frame in the timelapse around its centre pixel’

The first option prevents the ‘flickering’ that can occur when there are differences in the background brightness across the input files. Note that it can significantly increase the processing time.

The second setting can be used to ‘zoom in’ on the target in the centre of each frame of the timelapse.

Other options can be configured with TOM_EDUCATION_TIMELAPSE_SETTINGS in settings.py, e.g.

TOM_EDUCATION_TIMELAPSE_SETTINGS = {
    'format': 'webm',  # Choose from 'gif', 'mp4' or 'webm'
    'fps': 15,
    'size': 500
    # Scale factor to use when creating timelapses with the 'crop' flag; the
    # dimensions of the original frames are scaled by `scale` in the timelapse
    'crop_scale': 0.5,
}

Here ‘size’ is the maximum width/height to use. The aspect ratio of the input files is maintained.

Management Command

Timelapses can also be created through the management command create_timelapses.

./manage.py create_timelapse <target PK>

This will create a timelapse for all reduced data products associated with the given target that are contained in the data product group ‘Good quality data’. This group name can be changed by setting TOM_EDUCATION_TIMELAPSE_GROUP_NAME in settings.py.