1. Image Visualization Requirements German Schumacher Software Engineering Lead JTM, Mar 7, 2017

2. Requirements Basis
Requirements of an Image Visualization System (IVS), to support the verification of the correct functioning of some components under the control of the Telescope & Site.
Image quality could be degraded by the telescope mount behavior and needs to be monitored for its tracking performance, jitter in particular, as well as structural vibrations. On the optics system side, the performance of the active optics system is critical for correcting the aberrations measured by the wavefront sensing process. The environmental control is vital in maintaining a uniform temperature distribution and, compensate for external disturbances like wind. (

3. Requirements Basis
The previous description helps to realize that, a pure visualization of images at different resolutions is not sufficient to uncover quality issues or, find the source of errors. Different computations on the pixel data and, overlay the display of those results along with the image, in the form of text, tables, graphs etc. better serve for that purpose. Likewise, in this context a User Interface (UI) is needed, to select options on the image selection and derived computations to display.

4. From LSE-30
Specification: The LSST Observatory shall provide the means to display images from the FPA (including both science and wavefront sensors) in real time commensurate with the FPA readout, as well as from archived images. This "quick look" display shall support the following global functions:
Pan/zoom quickly and easily to arbitrary resolution
View from laptop/workstation or multi-monitor wall (albeit with performance trade-offs)
Ability to view warning/quality flags via color coding, overlays or some other mechanism
blink / compare images from at least two different exposures

5. From LSE-30
Specification: The "quick look" display tool shall support as a minimum the following analytic functions:
computation of basic statistics (mean, mode, SDEV, etc...) over an arbitrary region of pixel space
line/column plot on any scale
histogram of pixel values in an arbitrary region of pixel space
basic PSF measurements (FWHM, second moments, radial plots profile fitting, etc...)
simple arithmetic between arbitrary regions of two images
overlaying the results of queries to the Engineering & Facility Database

6. Computational capabilities
Specification. The Image Visualization System shall have access to computational capabilities that generates information to be overlay with the image display.
Discussion. This is an important capability in that, we need to consider the possibility that some computations will be performed in computers outside the IVS but, the results must be incorporated into the overlay display the IVS is responsible for.

7. Example Display