#### 3.5 The animation window

This window allows you to display a series of spectra from the global list, one after the other. It is possible to display these into an existing plot, that may already be displaying other spectra you’d like to use for comparison, or you can use a new plot.

With careful control of the plotting options you can display into a plot with fixed data ranges, or see each spectrum plotted as autoscaled.

It is also possible to use this window to generate a series of JPEG or PNG images that you could combine into a movie of some kind.

Global list of spectra:

As in the browser window this is a view of the spectra currently stored in the global list. Initially all the spectra in the list are selected, but you may modify which spectra to animate by creating your own selection (reminder: the combination of shift-left-mouse click selects the range between the last selected row and the current position, and the combination control-left-mouse click, either adds the current row to the selection, or removes it, if already selected).

Animation controls:

The Delay: field accepts a decimal number of seconds to pause between displaying the selected spectra. You can modify this during an animated sequence by pressing the <Return> key.

The Loop forever: checkbox determines whether the animation sequence is restarted when all the selected spectra have been displayed. If set then you need to press the Stop button to stop the animation.

The Plot: drop-down list contains a list of all the currently available plots and the special entry Create. If the Create option is chosen then a new plot will be created to display the animation, otherwise the animation will take place in the selected plot.

The Scaling option: radio buttons control how a spectrum is scaled when it is displayed.

• Auto selecting this option (the default) makes each spectrum, and any other spectra already displayed in the target plot, fit themselves to the width and height of the plot display area.
• Fix selecting this option makes each spectrum respect the data limits already applied to the plot. So to make effective use of this option you need to display into an existing plot and have set the data limits (using the plot configuration window). It’s expected that this will be most useful when comparing a list of spectra against a single pre-plotted spectrum, or when creating an animation sequence for a movie (so you need to also use the Capture controls).
• Free selecting this option makes the spectrum add itself without constraints to the plot. This is essentially the same as just adding a spectrum to a plot using the browser window controls (i.e. the data limits of the plot are produced by combinating the data limits of any pre-plotted spectra and the one added, these are all scaled to fit).

The Current spectrum label just displays the name of the spectrum currently being added to the target plot. This information is repeated in the plot itself as the spectrum becomes the current one in the plot and is named in the Displaying: label.

The Start, Pause and Stop buttons do what is expected.

Capture controls

The capture controls are for creating a series of JPEG or PNG images of the plot as it displays each spectrum. To enable (after getting the required effect using the Animation controls) just click on the Start capture: check box. The output file names will start with what name you type into the Basename for graphics files: entry and have an integer number appended, plus the file type .jpg or .png. So a default sequence would be SPLAT0.jpg, SPLAT1.jpg, SPLAT2.jpg,... You’ll then need to find some software to convert these into a movie. The ImageMagick convert command (when suitably configured) will convert these files into an MPEG or animated GIF. The image below was created with the command (note that the images were also scaled – view the html documentation or the pdf documentation in a viewer that supports animation such as Adobe Reader to see the animation.):

% convert -delay 50 -loop 0 SPLAT0.jpg SPLAT1.jpg SPLAT2.jpg \
splatmovie.gif

Accelerator keys

• Control-w Close the window.
• F1 Display help on SPLAT-VO.
• Shift-F1 Display help on window.