Editing Vtk/MovieMaking (section)

===Animated GIF===
====Using ''convert''====
* Via the Mac's terminal window, change directories into the folder that contains the image sequence.  
* As necessary, rename image files in order to define the desired image sequence:
** The "convert" program (see next instruction step) expects the file names to be in a consecutively numbered sequence;
** Assuming PNG-formatted image types, we recommend using the numbering sequence:  a01.png, a02.png, a03.png, etc.
** If you want a smooth back-and-forth animation loop and you are starting with 9 images (numbered a01 thru a09), make additional copies of images such that the entire animation is: 1-2-3-4-5-6-7-8-9-8-7-6-5-4-3-2.  But the last seven images should be ''named'' a10.png, a11.png, a12.png &hellip; a16.png.
* Type one of the following two commands (2nd one preferred!):
<pre>convert -set delay 3 -colorspace GRAY -colors 16 -dispose 1 -loop 0 -scale 50% *.png Output.gif</pre>
<pre>convert -set delay 10 -colors 1024 -dispose 1 -loop 0 -scale 100% *.png Output.gif</pre>

* Related information:
** I initially extracted the first of these recommended "convert" instructions from [http://pages.uoregon.edu/noeckel/MakeMovie.html Jens N&ouml;ckel's web site].
** My Mac contains a manual on this "convert" instruction (man convert); it points out that, "The <b>convert</b> program is a member of the ImageMagick(1) suite of tools."
** The Mac's "convert" manual also refers to a [http://www.imagemagick.org/script/convert.php convert website].

* Finally, rename the "Output.gif" file to something that better identifies the content; upload the renamed "Output.gif" file to the VisTrails wiki site; and insert it into the desired wiki page just as you would insert a single image.

====Using Keynote====
On 30 May 2021, I acquired a new iMac to replace the (desktop) Mac Pro that I have relied on since 2010.  This new system's "Big Sur" (v11.4) macOS encounters an error when I try to execute ''convert''; I think this is because convert's binary executable is incompatible with my new iMac's CPU hardware.  [https://support.apple.com/guide/keynote/create-an-animated-gif-tan30ff1f63c/mac Online discussions] appear to recommend that animated gifs be constructed using Apple's "Keynote" (''aka'' Powerpoint) utility.
* Create a new, blank Keynote file;
* Paste (drag-and-drop) the first gif image onto the first slide of this new file;
* Add a second, blank slide to the Keynote file, then paste the 2nd gif image onto this slide;
* etc.; [make sure each image sits in precisely the same position on each slide]
* Under Keynote's "File" dropdown menu, 
** choose "Export to ... Animated gif ..."
** identify the range of slides (e.g., 2 thru 28) that are to be incorporated into the animation, and the desired frame rate;
** click "Next", etc.