Re: Animations with image size matching output resolution

[Daniel J S. <dan...@ie...>]

I've tried a ton of software now.  (Couldn't get xanim to work.)  Believe it or not gthumb and the animated GIF combination seem the most useful.

Here's a good summary of software

http://www.gfdl.noaa.gov/products/vis/animation/

Their comment is mplayer is good, GIF not good.


My thoughts:

mplayer/mencoder
----------------
Awesome program, however it is a bit more than I particularly need.  (This is the first time I've been able to view the movie on my Peter Gabriel O.V.O. Millenium Show CD... yeah, only took five years.)  mencoder works well for assembling images of various formats.  However, drawbacks

o Can't step through frame by frame (why I don't know)
o I can't seem to figure out how to get unsmoothed images,
  especially in full screen mode.  Either the image format loses
  resolution or the program automatically does image smoothing.
  It doesn't matter the output format I choose, e.g. AVI, PNG.
  There are filters and all kinds of options; too much given
  the goal is no image processing after what I've already done.
o The GUI or "skin" adds nothing really--waste of time.

Recommended as a general tool, but could be better.


animate
-------
Works with GIF animation and separately stored PNG files.  Can step through images.  Drawbacks:

o There is no nice full screen mode.  Have to specify a size
  at the command line.  Even then, the image isn't centered, but
  over to the left edge.
o When expanded, there is smoothing of the image and appears
  to be no way of controlling it, which is odd because ImageMagick
  looks very good when expanded.

Not recommended.


Helix/Real Player
-----------------
Surprisingly this works with animated GIF files.  Drawbacks

o Ever so slight loss of resolution when placed in full
  screen mode.
o Doesn't step through so well.

Not recommended, close though.


gthumb
------
Works with animated GIF, grayscale or color.  No image smoothing in full screen mode (must specify low-quality image in preferences).  Can stop animation, and can step through.  Drawbacks:

o There is no hot key for stepping through the images.  Oh well.

Recommended.


gifsicle
--------
Not for viewing, but it is a very flexible program for working with GIF images.  Too bad mencoder doesn't work so seamlessly.


So, my thought on this is that GIF isn't as undesirable as one might guess.

I see there is a format called MNG; like with PNG there is a libmng library.  (Something called JNG too.)  Maybe a gnuplot MNG terminal is the way to go with this sort of thing.

Dan



Ethan A Merritt wrote:
> On Thursday 29 December 2005 12:30 pm, you wrote:
> 
>>No doubt.  However, cropping of images is such a useful thing that it
>>could have it's special case in the gnuplot core.  
> 
> 
> It cannot be implemented in the core, because it is a terminal-specific
> operation.  E.g., how on earth would the core code know anything about
> a particular pixel in an output png image?  Even more impossible is to
> know about the "pixels" in an output PostScript file whose font
> characteristics will only be determined by the eventual print device.
> 
> 
>>Well, JPEG is out.  
> 
> 
> Are you talking about mencoder here?
> 
> 
>>The help has nothing about lossless images, but JPEG 
>>has interpolation and is not acceptable in this application.
> 
> 
> JPEG supports a loss-less mode.  But yes, normally if you want
> loss-less images you would pick a different format.
> 
> Animation normally involves interpolation between frames, and saves
> space by sending full "index" frames every Nth frame but intervening
> update frames with only incremental or interpolated contents.
> The ratio of full to partial/interpolated frames can be set at the
> time you encode the animation.
> Sounds like you want index frames only. That is definitely possible.
> 
> 
>>Yeah.  What is the animated GIF for, really, in terms of gnuplot?  
> 
> 
> A/B comparisons?
> Sequential evolution of a plot feature?
> Build-up of a complicated plot from component features?
> 
> 
>>I mean, assembling a movie is a far more meaningful thing in the
>>scientific community than an animated graphic for a web page.
> 
> 
> A whole lot more people can easily view an embedded gif on a web
> page than will take the time to install some fancy movie-player
> just so they can afterwards download and look at your plot.
> 
> 
>>Alright, let me look at generating movies with ImageMagick...
> 
> 
> Wrong tool.
> You really do want mencoder.  Believe me.
> But you may have to build it from source to get a full range of
> supported formats.
> 


-- 

Dan Sebald
phone: 608 256 7718
email: daniel DOT sebald AT ieee DOT org
URL: http://webpages DOT charter DOT net/dsebald/