[magick-developers] Problems with convert

[Glenn Randers-Pehrson]

At 06:49 PM 11/2/2007 +0000, you wrote:
>On 11/2/07, Michael Lehn <michael.lehn at uni-ulm.de> wrote:
>> I want to visualize results of a numerical simulation.  This produces
>> for example 6000 images (typically I need much more):
>>
>>         data/particle_0001.gif
>>         data/particle_0002.gif
>>         data/particle_0003.gif
>>         data/particle_0004.gif
>>         data/particle_0005.gif
>>         data/particle_0006.gif
>>         data/particle_0007.gif
>>         ...
>>         data/particle_6000.gif
>>
>> My naive idea was to create an animated gif
>
>I would suggest another image format. How about generating a movie
>file, such as mpeg? You'll save a *huge* amount of space. Plus, if you
>encode correctly, you'll be able to seek backwards and forwards in
>your file.

Mpeg might not be too good for images from a numerical simulation.  If
it contains lines and sharp boundaries, the lossy compression of Mpeg
will not look good and will not compress well.

I would use MNG, and make a large tiled image, like a microfiche
film, containing all 6000
images in one PNG file, with MOVE and CLIP instructions to display
each tile in sequence.

convert -append <images 0000-0099> row00.ppm
convert -append <images 0100-0199> row01.ppm
...
convert -append <images 5900-5999> row59.ppm
convert +append row*.ppm all.png
rm row*.png

Then embed all.png in a MNG, supposing each tile is 200x200:
MHDR 200 200 ... ticks_per_second
DEFI 01 ... 19800 -200
all.png
LOOP 01 60
MOVE 01 01 -20000 200
LOOP 02 100
MOVE 01 01 200 0
SHOW 01 01
ENDL 02
ENDL 01
MEND

With the proposed AniPNG format, it would be a little simpler,
something like:

MHDR 200 200 ... ticks_per_second
DEFI 01 ... 19800 -200
all.png
LOOP 01 60
PLAY 01 -20000 200 ... ticks
LOOP 02 99
PLAY 01 200 0 ... ticks
ENDL 02
ENDL 01

Glenn