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Over-inflated 100x MNG creation with convert 6.0.6

Posted: 2006-03-14T01:46:47-07:00
by mtodorov3_69
Hi, all!

I have tried the simple sequence like this to create MNG logo with ImageMagick:

% convert -d 5 model-*.png ~/public_html/grf-logo/grf-logo.mng

The result is convincing, and can be seen on:

BUT!!!!!! It is 3 MB huge for an image 640x480. It would be normal if the image isn't
mostly static, with only a small rotor rotating (see image).


Animated GIF of the same image sequence is 35K long!! See for yourself:

I would keep the GIF logo then , because 3 MB for a logo is not acceptable,
but alas the colors in animated GIF are terrible, and there seem to be no remedies.

Was there som eenhancement in MNG creation since convert 6.0.6 and do you by chance know of some MNG compression or optimizer tool?

I think having 100x big image is definitely a bug, or no attempt is made to recognize patterns or parts of image(s) that repeat or stay same in sequence.

Thank you, otherwise the program is great!


Posted: 2006-03-14T21:09:39-07:00
by anthony
The whole image should not be needed for a MNP animation, just as the whole image is not needed for a GIF animation.

convert grf-logo.mng -deconstruct -set delay 20 grf-logo_2.mng

Produces a much smaller image, though still larger than GIF. The size may be reduced further by playing with the -quality settings.

NOTE: for PNG and PNG quality is not just a number from 0 to 99, it is two seperate digits with two separte meanings.

My movie player even plays it fine too.

NOTE: This is basic frame optimization. I know the PNG and MNG both allow a image offset so I know they handle sub-frame overlays. However I do not know if MNG understands GIF dispose methods or anything else about that animation format. As such I do not recoment you use the new GIF "-layer optimize" methods with MNG animations at this time.

If anyone out there can enlighten me, I would be happy to hear from you.

For more info in Animations (that I so far have developed for IM use) see ... im_basics/