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Problems resizing cinemagraphs (animated GIFs)

I have resizing problems. If you don’t know, this is a gif where only a part of the image is animated, compared to a regular gif where the whole image is animated. Here is an example node.js:

// ![http://i.imgur.com/Qb1m0.gif][1]

var gm = require('gm')

var file = 'Qb1m0.gif',
    frags = file.split('.')

gm(file)
  //.noProfile()
  //.quality(80)
  .resize(200, 200)
  .write(frags[0] + '_200.' + frags[1], function(err) {
    if (err) console.error(err)
  })

// Result:
// ![http://i.imgur.com/eFqak.gif][2]

And the equivalent cmd line code:

gm convert Qb1m0.gif -resize 200x200 cinema_200.gif

Know what is going on?

Original animated GIF:

Original

Modified animated GIF:

Resized

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1 answer

I know ImageMagick is better than GraphicsMagick. For ImageMagick, the following statements apply:

  • It is not possible to directly resize animated GIF files using a simple command line (for example, the one you gave) if the GIF contains transparency.

  • , GIF .

, GraphicsMagick.

GIF identify, , :

identify Qb1m0.gif
 Qb1m0.gif[1]  GIF 720x416 720x416+0+0    8-bit PseudoClass 256c 920KB 0.000u 0:00.009
 Qb1m0.gif[1]  GIF 471x122 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.009
 Qb1m0.gif[2]  GIF 471x121 720x416+160+76 8-bit PseudoClass 256c 920KB 0.000u 0:00.009
 Qb1m0.gif[3]  GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.009
 Qb1m0.gif[4]  GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.009
 Qb1m0.gif[5]  GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.009
 Qb1m0.gif[6]  GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.009
 Qb1m0.gif[7]  GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.009
 Qb1m0.gif[8]  GIF 471x122 720x416+160+76 8-bit PseudoClass 256c 920KB 0.000u 0:00.009
 Qb1m0.gif[9]  GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.009
 Qb1m0.gif[10] GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.000
 Qb1m0.gif[11] GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.000
 Qb1m0.gif[12] GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.000
 Qb1m0.gif[13] GIF 471x122 720x416+160+76 8-bit PseudoClass 256c 920KB 0.000u 0:00.000
 Qb1m0.gif[14] GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.000
 Qb1m0.gif[15] GIF 471x123 720x416+160+75 8-bit PseudoClass 256c 920KB 0.000u 0:00.000

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convert                        \
  http://i.imgur.com/Qb1m0.gif \
 -coalesce                     \
 -resize 200x200               \
  cinema_200.gif

:

  Result

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