Which resize filter is used when resizing a gif image?

[carol_sun]

MagickStudio can resize a gif image keeping it movie. It loop though the current image sequence resizing all images.
I want to know that which resize filter is used by MagickStudio when doing this?

I used point filter to resize each frame, it didn't work well all of the time. Did i lose some step?

Code: Select all

        list<Image> imageList; 
        readImages( &imageList, "dog.gif"); 
        Magick::Geometry gm(100, 100);    
        for_each ( imageList.begin(), imageList.end(), sampleImage(gm));         // resize all images.
        writeImages( imageList.begin(), imageList.end(), "output.gif");             

[magick]

You can always review the source to MagickStudio at ftp://ftp.imagemagick.org/pub/ImageMagick/perl. We suspect it uses the default resize filters Mitchell and Lanzos.