public void setQuality(int quality) {
        if (quality < 1) quality = 1;
        sample = quality;
    }
Sets quality of color quantization (conversion of images
to the maximum 256 colors allowed by the GIF specification).
Lower values (minimum = 1) produce better colors, but slow
processing significantly.  10 is the default, and produces
good color mapping at reasonable speeds.  Values greater
than 20 do not yield significant improvements in speed.

@param quality int greater than 0.
@return
plugins/base-plugin/src/main/java/com/github/hui/quick/plugin/base/gif/GifEncoder.java