grokify/mogo

package imageutil

import (
    "image"
    "image/gif"
)

func BuildGifAnimationSimpleRead(src *gif.GIF, delay int, names []string, f ToPalettedFunc, consistentSize bool) (*gif.GIF, error) {
    imgs, err := ReadImages(names)
    if err != nil {
        return nil, err
    }
    if consistentSize {
        imgs2 := Images(imgs)
        imgs2.ConsistentSize(ScalerBest(), AlignCenter)
        imgs = []image.Image(imgs2)
    }
    return BuildGifAnimationSimple(src, delay, imgs, f), nil
}

// BuildGifAnimationSimple assembles a set of images in an animated GIF file.
// Set `delay` to `0`.
func BuildGifAnimationSimple(src *gif.GIF, delay int, imgs []image.Image, f ToPalettedFunc) *gif.GIF {
    if src == nil {
        src = &gif.GIF{}
    }
    for _, img := range imgs {
        pimg := imageToPalettedFuncWrap(img, f)
        src.Image = append(src.Image, pimg)
        src.Delay = append(src.Delay, delay)
    }
    return src
}

func imageToPalettedFuncWrap(src image.Image, f ToPalettedFunc) *image.Paletted {
    if v, ok := src.(*image.Paletted); ok {
        return v
    }
    if f != nil {
        return f(src)
    }
    return ImageToPalettedPlan9(src)
}