Go making gif animations

Today, I read the "Go Language Bible" of golang Chinese community translation, and in Chapter 1.4, I talked about animating gif with go, which is very interesting to share with everyone.

Package Main

Import (

"Image"

"Image/color"

"Image/gif"

"IO"

"Math"

"Math/rand"

"OS"

)

var palette = []color. Color{color. White, color. Black}//Palette

Const (

Whiteindex = 0

Blackindex = 1

)

Func Main () {

Lissajous (OS. Stdout)

}

Func lissajous (out IO. Writer) {

Const (

Cycles  = 5

Res     = 0.001

Size    = 100

Nframes = 64

Delay   = 8

)

Freq: = Rand. Float64 () * 3.0

ANIM: = gif. Gif{loopcount:nframes}

Phase: = 0.0

For I: = 0; i < nframes; i++ {

Rect: = image. Rect (0, 0, 2*size+1, 2*size+1)

IMG: = image. newpaletted (rect, palette)

For t: = 0.0; T < Cycles*2*math. Pi; T + = res {

x: = Math. Sin (t)

Y: = Math. Sin (t*freq + phase)

Img. Setcolorindex (Size+int (x*size+0.5), Size+int (y*size+0.5), Blackindex)

}

Phase + = 0.1

Anim. Delay = Append (anim. Delay, delay)

Anim. Image = Append (anim. Image, IMG)

}

Gif. Encodeall (out, &anim)

}


$./gif >out.gif

Go making gif animations