timeimage.go

package main

import (
	"fmt"
	"image"
	"image/draw"
	"io/ioutil"
	"math/rand"
	"net/http"
	"path"
	"time"

	"github.com/disintegration/imaging"
	"github.com/golang/freetype"
)

func main() {
	urls := []string{
		"http://pic.prepics-cdn.com/xxx888xxx/40714761.jpeg",
		"https://images-na.ssl-images-amazon.com/images/I/81h5pQdGJHL.jpg",
		"http://digzoom.com/wp-content/uploads/2016/01/nishinonanase1.jpg",
	}

	rand.Seed(time.Now().UnixNano())
	u := urls[rand.Intn(len(urls)-1)]

	res, err := http.Get(u)
	if err != nil {
		fmt.Println(err)
		return
	}

	defer res.Body.Close()

	img, _, err := image.Decode(res.Body)
	if err != nil {
		fmt.Println(err)
		return
	}

	_, name := path.Split(u)

	fb, err := ioutil.ReadFile("font.ttf")
	if err != nil {
		fmt.Println(err)
		return
	}

	f, err := freetype.ParseFont(fb)
	if err != nil {
		fmt.Println(err)
		return
	}

	rgba := image.NewRGBA(img.Bounds())
	draw.Draw(rgba, rgba.Bounds(), img, image.ZP, draw.Src)
	c := freetype.NewContext()
	c.SetDPI(72)
	c.SetFont(f)
	c.SetFontSize(200)
	c.SetClip(rgba.Bounds())
	c.SetDst(rgba)
	c.SetSrc(image.Black)

	location, err := time.LoadLocation("Asia/Tokyo")
	if err != nil {
		fmt.Println(err)
		return
	}

	now := time.Now().In(location)
	pt := freetype.Pt(rgba.Bounds().Size().X/2-100, rgba.Bounds().Size().Y-50)
	if _, err := c.DrawString(fmt.Sprintf("%02d:%02d", now.Hour(), now.Minute()), pt); err != nil {
		fmt.Println(err)
	}
	imaging.Save(rgba, name)
}