decode webcam

decode.go

package main

import (
	"fmt"
	"image/jpeg"
	"io"
	"log"
	"mime/multipart"
	"os/exec"
)

func main() {
	cmd := exec.Command("ffmpeg", "-f", "avfoundation", "-pix_fmt", "0rgb", "-r", "30", "-i", "FaceTime", "-f", "mpjpeg", "-")
	out, err := cmd.StdoutPipe()
	if err != nil {
		log.Fatal(err)
	}
	if err := cmd.Start(); err != nil {
		log.Fatal(err)
	}
	mr := multipart.NewReader(out, "ffserver")
	for {
		p, err := mr.NextPart()
		if err == io.EOF {
			return
		}
		if err != nil {
			log.Fatal(err)
		}
		m, err := jpeg.Decode(p)
		if err != nil {
			log.Fatal(err)
		}
		fmt.Println("frame bounds", m.Bounds())
	}
}