在Golang中将多部分文件转换为图像对象

I'm attempting to upload an image, resize it and then upload it to Amazon S3 in go, however I'm struggling to figure out how to convert the image from multipart.File to image.Image

package controllers

import (
    "github.com/gin-gonic/gin"
    "github.com/mitchellh/goamz/aws"
    "github.com/mitchellh/goamz/s3"
    "github.com/nfnt/resize"
    _ "image/jpeg"
    "log"
    "os"
    "strconv"
)

type ResizeController struct {
}

func NewResizeController() *ResizeController {
    return &ResizeController{}
}

func (rc ResizeController) Resize(c *gin.Context) {

    auth, err := aws.EnvAuth()

    if err != nil {
        log.Fatal(err)
    }

    client := s3.New(auth, aws.EUWest)
    bucket := client.Bucket(os.Getenv("AWS_BUCKET_NAME"))

    file, header, err := c.Request.FormFile("file")
    filename := header.Filename

    height := c.Query("height")
    width := c.Query("width")

    h64, err := strconv.ParseUint(height, 10, 32)
    w64, err := strconv.ParseUint(width, 10, 32)
    h := uint(h64)
    w := uint(w64)

    m := resize.Resize(w, h, file, resize.Lanczos3)

    err = bucket.Put("/content/"+filename, m, "content-type", s3.Private)

    c.JSON(200, gin.H{"filename": header.Filename})
}

I'm getting the error controllers/resize_controller.go:43: cannot use file (type multipart.File) as type image.Image in argument to resize.Resize:

Figured it out, I just needed to use

image, err := jpeg.Decode(file)